Interscience Conference on Antimicrobial Agents & Chemotherapy (ICAAC)

CHICAGO – Plazomicin, an investigational aminoglycoside previously know as ACHN-490, is a promising new agent for treating gram-negative infections, according to George G. Zhanel, Ph.D.

"There’s something exciting about working with an agent that’s a modification of something you know a lot about, because you think you’ll be able to predict some of the problems," Dr. Zhanel said at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).

"But let’s be clear: We have no human efficacy and safety data. We need the data to see that this agent works for aminoglycoside-resistant infections, and we need to see that data on nephrotoxicity and ototoxicity. We need to be monitoring the spread of rRNA methylases."

Aminoglycosides have well-described pharmacokinetics and proven efficacy alone and in combination with other agents, "but you are not using them very much because there is worldwide resistance, primarily due to aminoglycoside-modifying enzymes but also well-described nephrotoxicity and ototoxicity," said Dr. Zhanel of the department of medical microbiology and infectious diseases at the University of Manitoba, Winnipeg. "However, clearly there is a need for these agents and other new antimicrobials."

In the past decade, many researchers have been working to further develop aminoglycosides, including arbekacin analogues, gentamicin analogues, isepamicin analogues, streptomycin analogues, and plazomicin, which is an analogue of sisomicin and is manufactured by San Francisco–based Achaogen. A recent study from the United Kingdom found that plazomicin MIC₉₀ (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) was less than or equal to 2 mg/L against carbapenem-resistant Enterobacteriaceae (J. Antimicrob. Chemother. 2011;66:48-53). The researchers also found that plazomicin was 16 times more active than amikacin and 8 times more active than gentamicin. "Importantly, none of the aminoglycosides, including plazomicin, were active against NDM-carrying strains with both metallo-beta-lactamase and methyltransferase," said Dr. Zhanel, who is director of the Canadian Antimicrobial Resistance Alliance.

Plazomicin demonstrates synergy with other agents, he continued. In vitro time-kill studies of methicillin-resistant Staphylococcus aureus demonstrated 91.5% efficacy for plazomicin plus daptomycin, compared with 36.2% for plazomicin plus ceftobiprole and 12.8% for plazomicin plus linezolid (Antimicrob. Agents Chemother. 2010;54:2258-61).

In vitro time-kill studies of Pseudomonas aeruginosa demonstrated 92% synergy for plazomicin plus piperacillin/tazobactam, compared with 80% for plazomicin plus cefepime and 80% for plazomicin plus doripenem (Antimicrob. Agents Chemother. 2011;55:2463-5).

In a poster presented at the 2010 ICAAC meeting, researchers presented findings from a phase I pharmacokinetics and safety study of plazomicin administered to eight subjects at a dose of 15 mg/kg IV once daily for 5 days. The study, sponsored by Achaogen, found that the mean C_max was 113 mcg/mL, the mean AUC (0-24 hr) was 239 mcg/mL per hour, the mean C_min was 0.4 mcg/mL, and the mean half-life was 3 hours. There was no evidence of nephrotoxicity or ototoxicity, and all adverse events were reported as mild to moderate.

Dr. Zhanel said that a multicenter, randomized phase II trial of plazomicin for complicated urinary tract infections and acute pyelonephritis is underway. The comparator drug will be levofloxacin.

"Clearly, plazomicin is a promising new agent," Dr. Zhanel said at the meeting, which was sponsored by the American Society for Microbiology. "If future studies show that it is effective against aminoglycoside-susceptible and -resistant infections, and/or if the agent shows nephrotoxicity and/or ototoxicity less than the current aminoglycosides, you may want to use this compound in select cases as your aminoglycoside of choice."

Dr. Zhanel disclosed that he has received research funding from the National Institutes of Health and numerous other sources, including Achaogen and other pharmaceutical companies.

CHICAGO – Plazomicin, an investigational aminoglycoside previously know as ACHN-490, is a promising new agent for treating gram-negative infections, according to George G. Zhanel, Ph.D.

"There’s something exciting about working with an agent that’s a modification of something you know a lot about, because you think you’ll be able to predict some of the problems," Dr. Zhanel said at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).

"But let’s be clear: We have no human efficacy and safety data. We need the data to see that this agent works for aminoglycoside-resistant infections, and we need to see that data on nephrotoxicity and ototoxicity. We need to be monitoring the spread of rRNA methylases."

Aminoglycosides have well-described pharmacokinetics and proven efficacy alone and in combination with other agents, "but you are not using them very much because there is worldwide resistance, primarily due to aminoglycoside-modifying enzymes but also well-described nephrotoxicity and ototoxicity," said Dr. Zhanel of the department of medical microbiology and infectious diseases at the University of Manitoba, Winnipeg. "However, clearly there is a need for these agents and other new antimicrobials."

In the past decade, many researchers have been working to further develop aminoglycosides, including arbekacin analogues, gentamicin analogues, isepamicin analogues, streptomycin analogues, and plazomicin, which is an analogue of sisomicin and is manufactured by San Francisco–based Achaogen. A recent study from the United Kingdom found that plazomicin MIC₉₀ (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) was less than or equal to 2 mg/L against carbapenem-resistant Enterobacteriaceae (J. Antimicrob. Chemother. 2011;66:48-53). The researchers also found that plazomicin was 16 times more active than amikacin and 8 times more active than gentamicin. "Importantly, none of the aminoglycosides, including plazomicin, were active against NDM-carrying strains with both metallo-beta-lactamase and methyltransferase," said Dr. Zhanel, who is director of the Canadian Antimicrobial Resistance Alliance.

Plazomicin demonstrates synergy with other agents, he continued. In vitro time-kill studies of methicillin-resistant Staphylococcus aureus demonstrated 91.5% efficacy for plazomicin plus daptomycin, compared with 36.2% for plazomicin plus ceftobiprole and 12.8% for plazomicin plus linezolid (Antimicrob. Agents Chemother. 2010;54:2258-61).

In vitro time-kill studies of Pseudomonas aeruginosa demonstrated 92% synergy for plazomicin plus piperacillin/tazobactam, compared with 80% for plazomicin plus cefepime and 80% for plazomicin plus doripenem (Antimicrob. Agents Chemother. 2011;55:2463-5).

In a poster presented at the 2010 ICAAC meeting, researchers presented findings from a phase I pharmacokinetics and safety study of plazomicin administered to eight subjects at a dose of 15 mg/kg IV once daily for 5 days. The study, sponsored by Achaogen, found that the mean C_max was 113 mcg/mL, the mean AUC (0-24 hr) was 239 mcg/mL per hour, the mean C_min was 0.4 mcg/mL, and the mean half-life was 3 hours. There was no evidence of nephrotoxicity or ototoxicity, and all adverse events were reported as mild to moderate.

Dr. Zhanel said that a multicenter, randomized phase II trial of plazomicin for complicated urinary tract infections and acute pyelonephritis is underway. The comparator drug will be levofloxacin.

"Clearly, plazomicin is a promising new agent," Dr. Zhanel said at the meeting, which was sponsored by the American Society for Microbiology. "If future studies show that it is effective against aminoglycoside-susceptible and -resistant infections, and/or if the agent shows nephrotoxicity and/or ototoxicity less than the current aminoglycosides, you may want to use this compound in select cases as your aminoglycoside of choice."

Dr. Zhanel disclosed that he has received research funding from the National Institutes of Health and numerous other sources, including Achaogen and other pharmaceutical companies.

CHICAGO – Plazomicin, an investigational aminoglycoside previously know as ACHN-490, is a promising new agent for treating gram-negative infections, according to George G. Zhanel, Ph.D.

"There’s something exciting about working with an agent that’s a modification of something you know a lot about, because you think you’ll be able to predict some of the problems," Dr. Zhanel said at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).

"But let’s be clear: We have no human efficacy and safety data. We need the data to see that this agent works for aminoglycoside-resistant infections, and we need to see that data on nephrotoxicity and ototoxicity. We need to be monitoring the spread of rRNA methylases."

Aminoglycosides have well-described pharmacokinetics and proven efficacy alone and in combination with other agents, "but you are not using them very much because there is worldwide resistance, primarily due to aminoglycoside-modifying enzymes but also well-described nephrotoxicity and ototoxicity," said Dr. Zhanel of the department of medical microbiology and infectious diseases at the University of Manitoba, Winnipeg. "However, clearly there is a need for these agents and other new antimicrobials."

In the past decade, many researchers have been working to further develop aminoglycosides, including arbekacin analogues, gentamicin analogues, isepamicin analogues, streptomycin analogues, and plazomicin, which is an analogue of sisomicin and is manufactured by San Francisco–based Achaogen. A recent study from the United Kingdom found that plazomicin MIC₉₀ (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) was less than or equal to 2 mg/L against carbapenem-resistant Enterobacteriaceae (J. Antimicrob. Chemother. 2011;66:48-53). The researchers also found that plazomicin was 16 times more active than amikacin and 8 times more active than gentamicin. "Importantly, none of the aminoglycosides, including plazomicin, were active against NDM-carrying strains with both metallo-beta-lactamase and methyltransferase," said Dr. Zhanel, who is director of the Canadian Antimicrobial Resistance Alliance.

Plazomicin demonstrates synergy with other agents, he continued. In vitro time-kill studies of methicillin-resistant Staphylococcus aureus demonstrated 91.5% efficacy for plazomicin plus daptomycin, compared with 36.2% for plazomicin plus ceftobiprole and 12.8% for plazomicin plus linezolid (Antimicrob. Agents Chemother. 2010;54:2258-61).

In vitro time-kill studies of Pseudomonas aeruginosa demonstrated 92% synergy for plazomicin plus piperacillin/tazobactam, compared with 80% for plazomicin plus cefepime and 80% for plazomicin plus doripenem (Antimicrob. Agents Chemother. 2011;55:2463-5).

In a poster presented at the 2010 ICAAC meeting, researchers presented findings from a phase I pharmacokinetics and safety study of plazomicin administered to eight subjects at a dose of 15 mg/kg IV once daily for 5 days. The study, sponsored by Achaogen, found that the mean C_max was 113 mcg/mL, the mean AUC (0-24 hr) was 239 mcg/mL per hour, the mean C_min was 0.4 mcg/mL, and the mean half-life was 3 hours. There was no evidence of nephrotoxicity or ototoxicity, and all adverse events were reported as mild to moderate.

Dr. Zhanel said that a multicenter, randomized phase II trial of plazomicin for complicated urinary tract infections and acute pyelonephritis is underway. The comparator drug will be levofloxacin.

"Clearly, plazomicin is a promising new agent," Dr. Zhanel said at the meeting, which was sponsored by the American Society for Microbiology. "If future studies show that it is effective against aminoglycoside-susceptible and -resistant infections, and/or if the agent shows nephrotoxicity and/or ototoxicity less than the current aminoglycosides, you may want to use this compound in select cases as your aminoglycoside of choice."

Dr. Zhanel disclosed that he has received research funding from the National Institutes of Health and numerous other sources, including Achaogen and other pharmaceutical companies.

CHICAGO – Compressing the usual 3-day course of intravenous azithromycin into a single high dose appears to be a safe, efficacious alternative for treating community-acquired pneumonia in adult outpatients.

In an open-label, randomized trial, investigators in Austria compared the same total dose of azithromycin either split over 3 days or given as a single infusion among 72 outpatients with community-acquired pneumonia (CAP).

Trial results, reported at the annual Interscience conference on Antimicrobial Agents and Chemotherapy, showed that the two regimens had similar efficacy and adverse effect profiles. In both groups, nearly 90% of patients were cured.

Photo: ©WILLSIE/iStockphoto.com

The single-dose strategy ensures high levels of the drug independent of patient compliance, according to presenting author Dr. Rainer Gattringer of the Elisabethinen Hospital and Analyse BioLab, both in Linz, Austria. Additionally, it may reduce treatment costs.

"I think maybe physicians are a little bit afraid because it’s not written in the description of the drug that you can use it at 1.5 g as a single dose," he proposed in an interview. "They say, I have no experience with it, and they don’t know about side effects and so on."

But the drug appeared safe and well tolerated with the protocol used in the trial: administration in a liter of infusion solution given over an extended period of 4 hours. "That [protocol] is I think the main thing," Dr. Gattringer said. "So don’t be afraid, try it."

The patients studied were 45 years old, on average, and 65% were men, according to data reported in a poster session. They were fairly healthy, Dr. Gattringer noted; the CRB-65 (confusion, respiratory rate, blood pressure, and age 65 years or older) score was 0, 1, and 2 in 33.3%, 51.4%, and 15.3%, respectively. Overall, 18% had previously received oral antibiotic therapy.

The most common pathogens identified were Streptococcus pneumoniae (22.2% of patients), Mycoplasma pneumoniae (6.9%), Legionella pneumophila (6.9%), Coxiella burnetii (1.4%), and Cytomegalovirus (1.4%). No pathogen was identified in 59.7% of cases.

The patients received either a single IV dose of 1.5 g azithromycin (diluted in 1 L of lactated Ringer solution and given as a 4-hour infusion) or the conventional dose schedule of 500 mg azithromycin IV once daily for 3 days.

Azithromycin is especially useful in patients who have an allergy to beta-lactam antibiotics, and the intravenous formulation is attractive given that oral macrolides, including azithromycin, have low bioavailability, Dr. Gattringer noted at the conference, which was sponsored by the American Society for Microbiology.

The rate of clinical cure – defined as resolution of fever within 72 hours; disappearance of other clinical and laboratory signs of inflammation, including achievement of C-reactive protein level of less than 1 mg/dL; and no need for additional antimicrobial therapy at 10 days – was statistically indistinguishable between the single-dose group and the conventional-regimen group (87.2% vs. 87.9%).

With the single-dose strategy, "you can send the patient home and you can achieve the right level of the drug in the patient," he concluded.

Dr. Gattringer reported having no conflicts of interest related to the trial. The trial was supported by a grant from Pfizer Research, manufacturer of Zithromax (azithromycin).

CHICAGO – Compressing the usual 3-day course of intravenous azithromycin into a single high dose appears to be a safe, efficacious alternative for treating community-acquired pneumonia in adult outpatients.

In an open-label, randomized trial, investigators in Austria compared the same total dose of azithromycin either split over 3 days or given as a single infusion among 72 outpatients with community-acquired pneumonia (CAP).

Trial results, reported at the annual Interscience conference on Antimicrobial Agents and Chemotherapy, showed that the two regimens had similar efficacy and adverse effect profiles. In both groups, nearly 90% of patients were cured.

Photo: ©WILLSIE/iStockphoto.com

The single-dose strategy ensures high levels of the drug independent of patient compliance, according to presenting author Dr. Rainer Gattringer of the Elisabethinen Hospital and Analyse BioLab, both in Linz, Austria. Additionally, it may reduce treatment costs.

"I think maybe physicians are a little bit afraid because it’s not written in the description of the drug that you can use it at 1.5 g as a single dose," he proposed in an interview. "They say, I have no experience with it, and they don’t know about side effects and so on."

But the drug appeared safe and well tolerated with the protocol used in the trial: administration in a liter of infusion solution given over an extended period of 4 hours. "That [protocol] is I think the main thing," Dr. Gattringer said. "So don’t be afraid, try it."

The patients studied were 45 years old, on average, and 65% were men, according to data reported in a poster session. They were fairly healthy, Dr. Gattringer noted; the CRB-65 (confusion, respiratory rate, blood pressure, and age 65 years or older) score was 0, 1, and 2 in 33.3%, 51.4%, and 15.3%, respectively. Overall, 18% had previously received oral antibiotic therapy.

The most common pathogens identified were Streptococcus pneumoniae (22.2% of patients), Mycoplasma pneumoniae (6.9%), Legionella pneumophila (6.9%), Coxiella burnetii (1.4%), and Cytomegalovirus (1.4%). No pathogen was identified in 59.7% of cases.

The patients received either a single IV dose of 1.5 g azithromycin (diluted in 1 L of lactated Ringer solution and given as a 4-hour infusion) or the conventional dose schedule of 500 mg azithromycin IV once daily for 3 days.

Azithromycin is especially useful in patients who have an allergy to beta-lactam antibiotics, and the intravenous formulation is attractive given that oral macrolides, including azithromycin, have low bioavailability, Dr. Gattringer noted at the conference, which was sponsored by the American Society for Microbiology.

The rate of clinical cure – defined as resolution of fever within 72 hours; disappearance of other clinical and laboratory signs of inflammation, including achievement of C-reactive protein level of less than 1 mg/dL; and no need for additional antimicrobial therapy at 10 days – was statistically indistinguishable between the single-dose group and the conventional-regimen group (87.2% vs. 87.9%).

With the single-dose strategy, "you can send the patient home and you can achieve the right level of the drug in the patient," he concluded.

Dr. Gattringer reported having no conflicts of interest related to the trial. The trial was supported by a grant from Pfizer Research, manufacturer of Zithromax (azithromycin).

CHICAGO – Compressing the usual 3-day course of intravenous azithromycin into a single high dose appears to be a safe, efficacious alternative for treating community-acquired pneumonia in adult outpatients.

In an open-label, randomized trial, investigators in Austria compared the same total dose of azithromycin either split over 3 days or given as a single infusion among 72 outpatients with community-acquired pneumonia (CAP).

Trial results, reported at the annual Interscience conference on Antimicrobial Agents and Chemotherapy, showed that the two regimens had similar efficacy and adverse effect profiles. In both groups, nearly 90% of patients were cured.

Photo: ©WILLSIE/iStockphoto.com

The single-dose strategy ensures high levels of the drug independent of patient compliance, according to presenting author Dr. Rainer Gattringer of the Elisabethinen Hospital and Analyse BioLab, both in Linz, Austria. Additionally, it may reduce treatment costs.

"I think maybe physicians are a little bit afraid because it’s not written in the description of the drug that you can use it at 1.5 g as a single dose," he proposed in an interview. "They say, I have no experience with it, and they don’t know about side effects and so on."

But the drug appeared safe and well tolerated with the protocol used in the trial: administration in a liter of infusion solution given over an extended period of 4 hours. "That [protocol] is I think the main thing," Dr. Gattringer said. "So don’t be afraid, try it."

The patients studied were 45 years old, on average, and 65% were men, according to data reported in a poster session. They were fairly healthy, Dr. Gattringer noted; the CRB-65 (confusion, respiratory rate, blood pressure, and age 65 years or older) score was 0, 1, and 2 in 33.3%, 51.4%, and 15.3%, respectively. Overall, 18% had previously received oral antibiotic therapy.

The most common pathogens identified were Streptococcus pneumoniae (22.2% of patients), Mycoplasma pneumoniae (6.9%), Legionella pneumophila (6.9%), Coxiella burnetii (1.4%), and Cytomegalovirus (1.4%). No pathogen was identified in 59.7% of cases.

The patients received either a single IV dose of 1.5 g azithromycin (diluted in 1 L of lactated Ringer solution and given as a 4-hour infusion) or the conventional dose schedule of 500 mg azithromycin IV once daily for 3 days.

Azithromycin is especially useful in patients who have an allergy to beta-lactam antibiotics, and the intravenous formulation is attractive given that oral macrolides, including azithromycin, have low bioavailability, Dr. Gattringer noted at the conference, which was sponsored by the American Society for Microbiology.

The rate of clinical cure – defined as resolution of fever within 72 hours; disappearance of other clinical and laboratory signs of inflammation, including achievement of C-reactive protein level of less than 1 mg/dL; and no need for additional antimicrobial therapy at 10 days – was statistically indistinguishable between the single-dose group and the conventional-regimen group (87.2% vs. 87.9%).

With the single-dose strategy, "you can send the patient home and you can achieve the right level of the drug in the patient," he concluded.

Dr. Gattringer reported having no conflicts of interest related to the trial. The trial was supported by a grant from Pfizer Research, manufacturer of Zithromax (azithromycin).

CHICAGO – Adults with a bloodstream infection face an increased risk of developing colorectal cancer within 1 year, results from a Canadian study showed.

The organisms associated with the highest risk of new colorectal cancer were Clostridium spp., the Bacteroides fragilis group, and other anaerobes, Dr. Sanchia Warren reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. However, Streptococcus bovis, which has been proposed as a marker of colorectal malignancy, was not found to be associated with increased diagnoses of the condition.

"If patients have a bloodstream infection, particularly older patients, you should definitely be looking for signs of colorectal cancer," Dr. Warren said in an interview at the meeting, which was sponsored by the American Society for Microbiology. "We did not look at premalignant conditions such as polyps. If we did, I suspect that we would have had even stronger findings."

Dr. Warren, who conducted the research during an infectious diseases fellowship at the University of Calgary (Alta.), and her associates used a regional electronic surveillance system database to identify a cohort of Calgary area adults who had an incident bloodstream infection between 2000 and 2007. They used a computer program to match the patients to the Alberta Cancer Registry.

Over the 7-year period, 10,121 bloodstream infections occurred in 8,806 patients. The mean age of the patients was 62 years, and 54% were male. During the same time frame, 3,859 residents in the region were diagnosed with colorectal cancer, of which 349 followed a bloodstream infection.

The researchers found that 71 patients had a diagnosis of colorectal cancer made at the same time as or within 1 year following a bloodstream infection, for a standardized incidence ratio of 14.4 compared with the general population. Organisms associated with the highest risk of new colorectal cancer diagnosis were Clostridium spp. (standardized incidence ratio, 115.39), the Bacteroides fragilis group (SIR, 77.2), and other gram positive anaerobes (SIR, 47.7).

Advancing age, male gender, liver disease, and a higher Charlson Index score were associated with bloodstream infections and a new diagnosis of colorectal cancer.

Dr. Warren, who is currently a medical microbiology registrar at St. Vincent’s Hospital, Fitzroy, Australia, said that she and her associates are conducting a further review of patients with a Streptococcus bovis bloodstream infection. They also hope to determine what percentage of patients underwent colonoscopy.

She acknowledged certain limitations of the study, including the potential for missed cases during database matching, as well as the relatively small sample size of patients used in the final analysis.

Dr. Warren said that she had no relevant financial conflicts to disclose.

CHICAGO – Adults with a bloodstream infection face an increased risk of developing colorectal cancer within 1 year, results from a Canadian study showed.

The organisms associated with the highest risk of new colorectal cancer were Clostridium spp., the Bacteroides fragilis group, and other anaerobes, Dr. Sanchia Warren reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. However, Streptococcus bovis, which has been proposed as a marker of colorectal malignancy, was not found to be associated with increased diagnoses of the condition.

"If patients have a bloodstream infection, particularly older patients, you should definitely be looking for signs of colorectal cancer," Dr. Warren said in an interview at the meeting, which was sponsored by the American Society for Microbiology. "We did not look at premalignant conditions such as polyps. If we did, I suspect that we would have had even stronger findings."

Dr. Warren, who conducted the research during an infectious diseases fellowship at the University of Calgary (Alta.), and her associates used a regional electronic surveillance system database to identify a cohort of Calgary area adults who had an incident bloodstream infection between 2000 and 2007. They used a computer program to match the patients to the Alberta Cancer Registry.

Over the 7-year period, 10,121 bloodstream infections occurred in 8,806 patients. The mean age of the patients was 62 years, and 54% were male. During the same time frame, 3,859 residents in the region were diagnosed with colorectal cancer, of which 349 followed a bloodstream infection.

The researchers found that 71 patients had a diagnosis of colorectal cancer made at the same time as or within 1 year following a bloodstream infection, for a standardized incidence ratio of 14.4 compared with the general population. Organisms associated with the highest risk of new colorectal cancer diagnosis were Clostridium spp. (standardized incidence ratio, 115.39), the Bacteroides fragilis group (SIR, 77.2), and other gram positive anaerobes (SIR, 47.7).

Advancing age, male gender, liver disease, and a higher Charlson Index score were associated with bloodstream infections and a new diagnosis of colorectal cancer.

Dr. Warren, who is currently a medical microbiology registrar at St. Vincent’s Hospital, Fitzroy, Australia, said that she and her associates are conducting a further review of patients with a Streptococcus bovis bloodstream infection. They also hope to determine what percentage of patients underwent colonoscopy.

She acknowledged certain limitations of the study, including the potential for missed cases during database matching, as well as the relatively small sample size of patients used in the final analysis.

Dr. Warren said that she had no relevant financial conflicts to disclose.

CHICAGO – Adults with a bloodstream infection face an increased risk of developing colorectal cancer within 1 year, results from a Canadian study showed.

The organisms associated with the highest risk of new colorectal cancer were Clostridium spp., the Bacteroides fragilis group, and other anaerobes, Dr. Sanchia Warren reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. However, Streptococcus bovis, which has been proposed as a marker of colorectal malignancy, was not found to be associated with increased diagnoses of the condition.

"If patients have a bloodstream infection, particularly older patients, you should definitely be looking for signs of colorectal cancer," Dr. Warren said in an interview at the meeting, which was sponsored by the American Society for Microbiology. "We did not look at premalignant conditions such as polyps. If we did, I suspect that we would have had even stronger findings."

Dr. Warren, who conducted the research during an infectious diseases fellowship at the University of Calgary (Alta.), and her associates used a regional electronic surveillance system database to identify a cohort of Calgary area adults who had an incident bloodstream infection between 2000 and 2007. They used a computer program to match the patients to the Alberta Cancer Registry.

Over the 7-year period, 10,121 bloodstream infections occurred in 8,806 patients. The mean age of the patients was 62 years, and 54% were male. During the same time frame, 3,859 residents in the region were diagnosed with colorectal cancer, of which 349 followed a bloodstream infection.

The researchers found that 71 patients had a diagnosis of colorectal cancer made at the same time as or within 1 year following a bloodstream infection, for a standardized incidence ratio of 14.4 compared with the general population. Organisms associated with the highest risk of new colorectal cancer diagnosis were Clostridium spp. (standardized incidence ratio, 115.39), the Bacteroides fragilis group (SIR, 77.2), and other gram positive anaerobes (SIR, 47.7).

Advancing age, male gender, liver disease, and a higher Charlson Index score were associated with bloodstream infections and a new diagnosis of colorectal cancer.

Dr. Warren, who is currently a medical microbiology registrar at St. Vincent’s Hospital, Fitzroy, Australia, said that she and her associates are conducting a further review of patients with a Streptococcus bovis bloodstream infection. They also hope to determine what percentage of patients underwent colonoscopy.

She acknowledged certain limitations of the study, including the potential for missed cases during database matching, as well as the relatively small sample size of patients used in the final analysis.

Dr. Warren said that she had no relevant financial conflicts to disclose.

CHICAGO – The incidence of Clostridium difficile–associated disease was more than three times higher among patients using proton pump inhibitors compared with those who were not, results from a large Japanese study found.

"In addition to previous use of antimicrobials, long-term use of proton pump inhibitors [PPIs] is pointed out as a risk factor" of C. difficile–associated disease (CDAD), researchers led by Dr. Takatoshi Kitazawa reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "However, most previous epidemiological studies that showed [a] positive relationship between PPI use and CDAD were conducted retrospectively and in Western countries. In this study, we investigated whether the use of PPIs increases the incidence of CDAD at a single institution in Japan."

Dr. Kitazawa of Teikyo University, Tokyo, and his associates evaluated the medical records of 793 patients who were admitted to the university’s department of medicine between April and June of 2009. They defined PPI users as those who were prescribed a PPI for more than 30 days. CDAD was defined as detection of C. difficile toxin from stool samples in patients with diarrhea. Use of immunosuppressants was defined as using more than 20 mg of prednisolone and other agents in this class for more than 30 days. A long hospital stay was defined as one that extended 30 days.

PPI users were older than non-PPI users (mean, 69 years vs. 63 years, respectively; P less than .01) and a higher proportion were men (69% vs. 58%; P = .04).

The researchers identified CDAD in 19 (3.9%) of the 487 PPI users and in 4 (1.3%) of the 304 non-PPI users. This translated into a relative risk of PPI use on the incidence of CDAD that reached 3.20 (P = .04).

On multivariate analysis controlling for age; sex; use of antibiotics and H₂ receptor agonists; and long hospital and ICU stay, the researchers noted no significant differences in the incidence of CDAD between PPI users and non-PPI users because of missing data.

Dr. Kitazawa said that he had no relevant financial conflicts to disclose. The meeting was sponsored by the American Society for Microbiology.

CHICAGO – The incidence of Clostridium difficile–associated disease was more than three times higher among patients using proton pump inhibitors compared with those who were not, results from a large Japanese study found.

"In addition to previous use of antimicrobials, long-term use of proton pump inhibitors [PPIs] is pointed out as a risk factor" of C. difficile–associated disease (CDAD), researchers led by Dr. Takatoshi Kitazawa reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "However, most previous epidemiological studies that showed [a] positive relationship between PPI use and CDAD were conducted retrospectively and in Western countries. In this study, we investigated whether the use of PPIs increases the incidence of CDAD at a single institution in Japan."

Dr. Kitazawa of Teikyo University, Tokyo, and his associates evaluated the medical records of 793 patients who were admitted to the university’s department of medicine between April and June of 2009. They defined PPI users as those who were prescribed a PPI for more than 30 days. CDAD was defined as detection of C. difficile toxin from stool samples in patients with diarrhea. Use of immunosuppressants was defined as using more than 20 mg of prednisolone and other agents in this class for more than 30 days. A long hospital stay was defined as one that extended 30 days.

PPI users were older than non-PPI users (mean, 69 years vs. 63 years, respectively; P less than .01) and a higher proportion were men (69% vs. 58%; P = .04).

The researchers identified CDAD in 19 (3.9%) of the 487 PPI users and in 4 (1.3%) of the 304 non-PPI users. This translated into a relative risk of PPI use on the incidence of CDAD that reached 3.20 (P = .04).

On multivariate analysis controlling for age; sex; use of antibiotics and H₂ receptor agonists; and long hospital and ICU stay, the researchers noted no significant differences in the incidence of CDAD between PPI users and non-PPI users because of missing data.

Dr. Kitazawa said that he had no relevant financial conflicts to disclose. The meeting was sponsored by the American Society for Microbiology.

CHICAGO – The incidence of Clostridium difficile–associated disease was more than three times higher among patients using proton pump inhibitors compared with those who were not, results from a large Japanese study found.

"In addition to previous use of antimicrobials, long-term use of proton pump inhibitors [PPIs] is pointed out as a risk factor" of C. difficile–associated disease (CDAD), researchers led by Dr. Takatoshi Kitazawa reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "However, most previous epidemiological studies that showed [a] positive relationship between PPI use and CDAD were conducted retrospectively and in Western countries. In this study, we investigated whether the use of PPIs increases the incidence of CDAD at a single institution in Japan."

Dr. Kitazawa of Teikyo University, Tokyo, and his associates evaluated the medical records of 793 patients who were admitted to the university’s department of medicine between April and June of 2009. They defined PPI users as those who were prescribed a PPI for more than 30 days. CDAD was defined as detection of C. difficile toxin from stool samples in patients with diarrhea. Use of immunosuppressants was defined as using more than 20 mg of prednisolone and other agents in this class for more than 30 days. A long hospital stay was defined as one that extended 30 days.

PPI users were older than non-PPI users (mean, 69 years vs. 63 years, respectively; P less than .01) and a higher proportion were men (69% vs. 58%; P = .04).

The researchers identified CDAD in 19 (3.9%) of the 487 PPI users and in 4 (1.3%) of the 304 non-PPI users. This translated into a relative risk of PPI use on the incidence of CDAD that reached 3.20 (P = .04).

On multivariate analysis controlling for age; sex; use of antibiotics and H₂ receptor agonists; and long hospital and ICU stay, the researchers noted no significant differences in the incidence of CDAD between PPI users and non-PPI users because of missing data.

Dr. Kitazawa said that he had no relevant financial conflicts to disclose. The meeting was sponsored by the American Society for Microbiology.

CHICAGO – Nearly one-third of patients diagnosed with Clostridium difficile infection in the previous 2 months had positive rectal cultures during follow-up visits to outpatient clinics.

Acquisition of C. difficile spores on gloved hands occurred often, especially after contact with skin sites, Lucy A. Jury reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

"Charts of patients who have a C. difficile infection in the past 2 months should be flagged before they come to the outpatient clinic," Ms. Jury, a nurse practitioner with the Geriatric Research Education and Clinical Center at the Cleveland Veterans Affairs Medical Center, advised in an interview. "After they leave the exam room, that room should be bleached out and providers should wash their hands between seeing patients. Clean where the patient was sitting, and any surfaces the patient came into contact with."

She and her associates performed a 4-month prospective study of 35 C. difficile patients diagnosed in the prior 2 months and subsequently seen in outpatient clinics affiliated with the Cleveland VA Medical Center. The researchers obtained rectal swab cultures from all patients, as well as gloved hand print cultures after contacting the patients’ skin (abdomen, chest, arm, and hand) and environmental sites (exam room chair, exam table, and physician work area).

The mean age of the 35 patients was 66 years, 33 (94%) were male, and 7 (20%) resided in long term care facilities. Ms. Jury reported that 7 of the patients (20%) were still on C. difficile therapy, 3 (9%) had diarrhea, and 11 (31%) had positive rectal cultures.

Acquisition of spores on gloved hands occurred often, particularly after contact with any skin site (45%), followed by the hand (23%), chest (20%), abdomen (16%), and arm (14%). Spores were also detected on environmental sites (20%), especially the examination table (19%) and the chair used by patients in the examination room (5%).

For positive glove print cultures, Ms. Jury said that the mean numbers of colonies acquired after contact with skin and environmental sites were 18 and 5, respectively.

The conference was sponsored by the American Society for Microbiology. Ms. Jury said that she had no disclosures.

CHICAGO – Nearly one-third of patients diagnosed with Clostridium difficile infection in the previous 2 months had positive rectal cultures during follow-up visits to outpatient clinics.

Acquisition of C. difficile spores on gloved hands occurred often, especially after contact with skin sites, Lucy A. Jury reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

"Charts of patients who have a C. difficile infection in the past 2 months should be flagged before they come to the outpatient clinic," Ms. Jury, a nurse practitioner with the Geriatric Research Education and Clinical Center at the Cleveland Veterans Affairs Medical Center, advised in an interview. "After they leave the exam room, that room should be bleached out and providers should wash their hands between seeing patients. Clean where the patient was sitting, and any surfaces the patient came into contact with."

She and her associates performed a 4-month prospective study of 35 C. difficile patients diagnosed in the prior 2 months and subsequently seen in outpatient clinics affiliated with the Cleveland VA Medical Center. The researchers obtained rectal swab cultures from all patients, as well as gloved hand print cultures after contacting the patients’ skin (abdomen, chest, arm, and hand) and environmental sites (exam room chair, exam table, and physician work area).

The mean age of the 35 patients was 66 years, 33 (94%) were male, and 7 (20%) resided in long term care facilities. Ms. Jury reported that 7 of the patients (20%) were still on C. difficile therapy, 3 (9%) had diarrhea, and 11 (31%) had positive rectal cultures.

Acquisition of spores on gloved hands occurred often, particularly after contact with any skin site (45%), followed by the hand (23%), chest (20%), abdomen (16%), and arm (14%). Spores were also detected on environmental sites (20%), especially the examination table (19%) and the chair used by patients in the examination room (5%).

For positive glove print cultures, Ms. Jury said that the mean numbers of colonies acquired after contact with skin and environmental sites were 18 and 5, respectively.

The conference was sponsored by the American Society for Microbiology. Ms. Jury said that she had no disclosures.

CHICAGO – Nearly one-third of patients diagnosed with Clostridium difficile infection in the previous 2 months had positive rectal cultures during follow-up visits to outpatient clinics.

Acquisition of C. difficile spores on gloved hands occurred often, especially after contact with skin sites, Lucy A. Jury reported during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

"Charts of patients who have a C. difficile infection in the past 2 months should be flagged before they come to the outpatient clinic," Ms. Jury, a nurse practitioner with the Geriatric Research Education and Clinical Center at the Cleveland Veterans Affairs Medical Center, advised in an interview. "After they leave the exam room, that room should be bleached out and providers should wash their hands between seeing patients. Clean where the patient was sitting, and any surfaces the patient came into contact with."

She and her associates performed a 4-month prospective study of 35 C. difficile patients diagnosed in the prior 2 months and subsequently seen in outpatient clinics affiliated with the Cleveland VA Medical Center. The researchers obtained rectal swab cultures from all patients, as well as gloved hand print cultures after contacting the patients’ skin (abdomen, chest, arm, and hand) and environmental sites (exam room chair, exam table, and physician work area).

The mean age of the 35 patients was 66 years, 33 (94%) were male, and 7 (20%) resided in long term care facilities. Ms. Jury reported that 7 of the patients (20%) were still on C. difficile therapy, 3 (9%) had diarrhea, and 11 (31%) had positive rectal cultures.

Acquisition of spores on gloved hands occurred often, particularly after contact with any skin site (45%), followed by the hand (23%), chest (20%), abdomen (16%), and arm (14%). Spores were also detected on environmental sites (20%), especially the examination table (19%) and the chair used by patients in the examination room (5%).

For positive glove print cultures, Ms. Jury said that the mean numbers of colonies acquired after contact with skin and environmental sites were 18 and 5, respectively.

The conference was sponsored by the American Society for Microbiology. Ms. Jury said that she had no disclosures.

CHICAGO – Moxifloxacin works as well as the combination of amoxicillin and clavulanic acid in the treatment of acute exacerbations of complicated chronic obstructive pulmonary disease, new data show. But the former may have the edge in cases in which a bacterial pathogen is identified.

In a randomized, double-blind, noninferiority trial among 1,352 patients who had complicated COPD and an exacerbation, about a fifth of patients had a clinical failure of their antibiotic therapy, no matter which regimen they received, according to results reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

However, secondary analyses showed that in the subset of patients in whom a bacterial pathogen was identified in sputum before antibiotic therapy was started, clinical failure was significantly less likely for those who received moxifloxacin, which is a member of the fluoroquinolone class of antibiotics.

"I think, clinically, what this translates to is, yes, you can use either antibiotic in this group," lead investigator Dr. Sanjay Sethi said in an interview at the conference, which was sponsored by the American Society for Microbiology. But in patients in whom a bacterial pathogen is identified or strongly suspected, "Moxifloxacin does better in that subgroup."

The difference seems to be driven by better bacterial eradication with moxifloxacin, he added. "So when you have a well-defined pathogen, you eradicate the bacterium [and] you get a clinical difference in outcomes."

Both antibiotics were well tolerated, according to Dr. Sethi. Moxifloxacin may have a slight advantage in terms of convenience, as it was given once daily for 5 days, compared with twice daily for 7 days for the amoxicillin–clavulanic acid. Comparative costs will depend on the local market and availability of generic formulations.

Dr. Sethi uses the quinolones as well as amoxicillin plus clavulanic acid. When he is clinically sure that a patient has a predominant pathogen, or when a biomarker such as a C-reactive protein or procalcitonin level indicates "that this could very likely be bacterial, then I would tend to go for the ‘moxi,’ " based on such data, he added.

Some guidelines, such as the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines, list the two antibiotic regimens as equal alternatives for patients with complicated COPD, such as those having underlying severe airflow obstruction, recurrent exacerbations, or comorbid cardiac disease, according to Dr. Sethi, chief of the division of pulmonary, critical care, and sleep medicine at the State University of New York at Buffalo.

"What this study tells me is, I think that we did that right," that is, listing the two regimens as alternatives, he commented. "These are secondary analyses, but there could be a subgroup with a predominant pathogen [in whom] there may be differences between the two."

In a novel finding, the study also showed that early bacterial eradication at the end of antibiotic therapy increased the likelihood of clinical cure at 8 weeks later, no matter which antibiotic the patients received. This association "has not been very well described in COPD exacerbations," Dr. Sethi noted.

Patients with COPD were eligible for the trial, called MAESTRAL (Moxifloxacin vs. Amoxicillin–Clavulanic Acid in Treatment of Acute Exacerbation of Chronic Bronchitis), if they were aged 60 years or older, had an Anthonisen type 1 exacerbation (with purulent sputum, increased sputum volume, and increased dyspnea), had an forced expiratory volume in 1 second (FEV₁) of less than or equal to 60% of predicted, and had experienced more than two exacerbations in the last year that required systemic antibiotics and/or systemic corticosteroids.

The subjects were randomized in equal numbers to receive moxifloxacin (400 mg orally once daily for 5 days), or amoxicillin plus clavulanic acid (875 and 125 mg orally twice daily for 7 days). Sputum samples were collected before start of therapy and serially thereafter for Gram staining and culture.

The trial’s primary end point was the rate of clinical failure (defined as the need for additional or alternative treatment for the exacerbation with systemic antibiotics, systemic corticosteroids, and/or hospitalization) within 8 weeks of the end of antibiotic therapy. The investigators defined noninferiority as a difference in the rate of this end point of no more than 6% between groups.

The patients studied were 70 years old on average, and 80% were men. Slightly more than a third used systemic corticosteroids. Their mean FEV₁ was about 980 mL, and their mean number of exacerbations in the previous year had been 2.5.

Study results, reported in a poster session, showed that the rate of clinical failure was noninferior with moxifloxacin, compared with amoxicillin–clavulanic acid, in both the intent-to-treat population (20.4% vs. 21.6%) and the per-protocol population (20.6% vs. 22.0%).

Slightly fewer than half of patients had at least one potentially pathogenic bacterium isolated from sputum before starting antibiotic therapy, most often Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus.

In this subset of patients, the rate of clinical failure was lower with moxifloxacin than with amoxicillin–clavulanic acid in both the intent-to-treat population (19.0% vs. 25.4%; P = .02) and the per-protocol population (19.2% vs. 26.1%; P = .03). Further analysis showed higher rates of bacterial eradication with moxifloxacin, mainly driven by higher rates of eradication of H. influenzae (89.2% vs. 66.7%).

In the study population overall, patients who had bacteriologic eradication at the end of antibiotic therapy, compared with bacteriologic persistence or superinfection, were more likely to be cured 8 weeks later (79.7% vs. 54.7%; P less than .001). The finding was the same in the two treatment groups individually.

The rate of drug-related adverse events was 7.8% with moxifloxacin and 6.1% with amoxicillin–clavulanic acid. The most common events were headache, diarrhea, and fever.

Dr. Sethi reported that he is an investigator for and scientific advisor to Bayer HealthCare Pharmaceuticals, which manufactured the moxifloxacin, and has received speaker honoraria and consulting fees from the company. The trial was supported by Bayer HealthCare Pharmaceuticals.

CHICAGO – Moxifloxacin works as well as the combination of amoxicillin and clavulanic acid in the treatment of acute exacerbations of complicated chronic obstructive pulmonary disease, new data show. But the former may have the edge in cases in which a bacterial pathogen is identified.

In a randomized, double-blind, noninferiority trial among 1,352 patients who had complicated COPD and an exacerbation, about a fifth of patients had a clinical failure of their antibiotic therapy, no matter which regimen they received, according to results reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

However, secondary analyses showed that in the subset of patients in whom a bacterial pathogen was identified in sputum before antibiotic therapy was started, clinical failure was significantly less likely for those who received moxifloxacin, which is a member of the fluoroquinolone class of antibiotics.

"I think, clinically, what this translates to is, yes, you can use either antibiotic in this group," lead investigator Dr. Sanjay Sethi said in an interview at the conference, which was sponsored by the American Society for Microbiology. But in patients in whom a bacterial pathogen is identified or strongly suspected, "Moxifloxacin does better in that subgroup."

The difference seems to be driven by better bacterial eradication with moxifloxacin, he added. "So when you have a well-defined pathogen, you eradicate the bacterium [and] you get a clinical difference in outcomes."

Both antibiotics were well tolerated, according to Dr. Sethi. Moxifloxacin may have a slight advantage in terms of convenience, as it was given once daily for 5 days, compared with twice daily for 7 days for the amoxicillin–clavulanic acid. Comparative costs will depend on the local market and availability of generic formulations.

Dr. Sethi uses the quinolones as well as amoxicillin plus clavulanic acid. When he is clinically sure that a patient has a predominant pathogen, or when a biomarker such as a C-reactive protein or procalcitonin level indicates "that this could very likely be bacterial, then I would tend to go for the ‘moxi,’ " based on such data, he added.

Some guidelines, such as the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines, list the two antibiotic regimens as equal alternatives for patients with complicated COPD, such as those having underlying severe airflow obstruction, recurrent exacerbations, or comorbid cardiac disease, according to Dr. Sethi, chief of the division of pulmonary, critical care, and sleep medicine at the State University of New York at Buffalo.

"What this study tells me is, I think that we did that right," that is, listing the two regimens as alternatives, he commented. "These are secondary analyses, but there could be a subgroup with a predominant pathogen [in whom] there may be differences between the two."

In a novel finding, the study also showed that early bacterial eradication at the end of antibiotic therapy increased the likelihood of clinical cure at 8 weeks later, no matter which antibiotic the patients received. This association "has not been very well described in COPD exacerbations," Dr. Sethi noted.

Patients with COPD were eligible for the trial, called MAESTRAL (Moxifloxacin vs. Amoxicillin–Clavulanic Acid in Treatment of Acute Exacerbation of Chronic Bronchitis), if they were aged 60 years or older, had an Anthonisen type 1 exacerbation (with purulent sputum, increased sputum volume, and increased dyspnea), had an forced expiratory volume in 1 second (FEV₁) of less than or equal to 60% of predicted, and had experienced more than two exacerbations in the last year that required systemic antibiotics and/or systemic corticosteroids.

The subjects were randomized in equal numbers to receive moxifloxacin (400 mg orally once daily for 5 days), or amoxicillin plus clavulanic acid (875 and 125 mg orally twice daily for 7 days). Sputum samples were collected before start of therapy and serially thereafter for Gram staining and culture.

The trial’s primary end point was the rate of clinical failure (defined as the need for additional or alternative treatment for the exacerbation with systemic antibiotics, systemic corticosteroids, and/or hospitalization) within 8 weeks of the end of antibiotic therapy. The investigators defined noninferiority as a difference in the rate of this end point of no more than 6% between groups.

The patients studied were 70 years old on average, and 80% were men. Slightly more than a third used systemic corticosteroids. Their mean FEV₁ was about 980 mL, and their mean number of exacerbations in the previous year had been 2.5.

Study results, reported in a poster session, showed that the rate of clinical failure was noninferior with moxifloxacin, compared with amoxicillin–clavulanic acid, in both the intent-to-treat population (20.4% vs. 21.6%) and the per-protocol population (20.6% vs. 22.0%).

Slightly fewer than half of patients had at least one potentially pathogenic bacterium isolated from sputum before starting antibiotic therapy, most often Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus.

In this subset of patients, the rate of clinical failure was lower with moxifloxacin than with amoxicillin–clavulanic acid in both the intent-to-treat population (19.0% vs. 25.4%; P = .02) and the per-protocol population (19.2% vs. 26.1%; P = .03). Further analysis showed higher rates of bacterial eradication with moxifloxacin, mainly driven by higher rates of eradication of H. influenzae (89.2% vs. 66.7%).

In the study population overall, patients who had bacteriologic eradication at the end of antibiotic therapy, compared with bacteriologic persistence or superinfection, were more likely to be cured 8 weeks later (79.7% vs. 54.7%; P less than .001). The finding was the same in the two treatment groups individually.

The rate of drug-related adverse events was 7.8% with moxifloxacin and 6.1% with amoxicillin–clavulanic acid. The most common events were headache, diarrhea, and fever.

Dr. Sethi reported that he is an investigator for and scientific advisor to Bayer HealthCare Pharmaceuticals, which manufactured the moxifloxacin, and has received speaker honoraria and consulting fees from the company. The trial was supported by Bayer HealthCare Pharmaceuticals.

CHICAGO – Moxifloxacin works as well as the combination of amoxicillin and clavulanic acid in the treatment of acute exacerbations of complicated chronic obstructive pulmonary disease, new data show. But the former may have the edge in cases in which a bacterial pathogen is identified.

In a randomized, double-blind, noninferiority trial among 1,352 patients who had complicated COPD and an exacerbation, about a fifth of patients had a clinical failure of their antibiotic therapy, no matter which regimen they received, according to results reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

However, secondary analyses showed that in the subset of patients in whom a bacterial pathogen was identified in sputum before antibiotic therapy was started, clinical failure was significantly less likely for those who received moxifloxacin, which is a member of the fluoroquinolone class of antibiotics.

"I think, clinically, what this translates to is, yes, you can use either antibiotic in this group," lead investigator Dr. Sanjay Sethi said in an interview at the conference, which was sponsored by the American Society for Microbiology. But in patients in whom a bacterial pathogen is identified or strongly suspected, "Moxifloxacin does better in that subgroup."

The difference seems to be driven by better bacterial eradication with moxifloxacin, he added. "So when you have a well-defined pathogen, you eradicate the bacterium [and] you get a clinical difference in outcomes."

Both antibiotics were well tolerated, according to Dr. Sethi. Moxifloxacin may have a slight advantage in terms of convenience, as it was given once daily for 5 days, compared with twice daily for 7 days for the amoxicillin–clavulanic acid. Comparative costs will depend on the local market and availability of generic formulations.

Dr. Sethi uses the quinolones as well as amoxicillin plus clavulanic acid. When he is clinically sure that a patient has a predominant pathogen, or when a biomarker such as a C-reactive protein or procalcitonin level indicates "that this could very likely be bacterial, then I would tend to go for the ‘moxi,’ " based on such data, he added.

Some guidelines, such as the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines, list the two antibiotic regimens as equal alternatives for patients with complicated COPD, such as those having underlying severe airflow obstruction, recurrent exacerbations, or comorbid cardiac disease, according to Dr. Sethi, chief of the division of pulmonary, critical care, and sleep medicine at the State University of New York at Buffalo.

"What this study tells me is, I think that we did that right," that is, listing the two regimens as alternatives, he commented. "These are secondary analyses, but there could be a subgroup with a predominant pathogen [in whom] there may be differences between the two."

In a novel finding, the study also showed that early bacterial eradication at the end of antibiotic therapy increased the likelihood of clinical cure at 8 weeks later, no matter which antibiotic the patients received. This association "has not been very well described in COPD exacerbations," Dr. Sethi noted.

Patients with COPD were eligible for the trial, called MAESTRAL (Moxifloxacin vs. Amoxicillin–Clavulanic Acid in Treatment of Acute Exacerbation of Chronic Bronchitis), if they were aged 60 years or older, had an Anthonisen type 1 exacerbation (with purulent sputum, increased sputum volume, and increased dyspnea), had an forced expiratory volume in 1 second (FEV₁) of less than or equal to 60% of predicted, and had experienced more than two exacerbations in the last year that required systemic antibiotics and/or systemic corticosteroids.

The subjects were randomized in equal numbers to receive moxifloxacin (400 mg orally once daily for 5 days), or amoxicillin plus clavulanic acid (875 and 125 mg orally twice daily for 7 days). Sputum samples were collected before start of therapy and serially thereafter for Gram staining and culture.

The trial’s primary end point was the rate of clinical failure (defined as the need for additional or alternative treatment for the exacerbation with systemic antibiotics, systemic corticosteroids, and/or hospitalization) within 8 weeks of the end of antibiotic therapy. The investigators defined noninferiority as a difference in the rate of this end point of no more than 6% between groups.

The patients studied were 70 years old on average, and 80% were men. Slightly more than a third used systemic corticosteroids. Their mean FEV₁ was about 980 mL, and their mean number of exacerbations in the previous year had been 2.5.

Study results, reported in a poster session, showed that the rate of clinical failure was noninferior with moxifloxacin, compared with amoxicillin–clavulanic acid, in both the intent-to-treat population (20.4% vs. 21.6%) and the per-protocol population (20.6% vs. 22.0%).

Slightly fewer than half of patients had at least one potentially pathogenic bacterium isolated from sputum before starting antibiotic therapy, most often Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus.

In this subset of patients, the rate of clinical failure was lower with moxifloxacin than with amoxicillin–clavulanic acid in both the intent-to-treat population (19.0% vs. 25.4%; P = .02) and the per-protocol population (19.2% vs. 26.1%; P = .03). Further analysis showed higher rates of bacterial eradication with moxifloxacin, mainly driven by higher rates of eradication of H. influenzae (89.2% vs. 66.7%).

In the study population overall, patients who had bacteriologic eradication at the end of antibiotic therapy, compared with bacteriologic persistence or superinfection, were more likely to be cured 8 weeks later (79.7% vs. 54.7%; P less than .001). The finding was the same in the two treatment groups individually.

The rate of drug-related adverse events was 7.8% with moxifloxacin and 6.1% with amoxicillin–clavulanic acid. The most common events were headache, diarrhea, and fever.

Dr. Sethi reported that he is an investigator for and scientific advisor to Bayer HealthCare Pharmaceuticals, which manufactured the moxifloxacin, and has received speaker honoraria and consulting fees from the company. The trial was supported by Bayer HealthCare Pharmaceuticals.

CHICAGO – A simple clinical prediction rule effectively detected a majority of asymptomatic carriers of Clostridium difficile infection in a long-term care facility, results from a small single-center study found.

According to the rule, which was derived from an article in the infectious diseases literature, previous C. difficile infection and/or antibiotic therapy within the past 3 months is helpful in predicting asymptomatic carriers (Clin. Infect. Dis. 2007;45:992-8). During a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy, which was sponsored by the American Society for Microbiology, the researchers, led by Lucy Jury, presented findings from a study that set out to test the value of the prediction rule in a long-term care setting.

Ms. Jury, a nurse practitioner with the geriatric research, education, and clinical center at the Louis Stokes Cleveland Veterans Affairs Medical Center, and her associates conducted a 5-month prospective study of 120 patients who were being transferred from the Cleveland VA hospital to an affiliated long-term care facility. Rectal swabs were cultured at the time of transfer and then weekly for up to 6 weeks. The mean age of patients was 69 years, all were men, 75% had received antibiotic therapy in the past 3 months, and 39% had an indwelling catheter.

Of the 120 patients, 14 (12%) were asymptomatically colonized upon transfer to the long-term care facility. Among 85 patients with negative cultures and at least one follow-up culture, 22 (26%) acquired colonization.

Ms. Jury and her associates determined that the prediction rule had a sensitivity of 78%, a specificity of 43%, a positive predictive value of 49%, and a negative predictive value of 73%. When the researchers limited their analysis to high-risk antibiotics – including third-generation cephalosporins, fluoroquinolones, and clindamycin – the specificity rose to 82%, but the sensitivity fell to 55%.

In their poster, the researchers concluded that the prediction rule "could be used to guide infection-control interventions designed to reduce the risk for transmission from asymptomatic carriers."

Ms. Jury said that she had no relevant financial disclosures to make.

CHICAGO – A simple clinical prediction rule effectively detected a majority of asymptomatic carriers of Clostridium difficile infection in a long-term care facility, results from a small single-center study found.

According to the rule, which was derived from an article in the infectious diseases literature, previous C. difficile infection and/or antibiotic therapy within the past 3 months is helpful in predicting asymptomatic carriers (Clin. Infect. Dis. 2007;45:992-8). During a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy, which was sponsored by the American Society for Microbiology, the researchers, led by Lucy Jury, presented findings from a study that set out to test the value of the prediction rule in a long-term care setting.

Ms. Jury, a nurse practitioner with the geriatric research, education, and clinical center at the Louis Stokes Cleveland Veterans Affairs Medical Center, and her associates conducted a 5-month prospective study of 120 patients who were being transferred from the Cleveland VA hospital to an affiliated long-term care facility. Rectal swabs were cultured at the time of transfer and then weekly for up to 6 weeks. The mean age of patients was 69 years, all were men, 75% had received antibiotic therapy in the past 3 months, and 39% had an indwelling catheter.

Of the 120 patients, 14 (12%) were asymptomatically colonized upon transfer to the long-term care facility. Among 85 patients with negative cultures and at least one follow-up culture, 22 (26%) acquired colonization.

Ms. Jury and her associates determined that the prediction rule had a sensitivity of 78%, a specificity of 43%, a positive predictive value of 49%, and a negative predictive value of 73%. When the researchers limited their analysis to high-risk antibiotics – including third-generation cephalosporins, fluoroquinolones, and clindamycin – the specificity rose to 82%, but the sensitivity fell to 55%.

In their poster, the researchers concluded that the prediction rule "could be used to guide infection-control interventions designed to reduce the risk for transmission from asymptomatic carriers."

Ms. Jury said that she had no relevant financial disclosures to make.

CHICAGO – A simple clinical prediction rule effectively detected a majority of asymptomatic carriers of Clostridium difficile infection in a long-term care facility, results from a small single-center study found.

According to the rule, which was derived from an article in the infectious diseases literature, previous C. difficile infection and/or antibiotic therapy within the past 3 months is helpful in predicting asymptomatic carriers (Clin. Infect. Dis. 2007;45:992-8). During a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy, which was sponsored by the American Society for Microbiology, the researchers, led by Lucy Jury, presented findings from a study that set out to test the value of the prediction rule in a long-term care setting.

Ms. Jury, a nurse practitioner with the geriatric research, education, and clinical center at the Louis Stokes Cleveland Veterans Affairs Medical Center, and her associates conducted a 5-month prospective study of 120 patients who were being transferred from the Cleveland VA hospital to an affiliated long-term care facility. Rectal swabs were cultured at the time of transfer and then weekly for up to 6 weeks. The mean age of patients was 69 years, all were men, 75% had received antibiotic therapy in the past 3 months, and 39% had an indwelling catheter.

Of the 120 patients, 14 (12%) were asymptomatically colonized upon transfer to the long-term care facility. Among 85 patients with negative cultures and at least one follow-up culture, 22 (26%) acquired colonization.

Ms. Jury and her associates determined that the prediction rule had a sensitivity of 78%, a specificity of 43%, a positive predictive value of 49%, and a negative predictive value of 73%. When the researchers limited their analysis to high-risk antibiotics – including third-generation cephalosporins, fluoroquinolones, and clindamycin – the specificity rose to 82%, but the sensitivity fell to 55%.

In their poster, the researchers concluded that the prediction rule "could be used to guide infection-control interventions designed to reduce the risk for transmission from asymptomatic carriers."

Ms. Jury said that she had no relevant financial disclosures to make.

CHICAGO – Escherichia coli O26 does not appear to cause severe disease in children, according to an epidemiologic study of a recent outbreak in an Oregon child care center.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Shedding in the stool of infected children was prolonged, lasting up to 46 days, but there was no secondary transmission of the pathogen to household members.

Laboratory testing showed that the pathogen produced type 1 Shiga toxin but not type 2 Shiga toxin, which is seen in some other E. coli serotypes and carries a higher risk of hemolytic uremic syndrome.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported

"This study raised more questions than it answered," acknowledged lead investigator Dr. Mathieu Tourdjman, a Centers for Disease Control and Prevention Epidemic Intelligence Service officer with the Oregon Health Authority in Portland. But taken together, the findings generally point to a low-virulence pathogen.

This new information does not warrant any change to Oregon’s policy for child care settings when O26 is detected, according to Dr. Tourdjman. That policy requires that infected children be excluded until they have two consecutive negative stool samples, but allows the local health department to waive the exclusion at its discretion.

"In the context of an O26 Shiga toxin 1–only outbreak in a child care center, we continue to recommend that symptomatic children be excluded at least until symptoms resolve, and that the incidence of infection should be closely monitored," he said. "Routine hand washing before meals and before and after changing diapers and toileting should be emphasized."

And restriction criteria should remain flexible. "In the absence of severe disease, requiring two consecutive negative stool samples to lift the exclusion might not be justifiable," Dr. Tourdjman commented. "And routine testing of asymptomatic children should not be recommended."

Public health officials agree that children with E. coli O157 (the most common serotype) should be excluded from child care until two consecutive negative stool samples are obtained, he noted by way of background. But because of a lack of data, there is no consensus when it comes to restrictions for children with E. coli O26, the second most common serotype.

The Oregon outbreak occurred in October 2010 at a child care center having 76 attendees aged 6 weeks to 12 years, Dr. Tourdjman reported at the conference, which was sponsored by the American Society for Microbiology.

Overall, 61 people – all 13 staff, all 41 attendees in four of five preschool classrooms, and all 7 school-aged siblings of those attendees – provided stool samples for testing.

Results showed that nine of the children and one of the staff were positive for Shiga toxin–producing E. coli O26, as determined by initial polymerase chain reaction for the toxin and confirmed by subsequent stool culture for typing.

Four of the 10 positive individuals, all children, had diarrhea, which was bloody in one case. But none experienced hemolytic uremic syndrome or other serious illness. Laboratory tests showed that all isolates matched and all produced only Shiga toxin type 1.

Of the nine infected children, two had consistently negative test results after their initial positive result. Among the other seven, the median duration of shedding in stool was 25 days, with a maximum of 46 days.

Half of the households of infected children agreed to testing to assess possible secondary transmission, and 14 of 17 household members provided stool samples. None were positive by polymerase chain reaction for Shiga toxin.

In the wake of the outbreak, the child care center was thoroughly cleaned and staff were trained in hygiene practices, according to Dr. Tourdjman. The children with diarrhea were excluded from the center, and the asymptomatic positive children were cohorted (separated from other children in a single classroom).

However, the cohorting was discontinued after 3 weeks given that all factors pointed to a low-virulence pathogen and there was strict compliance with the hygiene practices. "The decision to stop cohorting was not based on the results of the shedding study," he noted. "No symptoms were reported at the center after the discontinuation of cohorting."

Dr. Tourdjman did not report any relevant financial conflicts of interests.

CHICAGO – Escherichia coli O26 does not appear to cause severe disease in children, according to an epidemiologic study of a recent outbreak in an Oregon child care center.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Shedding in the stool of infected children was prolonged, lasting up to 46 days, but there was no secondary transmission of the pathogen to household members.

Laboratory testing showed that the pathogen produced type 1 Shiga toxin but not type 2 Shiga toxin, which is seen in some other E. coli serotypes and carries a higher risk of hemolytic uremic syndrome.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported

"This study raised more questions than it answered," acknowledged lead investigator Dr. Mathieu Tourdjman, a Centers for Disease Control and Prevention Epidemic Intelligence Service officer with the Oregon Health Authority in Portland. But taken together, the findings generally point to a low-virulence pathogen.

This new information does not warrant any change to Oregon’s policy for child care settings when O26 is detected, according to Dr. Tourdjman. That policy requires that infected children be excluded until they have two consecutive negative stool samples, but allows the local health department to waive the exclusion at its discretion.

"In the context of an O26 Shiga toxin 1–only outbreak in a child care center, we continue to recommend that symptomatic children be excluded at least until symptoms resolve, and that the incidence of infection should be closely monitored," he said. "Routine hand washing before meals and before and after changing diapers and toileting should be emphasized."

And restriction criteria should remain flexible. "In the absence of severe disease, requiring two consecutive negative stool samples to lift the exclusion might not be justifiable," Dr. Tourdjman commented. "And routine testing of asymptomatic children should not be recommended."

Public health officials agree that children with E. coli O157 (the most common serotype) should be excluded from child care until two consecutive negative stool samples are obtained, he noted by way of background. But because of a lack of data, there is no consensus when it comes to restrictions for children with E. coli O26, the second most common serotype.

The Oregon outbreak occurred in October 2010 at a child care center having 76 attendees aged 6 weeks to 12 years, Dr. Tourdjman reported at the conference, which was sponsored by the American Society for Microbiology.

Overall, 61 people – all 13 staff, all 41 attendees in four of five preschool classrooms, and all 7 school-aged siblings of those attendees – provided stool samples for testing.

Results showed that nine of the children and one of the staff were positive for Shiga toxin–producing E. coli O26, as determined by initial polymerase chain reaction for the toxin and confirmed by subsequent stool culture for typing.

Four of the 10 positive individuals, all children, had diarrhea, which was bloody in one case. But none experienced hemolytic uremic syndrome or other serious illness. Laboratory tests showed that all isolates matched and all produced only Shiga toxin type 1.

Of the nine infected children, two had consistently negative test results after their initial positive result. Among the other seven, the median duration of shedding in stool was 25 days, with a maximum of 46 days.

Half of the households of infected children agreed to testing to assess possible secondary transmission, and 14 of 17 household members provided stool samples. None were positive by polymerase chain reaction for Shiga toxin.

In the wake of the outbreak, the child care center was thoroughly cleaned and staff were trained in hygiene practices, according to Dr. Tourdjman. The children with diarrhea were excluded from the center, and the asymptomatic positive children were cohorted (separated from other children in a single classroom).

However, the cohorting was discontinued after 3 weeks given that all factors pointed to a low-virulence pathogen and there was strict compliance with the hygiene practices. "The decision to stop cohorting was not based on the results of the shedding study," he noted. "No symptoms were reported at the center after the discontinuation of cohorting."

Dr. Tourdjman did not report any relevant financial conflicts of interests.

CHICAGO – Escherichia coli O26 does not appear to cause severe disease in children, according to an epidemiologic study of a recent outbreak in an Oregon child care center.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Shedding in the stool of infected children was prolonged, lasting up to 46 days, but there was no secondary transmission of the pathogen to household members.

Laboratory testing showed that the pathogen produced type 1 Shiga toxin but not type 2 Shiga toxin, which is seen in some other E. coli serotypes and carries a higher risk of hemolytic uremic syndrome.

In all, 60% of 10 infected children and staff were asymptomatic, and none developed illness more serious than diarrhea, investigators reported

"This study raised more questions than it answered," acknowledged lead investigator Dr. Mathieu Tourdjman, a Centers for Disease Control and Prevention Epidemic Intelligence Service officer with the Oregon Health Authority in Portland. But taken together, the findings generally point to a low-virulence pathogen.

This new information does not warrant any change to Oregon’s policy for child care settings when O26 is detected, according to Dr. Tourdjman. That policy requires that infected children be excluded until they have two consecutive negative stool samples, but allows the local health department to waive the exclusion at its discretion.

"In the context of an O26 Shiga toxin 1–only outbreak in a child care center, we continue to recommend that symptomatic children be excluded at least until symptoms resolve, and that the incidence of infection should be closely monitored," he said. "Routine hand washing before meals and before and after changing diapers and toileting should be emphasized."

And restriction criteria should remain flexible. "In the absence of severe disease, requiring two consecutive negative stool samples to lift the exclusion might not be justifiable," Dr. Tourdjman commented. "And routine testing of asymptomatic children should not be recommended."

Public health officials agree that children with E. coli O157 (the most common serotype) should be excluded from child care until two consecutive negative stool samples are obtained, he noted by way of background. But because of a lack of data, there is no consensus when it comes to restrictions for children with E. coli O26, the second most common serotype.

The Oregon outbreak occurred in October 2010 at a child care center having 76 attendees aged 6 weeks to 12 years, Dr. Tourdjman reported at the conference, which was sponsored by the American Society for Microbiology.

Overall, 61 people – all 13 staff, all 41 attendees in four of five preschool classrooms, and all 7 school-aged siblings of those attendees – provided stool samples for testing.

Results showed that nine of the children and one of the staff were positive for Shiga toxin–producing E. coli O26, as determined by initial polymerase chain reaction for the toxin and confirmed by subsequent stool culture for typing.

Four of the 10 positive individuals, all children, had diarrhea, which was bloody in one case. But none experienced hemolytic uremic syndrome or other serious illness. Laboratory tests showed that all isolates matched and all produced only Shiga toxin type 1.

Of the nine infected children, two had consistently negative test results after their initial positive result. Among the other seven, the median duration of shedding in stool was 25 days, with a maximum of 46 days.

Half of the households of infected children agreed to testing to assess possible secondary transmission, and 14 of 17 household members provided stool samples. None were positive by polymerase chain reaction for Shiga toxin.

In the wake of the outbreak, the child care center was thoroughly cleaned and staff were trained in hygiene practices, according to Dr. Tourdjman. The children with diarrhea were excluded from the center, and the asymptomatic positive children were cohorted (separated from other children in a single classroom).

However, the cohorting was discontinued after 3 weeks given that all factors pointed to a low-virulence pathogen and there was strict compliance with the hygiene practices. "The decision to stop cohorting was not based on the results of the shedding study," he noted. "No symptoms were reported at the center after the discontinuation of cohorting."

Dr. Tourdjman did not report any relevant financial conflicts of interests.

CHICAGO – If you think the privacy curtains at your health care facility are free of potentially harmful bacteria, think again.

Within one week of being laundered, 92% of hospital curtains were contaminated with pathogens that included methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) species, results from a single-center study showed.

"Usually when health care workers walk into a patient room, they’ll wash their hands, grab the curtain, pull it aside, and then touch the patient, without realizing that they touched the curtain," Marin L. Schweizer, Ph.D., said in an interview during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "The message here is that health care workers should wash their hands after touching privacy curtains and before touching the patient."

Over a period of 3 weeks, Dr. Schweizer and her associates obtained 180 swab cultures from 43 privacy curtains in 30 rooms at the University of Iowa Hospitals and Clinics (8 medical intensive care units, 7 surgical ICUs, and 15 medical wards). They obtained the cultures twice weekly from an 800-cm² area on the leading edge of each curtain, and marked each curtain to determine when it was changed.

Standard microbiologic methods, including broth enrichment, were used to determine contamination. To distinguish persistence of pathogens on curtains from recontamination, all MRSA and VRE were typed using pulsed-field gel electrophoresis.

Of the 13 curtains placed during the study, 12 (92%) demonstrated contamination within 1 week, while 41 of the 45 curtains (95%) demonstrated contamination on at least one occasion. "We thought the prevalence would be high, but we didn’t think it would be that high," commented Dr. Schweizer of the department of general internal medicine at the University of Iowa, Iowa City.

She went on to report that VRE and MRSA were isolated from 42% and 21% of the curtains, respectively. Eight curtains were contaminated with VRE at more than one time point: three with persistence of a single genetic type and five with genetic types over time. "This shows that there are lots of pathogens on the curtains," Dr. Schweizer said. "They stick around for a long time and they’re constantly being recontaminated."

Two-thirds of all swab cultures (66%) were positive for either S. aureus, Enterococcus spp. (44%), or gram-negative rods (22%).

The study was funded by PurThread, a manufacturer of antimicrobial fabrics for use in health care settings. One of the study investigators, Dr. Eli Perenchevich, is a paid consultant for PurThread.

According to Dr. Schweizer, none of the curtains studied were made by PurThread.

CHICAGO – If you think the privacy curtains at your health care facility are free of potentially harmful bacteria, think again.

Within one week of being laundered, 92% of hospital curtains were contaminated with pathogens that included methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) species, results from a single-center study showed.

"Usually when health care workers walk into a patient room, they’ll wash their hands, grab the curtain, pull it aside, and then touch the patient, without realizing that they touched the curtain," Marin L. Schweizer, Ph.D., said in an interview during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "The message here is that health care workers should wash their hands after touching privacy curtains and before touching the patient."

Over a period of 3 weeks, Dr. Schweizer and her associates obtained 180 swab cultures from 43 privacy curtains in 30 rooms at the University of Iowa Hospitals and Clinics (8 medical intensive care units, 7 surgical ICUs, and 15 medical wards). They obtained the cultures twice weekly from an 800-cm² area on the leading edge of each curtain, and marked each curtain to determine when it was changed.

Standard microbiologic methods, including broth enrichment, were used to determine contamination. To distinguish persistence of pathogens on curtains from recontamination, all MRSA and VRE were typed using pulsed-field gel electrophoresis.

Of the 13 curtains placed during the study, 12 (92%) demonstrated contamination within 1 week, while 41 of the 45 curtains (95%) demonstrated contamination on at least one occasion. "We thought the prevalence would be high, but we didn’t think it would be that high," commented Dr. Schweizer of the department of general internal medicine at the University of Iowa, Iowa City.

She went on to report that VRE and MRSA were isolated from 42% and 21% of the curtains, respectively. Eight curtains were contaminated with VRE at more than one time point: three with persistence of a single genetic type and five with genetic types over time. "This shows that there are lots of pathogens on the curtains," Dr. Schweizer said. "They stick around for a long time and they’re constantly being recontaminated."

Two-thirds of all swab cultures (66%) were positive for either S. aureus, Enterococcus spp. (44%), or gram-negative rods (22%).

The study was funded by PurThread, a manufacturer of antimicrobial fabrics for use in health care settings. One of the study investigators, Dr. Eli Perenchevich, is a paid consultant for PurThread.

According to Dr. Schweizer, none of the curtains studied were made by PurThread.

CHICAGO – If you think the privacy curtains at your health care facility are free of potentially harmful bacteria, think again.

Within one week of being laundered, 92% of hospital curtains were contaminated with pathogens that included methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) species, results from a single-center study showed.

"Usually when health care workers walk into a patient room, they’ll wash their hands, grab the curtain, pull it aside, and then touch the patient, without realizing that they touched the curtain," Marin L. Schweizer, Ph.D., said in an interview during a poster session at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy. "The message here is that health care workers should wash their hands after touching privacy curtains and before touching the patient."

Over a period of 3 weeks, Dr. Schweizer and her associates obtained 180 swab cultures from 43 privacy curtains in 30 rooms at the University of Iowa Hospitals and Clinics (8 medical intensive care units, 7 surgical ICUs, and 15 medical wards). They obtained the cultures twice weekly from an 800-cm² area on the leading edge of each curtain, and marked each curtain to determine when it was changed.

Standard microbiologic methods, including broth enrichment, were used to determine contamination. To distinguish persistence of pathogens on curtains from recontamination, all MRSA and VRE were typed using pulsed-field gel electrophoresis.

Of the 13 curtains placed during the study, 12 (92%) demonstrated contamination within 1 week, while 41 of the 45 curtains (95%) demonstrated contamination on at least one occasion. "We thought the prevalence would be high, but we didn’t think it would be that high," commented Dr. Schweizer of the department of general internal medicine at the University of Iowa, Iowa City.

She went on to report that VRE and MRSA were isolated from 42% and 21% of the curtains, respectively. Eight curtains were contaminated with VRE at more than one time point: three with persistence of a single genetic type and five with genetic types over time. "This shows that there are lots of pathogens on the curtains," Dr. Schweizer said. "They stick around for a long time and they’re constantly being recontaminated."

Two-thirds of all swab cultures (66%) were positive for either S. aureus, Enterococcus spp. (44%), or gram-negative rods (22%).

The study was funded by PurThread, a manufacturer of antimicrobial fabrics for use in health care settings. One of the study investigators, Dr. Eli Perenchevich, is a paid consultant for PurThread.

According to Dr. Schweizer, none of the curtains studied were made by PurThread.

CHICAGO – The rate of skin and soft tissue infections in Americans younger than 65 years old increased by approximately 11% between 2005 and 2008, a study has shown.

Using national projections of incidence and costs from a population of commercially insured individuals, the study indicated "that more than 11 million skin and soft tissue infections occur annually in Americans younger than 65 years old, with an annual associated medical cost of almost $24 billion," Dr. Loren G. Miller reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Although incidence data from the early 2000s linked the emergence of community-associated methicillin-resistant Staphylococcus aureus with a dramatic increase in skin and soft tissue infections [SSTIs], "more recent data on the [SSTI] incidence rates and treatment costs are lacking," Dr. Miller said in a poster presentation.

To estimate updated SSTI incidence rates and the related health care utilization costs, he and his colleagues examined ambulatory and inpatient data from 2005 to 2008 for approximately 24 million Americans between 0 and 64 years using the HealthCore Integrated Research Database, a longitudinal health care claims database.

The investigators extracted data for SSTI diagnoses based on ICD-9 codes and estimated the annual SSTI incidence by diagnosis setting and age group. They also estimated complication rates by SSTI type, the direct medical costs associated with SSTI claims, and national projections of SSTI cases, explained Dr. Miller, director of the infection care program at Harbor-UCLA Medical Center in Torrance, Calif.

From the 2005 to 2008 data, "we identified more than 1.5 million [SSTIs], 95% of which were diagnosed in the ambulatory setting," he said. Of the 1,506,882 SSTIs identified, 60% were classified as abscesses or cellulitis.

During the 4-year period of investigation, the incidence of SSTIs increased from 41.0/1,000 person-years to 45.5/1,000, with the highest incidence of both ambulatory onset and inpatient onset observed in those aged 45-64 years. In this age group the incidence of SSTI was 42.26/1,000 person-years with ambulatory onset and 3.39 with inpatient onset.

A total of 1.2% of the ambulatory group and 24.1% of the inpatient group developed at least one SSTI complication, including myositis, osteomyelitis, gangrene, and sepsis. In addition, 1.48% of the ambulatory group and 9.8% of the inpatient group required subsequent hospitalization for SSTI-related complications.

"The complication rates depended on the type of infection and the setting of the initial diagnosis," he said. In both the ambulatory-onset and inpatient-onset groups, decubitus ulcers and nonhealing surgical wounds were associated with the highest complication rates.

Based on the acquired data, the 2010 projected annual cost associated with SSTIs in the United States in this population was approximately $24 billion, an amount comparable to the overall U.S. hospital costs associated with back pain, cardiac dysrhythmias, or acute cerebrovascular disease. The mean direct medical cost associated with an initial SSTI was $2,107, and the median cost was $249.

The generalizability of the findings is limited by the study design, specifically the lack of data for individuals older than 64 years and those without insurance, the absence of data on the microbiologic etiology of the SSTIs, and the fact that the accuracy of ICD-9 SSTI diagnoses are not well validated. Still, the estimated incidence of 4 SSTIs per 100 person-years in this population and the high associated health care costs suggest that targeted interventions to prevent SSTIs "could reduce morbidity and health care resource utilization substantially," Dr. Miller concluded.

Dr. Miller disclosed financial relationships with GlaxoSmithKline, Cubist, and Pfizer. GlaxoSmithKline provided funding for this study.

CHICAGO – The rate of skin and soft tissue infections in Americans younger than 65 years old increased by approximately 11% between 2005 and 2008, a study has shown.

Using national projections of incidence and costs from a population of commercially insured individuals, the study indicated "that more than 11 million skin and soft tissue infections occur annually in Americans younger than 65 years old, with an annual associated medical cost of almost $24 billion," Dr. Loren G. Miller reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Although incidence data from the early 2000s linked the emergence of community-associated methicillin-resistant Staphylococcus aureus with a dramatic increase in skin and soft tissue infections [SSTIs], "more recent data on the [SSTI] incidence rates and treatment costs are lacking," Dr. Miller said in a poster presentation.

To estimate updated SSTI incidence rates and the related health care utilization costs, he and his colleagues examined ambulatory and inpatient data from 2005 to 2008 for approximately 24 million Americans between 0 and 64 years using the HealthCore Integrated Research Database, a longitudinal health care claims database.

The investigators extracted data for SSTI diagnoses based on ICD-9 codes and estimated the annual SSTI incidence by diagnosis setting and age group. They also estimated complication rates by SSTI type, the direct medical costs associated with SSTI claims, and national projections of SSTI cases, explained Dr. Miller, director of the infection care program at Harbor-UCLA Medical Center in Torrance, Calif.

From the 2005 to 2008 data, "we identified more than 1.5 million [SSTIs], 95% of which were diagnosed in the ambulatory setting," he said. Of the 1,506,882 SSTIs identified, 60% were classified as abscesses or cellulitis.

During the 4-year period of investigation, the incidence of SSTIs increased from 41.0/1,000 person-years to 45.5/1,000, with the highest incidence of both ambulatory onset and inpatient onset observed in those aged 45-64 years. In this age group the incidence of SSTI was 42.26/1,000 person-years with ambulatory onset and 3.39 with inpatient onset.

A total of 1.2% of the ambulatory group and 24.1% of the inpatient group developed at least one SSTI complication, including myositis, osteomyelitis, gangrene, and sepsis. In addition, 1.48% of the ambulatory group and 9.8% of the inpatient group required subsequent hospitalization for SSTI-related complications.

"The complication rates depended on the type of infection and the setting of the initial diagnosis," he said. In both the ambulatory-onset and inpatient-onset groups, decubitus ulcers and nonhealing surgical wounds were associated with the highest complication rates.

Based on the acquired data, the 2010 projected annual cost associated with SSTIs in the United States in this population was approximately $24 billion, an amount comparable to the overall U.S. hospital costs associated with back pain, cardiac dysrhythmias, or acute cerebrovascular disease. The mean direct medical cost associated with an initial SSTI was $2,107, and the median cost was $249.

The generalizability of the findings is limited by the study design, specifically the lack of data for individuals older than 64 years and those without insurance, the absence of data on the microbiologic etiology of the SSTIs, and the fact that the accuracy of ICD-9 SSTI diagnoses are not well validated. Still, the estimated incidence of 4 SSTIs per 100 person-years in this population and the high associated health care costs suggest that targeted interventions to prevent SSTIs "could reduce morbidity and health care resource utilization substantially," Dr. Miller concluded.

Dr. Miller disclosed financial relationships with GlaxoSmithKline, Cubist, and Pfizer. GlaxoSmithKline provided funding for this study.

CHICAGO – The rate of skin and soft tissue infections in Americans younger than 65 years old increased by approximately 11% between 2005 and 2008, a study has shown.

Using national projections of incidence and costs from a population of commercially insured individuals, the study indicated "that more than 11 million skin and soft tissue infections occur annually in Americans younger than 65 years old, with an annual associated medical cost of almost $24 billion," Dr. Loren G. Miller reported at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.

Although incidence data from the early 2000s linked the emergence of community-associated methicillin-resistant Staphylococcus aureus with a dramatic increase in skin and soft tissue infections [SSTIs], "more recent data on the [SSTI] incidence rates and treatment costs are lacking," Dr. Miller said in a poster presentation.

To estimate updated SSTI incidence rates and the related health care utilization costs, he and his colleagues examined ambulatory and inpatient data from 2005 to 2008 for approximately 24 million Americans between 0 and 64 years using the HealthCore Integrated Research Database, a longitudinal health care claims database.

The investigators extracted data for SSTI diagnoses based on ICD-9 codes and estimated the annual SSTI incidence by diagnosis setting and age group. They also estimated complication rates by SSTI type, the direct medical costs associated with SSTI claims, and national projections of SSTI cases, explained Dr. Miller, director of the infection care program at Harbor-UCLA Medical Center in Torrance, Calif.

From the 2005 to 2008 data, "we identified more than 1.5 million [SSTIs], 95% of which were diagnosed in the ambulatory setting," he said. Of the 1,506,882 SSTIs identified, 60% were classified as abscesses or cellulitis.

During the 4-year period of investigation, the incidence of SSTIs increased from 41.0/1,000 person-years to 45.5/1,000, with the highest incidence of both ambulatory onset and inpatient onset observed in those aged 45-64 years. In this age group the incidence of SSTI was 42.26/1,000 person-years with ambulatory onset and 3.39 with inpatient onset.

A total of 1.2% of the ambulatory group and 24.1% of the inpatient group developed at least one SSTI complication, including myositis, osteomyelitis, gangrene, and sepsis. In addition, 1.48% of the ambulatory group and 9.8% of the inpatient group required subsequent hospitalization for SSTI-related complications.

"The complication rates depended on the type of infection and the setting of the initial diagnosis," he said. In both the ambulatory-onset and inpatient-onset groups, decubitus ulcers and nonhealing surgical wounds were associated with the highest complication rates.

Based on the acquired data, the 2010 projected annual cost associated with SSTIs in the United States in this population was approximately $24 billion, an amount comparable to the overall U.S. hospital costs associated with back pain, cardiac dysrhythmias, or acute cerebrovascular disease. The mean direct medical cost associated with an initial SSTI was $2,107, and the median cost was $249.

The generalizability of the findings is limited by the study design, specifically the lack of data for individuals older than 64 years and those without insurance, the absence of data on the microbiologic etiology of the SSTIs, and the fact that the accuracy of ICD-9 SSTI diagnoses are not well validated. Still, the estimated incidence of 4 SSTIs per 100 person-years in this population and the high associated health care costs suggest that targeted interventions to prevent SSTIs "could reduce morbidity and health care resource utilization substantially," Dr. Miller concluded.

Dr. Miller disclosed financial relationships with GlaxoSmithKline, Cubist, and Pfizer. GlaxoSmithKline provided funding for this study.