Roula Baroudi, MD

A 50-year-old white woman who worked in a nail salon and had a history of Crohn disease (asymptomatic, off treatment for several years) presented to her primary care physician with right breast erythema and pain for the previous 3 days. The symptoms started as a red streak in the upper half of the breast with no reported history of a recent trauma to the breast and no history of prior surgeries. The patient reported having no nipple discharge or any associated constitutional symptoms.

On initial examination, the patient was found to have intact skin with 3 cm of localized redness. She was diagnosed with right breast mastitis and given oral erythromycin due to a history of allergy to penicillin. Four days later, while she was still taking oral antibiotics, her symptoms worsened. She was referred to the breast clinic and reevaluated by the breast surgeon, who reported findings of right breast tenderness and induration localized to the upper inner quadrant with no signs of fluctuation to suggest an abscess. A breast ultrasound showed inflammatory changes of the right breast around the perinipple-areola complex area. Fine-needle aspiration (FNA) was performed in the surgery clinic. Additional laboratory tests revealed no leukocytosis on routine blood work. She was hospitalized and received IV vancomycin and clindamycin. Clindamycin was given to cover anaerobes along with vancomycin, which is more reliable to cover staphylococcus, including methicillin-resistant Staphylococcus aureus empirically. The bacterial culture showed no growth, and the reported findings of the FNA were consistent with inflammatory process without evidence of malignancy. The erythema improved in a few days, and the patient was discharged home on oral linezolid, as she declined further IV antibiotics.

At the follow-up surgical clinic visit, the induration was the same, and the erythema had progressed to involve a larger area of the breast. Repeat ultrasound showed an edematous area within the retro-areolar region. Repeat FNA was performed in the clinic, and 3 mL of bloody fluid was obtained. The bacterial culture again showed no growth, and the cytologic findings revealed an inflammatory process with more exudates but no evidence of malignancy. Due to lack of expected clinical improvement with the treatment for presumptive acute bacterial infection, the decision was made to proceed with excisional biopsy to rule out malignances and other potential etiologies of an infectious/inflammatory process.

Excision of the involved area, consisting of inner upper quadrantectomy and terminal duct excision, was performed due to the operative findings of inflamed, necrotic tissue and the presence of multiple abscesses. The pathology report confirmed the presence of microabscesses and mastitis with periductal inflammation. Microbiology data revealed a negative bacterial culture and negative acid-fast bacilli (AFB) smear. However, the AFB culture from MB/BacT (a liquid media by BioMérieux, Marcy-l’Étoile, France) grew an atypical mycobacterium.

An infectious disease consultation was requested for further guidance. The AFB isolate was sent to the University of Texas Health Science Center, where the atypical mycobacterium was later identified as Mycobacteriumchelonae-abscessus complex. This was determined to be the Mycobacterium abscessus species. The susceptibility test report revealed the organism was sensitive to amikacin, cefoxitin, clarithromycin, and linezolid and demonstrated intermediate sensitivity to quinolones. The organism was resistant to doxycycline and sulfamethoxazole.

During evaluation in the infectious disease clinic, the patient reported night sweats. The examination of her right breast revealed a well-healed surgical scar with surrounding erythema and induration. Blood cultures for AFB taken later were negative. The patient was married with no risk factors for HIV but consented to a test, which also was negative.The patient was started on oral clarithromycin and ciprofloxacin, pending the sensitivity of the mycobacterium.

Due to the slow clinical improvement on oral antibiotics after surgery, intolerance to ciprofloxacin (severe nausea), and the sensitivity pattern, the decision was made to add IV cefoxitin (minimum inhibitory concentration [MIC] < 64) and continue with oral clarithromycin (MIC < 0.1).

During her 2-week follow-up visit, the patient reported significant improvement in pain, swelling, and induration of her breast, confirmed by physical examination. At the 12-week follow-up visit, the patient’s erythema and induration had resolved completely. The IV cefoxitin was discontinued, and her oral clarithromycin was renewed for another 3 months. The decision to treat with antibiotics after surgical removal of necrotic tissue was based on previous cases and the need to ensure complete eradication of the infection prior to breast reconstruction.

The patient remained asymptomatic at her 6-month follow-up visit after completion of the antibiotics course. No recurrence of the atypical mycobacterium infection was detected. A year later, she underwent reconstruction of her right breast.

Discussion

Mycobacterium abscessus is a human pathogen commonly found in the soil, water, or sewerage. The organism is a nontuberculous mycobacterium characterized by rapid growth and a lack of pigmentation on the gram-positive rods. A review of the literature revealed multiple cases of M abscessus infection of the skin, but only one reference was made concerning breast tissues in which rapidly growing M abscessus initially was misdiagnosed as fibrocystic disease. Yasar and colleagues reported a woman with a history of fibrocystic breast disease who presented with a breast abscess later identified as M abscessus.¹ She was treated with amikacin, linezolid, and clarithromycin. The authors concluded that antimycobacterial therapy for M abscessus infection remains poorly established, and surgical therapy is often required in treating this atypical mycobacterium infection.

Two previous reports have referred to M abscessus infection in the breast tissue; however, this current case is unique. The authors believe this case study to be noteworthy in its description of an acute presentation in a woman with neither trauma nor history of breast disease, such as fibrocystic breasts. This unusual presentation makes the diagnosis of M abscessus infection more difficult to diagnose and treat in a timely manner.

Reports of M abscessus infection have been documented in skin and soft tissues. These cases involved prior trauma to the skin, such as acupuncture, filler injections, surgical procedures, or other traumatic events. Painful nodules and plaque formation also were reported with a culture showing polymorphonuclear microabscesses and granulomatous inflammation in the dermis and subcutaneous fat tissue, identified as M abscessus.^2,3

Another study reported a case of M abscessus infection after a patient had a tattoo.⁴ Possible of infections from tattoos may be localized or systemic. Because more people are being tattooed and developing skin infections resistant to standard antibiotic treatment, M abscessus infection must be considered in the differential diagnosis of these infections.

Conclusion

Mycobacterium abscessus infection is usually seen in immunocompromised hosts or those with trauma. However, as more cases of M abscessus are seen in skin and soft-tissue infections because of more cosmetic injections, body art, or minor surgical procedures, clinicians must have a high degree of suspicion for this pathogen, especially if the patient does not respond to standard antibacterial therapy. Although amikacin and clarithromycin are 2 antimicrobial agents that have shown effectiveness against this pathogen, obtaining a skin biopsy along with mycobacterial culture and sensitivity testing is determining the proper agents for successful treatment. The importance of early recognition and proper antibiotic therapy is crucial to avoid delay in diagnosis and to decrease potential tissue loss.

A 50-year-old white woman who worked in a nail salon and had a history of Crohn disease (asymptomatic, off treatment for several years) presented to her primary care physician with right breast erythema and pain for the previous 3 days. The symptoms started as a red streak in the upper half of the breast with no reported history of a recent trauma to the breast and no history of prior surgeries. The patient reported having no nipple discharge or any associated constitutional symptoms.

On initial examination, the patient was found to have intact skin with 3 cm of localized redness. She was diagnosed with right breast mastitis and given oral erythromycin due to a history of allergy to penicillin. Four days later, while she was still taking oral antibiotics, her symptoms worsened. She was referred to the breast clinic and reevaluated by the breast surgeon, who reported findings of right breast tenderness and induration localized to the upper inner quadrant with no signs of fluctuation to suggest an abscess. A breast ultrasound showed inflammatory changes of the right breast around the perinipple-areola complex area. Fine-needle aspiration (FNA) was performed in the surgery clinic. Additional laboratory tests revealed no leukocytosis on routine blood work. She was hospitalized and received IV vancomycin and clindamycin. Clindamycin was given to cover anaerobes along with vancomycin, which is more reliable to cover staphylococcus, including methicillin-resistant Staphylococcus aureus empirically. The bacterial culture showed no growth, and the reported findings of the FNA were consistent with inflammatory process without evidence of malignancy. The erythema improved in a few days, and the patient was discharged home on oral linezolid, as she declined further IV antibiotics.

At the follow-up surgical clinic visit, the induration was the same, and the erythema had progressed to involve a larger area of the breast. Repeat ultrasound showed an edematous area within the retro-areolar region. Repeat FNA was performed in the clinic, and 3 mL of bloody fluid was obtained. The bacterial culture again showed no growth, and the cytologic findings revealed an inflammatory process with more exudates but no evidence of malignancy. Due to lack of expected clinical improvement with the treatment for presumptive acute bacterial infection, the decision was made to proceed with excisional biopsy to rule out malignances and other potential etiologies of an infectious/inflammatory process.

Excision of the involved area, consisting of inner upper quadrantectomy and terminal duct excision, was performed due to the operative findings of inflamed, necrotic tissue and the presence of multiple abscesses. The pathology report confirmed the presence of microabscesses and mastitis with periductal inflammation. Microbiology data revealed a negative bacterial culture and negative acid-fast bacilli (AFB) smear. However, the AFB culture from MB/BacT (a liquid media by BioMérieux, Marcy-l’Étoile, France) grew an atypical mycobacterium.

An infectious disease consultation was requested for further guidance. The AFB isolate was sent to the University of Texas Health Science Center, where the atypical mycobacterium was later identified as Mycobacteriumchelonae-abscessus complex. This was determined to be the Mycobacterium abscessus species. The susceptibility test report revealed the organism was sensitive to amikacin, cefoxitin, clarithromycin, and linezolid and demonstrated intermediate sensitivity to quinolones. The organism was resistant to doxycycline and sulfamethoxazole.

During evaluation in the infectious disease clinic, the patient reported night sweats. The examination of her right breast revealed a well-healed surgical scar with surrounding erythema and induration. Blood cultures for AFB taken later were negative. The patient was married with no risk factors for HIV but consented to a test, which also was negative.The patient was started on oral clarithromycin and ciprofloxacin, pending the sensitivity of the mycobacterium.

Due to the slow clinical improvement on oral antibiotics after surgery, intolerance to ciprofloxacin (severe nausea), and the sensitivity pattern, the decision was made to add IV cefoxitin (minimum inhibitory concentration [MIC] < 64) and continue with oral clarithromycin (MIC < 0.1).

During her 2-week follow-up visit, the patient reported significant improvement in pain, swelling, and induration of her breast, confirmed by physical examination. At the 12-week follow-up visit, the patient’s erythema and induration had resolved completely. The IV cefoxitin was discontinued, and her oral clarithromycin was renewed for another 3 months. The decision to treat with antibiotics after surgical removal of necrotic tissue was based on previous cases and the need to ensure complete eradication of the infection prior to breast reconstruction.

The patient remained asymptomatic at her 6-month follow-up visit after completion of the antibiotics course. No recurrence of the atypical mycobacterium infection was detected. A year later, she underwent reconstruction of her right breast.

Discussion

Mycobacterium abscessus is a human pathogen commonly found in the soil, water, or sewerage. The organism is a nontuberculous mycobacterium characterized by rapid growth and a lack of pigmentation on the gram-positive rods. A review of the literature revealed multiple cases of M abscessus infection of the skin, but only one reference was made concerning breast tissues in which rapidly growing M abscessus initially was misdiagnosed as fibrocystic disease. Yasar and colleagues reported a woman with a history of fibrocystic breast disease who presented with a breast abscess later identified as M abscessus.¹ She was treated with amikacin, linezolid, and clarithromycin. The authors concluded that antimycobacterial therapy for M abscessus infection remains poorly established, and surgical therapy is often required in treating this atypical mycobacterium infection.

Two previous reports have referred to M abscessus infection in the breast tissue; however, this current case is unique. The authors believe this case study to be noteworthy in its description of an acute presentation in a woman with neither trauma nor history of breast disease, such as fibrocystic breasts. This unusual presentation makes the diagnosis of M abscessus infection more difficult to diagnose and treat in a timely manner.

Reports of M abscessus infection have been documented in skin and soft tissues. These cases involved prior trauma to the skin, such as acupuncture, filler injections, surgical procedures, or other traumatic events. Painful nodules and plaque formation also were reported with a culture showing polymorphonuclear microabscesses and granulomatous inflammation in the dermis and subcutaneous fat tissue, identified as M abscessus.^2,3

Another study reported a case of M abscessus infection after a patient had a tattoo.⁴ Possible of infections from tattoos may be localized or systemic. Because more people are being tattooed and developing skin infections resistant to standard antibiotic treatment, M abscessus infection must be considered in the differential diagnosis of these infections.

Conclusion

Mycobacterium abscessus infection is usually seen in immunocompromised hosts or those with trauma. However, as more cases of M abscessus are seen in skin and soft-tissue infections because of more cosmetic injections, body art, or minor surgical procedures, clinicians must have a high degree of suspicion for this pathogen, especially if the patient does not respond to standard antibacterial therapy. Although amikacin and clarithromycin are 2 antimicrobial agents that have shown effectiveness against this pathogen, obtaining a skin biopsy along with mycobacterial culture and sensitivity testing is determining the proper agents for successful treatment. The importance of early recognition and proper antibiotic therapy is crucial to avoid delay in diagnosis and to decrease potential tissue loss.

A 50-year-old white woman who worked in a nail salon and had a history of Crohn disease (asymptomatic, off treatment for several years) presented to her primary care physician with right breast erythema and pain for the previous 3 days. The symptoms started as a red streak in the upper half of the breast with no reported history of a recent trauma to the breast and no history of prior surgeries. The patient reported having no nipple discharge or any associated constitutional symptoms.

On initial examination, the patient was found to have intact skin with 3 cm of localized redness. She was diagnosed with right breast mastitis and given oral erythromycin due to a history of allergy to penicillin. Four days later, while she was still taking oral antibiotics, her symptoms worsened. She was referred to the breast clinic and reevaluated by the breast surgeon, who reported findings of right breast tenderness and induration localized to the upper inner quadrant with no signs of fluctuation to suggest an abscess. A breast ultrasound showed inflammatory changes of the right breast around the perinipple-areola complex area. Fine-needle aspiration (FNA) was performed in the surgery clinic. Additional laboratory tests revealed no leukocytosis on routine blood work. She was hospitalized and received IV vancomycin and clindamycin. Clindamycin was given to cover anaerobes along with vancomycin, which is more reliable to cover staphylococcus, including methicillin-resistant Staphylococcus aureus empirically. The bacterial culture showed no growth, and the reported findings of the FNA were consistent with inflammatory process without evidence of malignancy. The erythema improved in a few days, and the patient was discharged home on oral linezolid, as she declined further IV antibiotics.

At the follow-up surgical clinic visit, the induration was the same, and the erythema had progressed to involve a larger area of the breast. Repeat ultrasound showed an edematous area within the retro-areolar region. Repeat FNA was performed in the clinic, and 3 mL of bloody fluid was obtained. The bacterial culture again showed no growth, and the cytologic findings revealed an inflammatory process with more exudates but no evidence of malignancy. Due to lack of expected clinical improvement with the treatment for presumptive acute bacterial infection, the decision was made to proceed with excisional biopsy to rule out malignances and other potential etiologies of an infectious/inflammatory process.

Excision of the involved area, consisting of inner upper quadrantectomy and terminal duct excision, was performed due to the operative findings of inflamed, necrotic tissue and the presence of multiple abscesses. The pathology report confirmed the presence of microabscesses and mastitis with periductal inflammation. Microbiology data revealed a negative bacterial culture and negative acid-fast bacilli (AFB) smear. However, the AFB culture from MB/BacT (a liquid media by BioMérieux, Marcy-l’Étoile, France) grew an atypical mycobacterium.

An infectious disease consultation was requested for further guidance. The AFB isolate was sent to the University of Texas Health Science Center, where the atypical mycobacterium was later identified as Mycobacteriumchelonae-abscessus complex. This was determined to be the Mycobacterium abscessus species. The susceptibility test report revealed the organism was sensitive to amikacin, cefoxitin, clarithromycin, and linezolid and demonstrated intermediate sensitivity to quinolones. The organism was resistant to doxycycline and sulfamethoxazole.

During evaluation in the infectious disease clinic, the patient reported night sweats. The examination of her right breast revealed a well-healed surgical scar with surrounding erythema and induration. Blood cultures for AFB taken later were negative. The patient was married with no risk factors for HIV but consented to a test, which also was negative.The patient was started on oral clarithromycin and ciprofloxacin, pending the sensitivity of the mycobacterium.

Due to the slow clinical improvement on oral antibiotics after surgery, intolerance to ciprofloxacin (severe nausea), and the sensitivity pattern, the decision was made to add IV cefoxitin (minimum inhibitory concentration [MIC] < 64) and continue with oral clarithromycin (MIC < 0.1).

During her 2-week follow-up visit, the patient reported significant improvement in pain, swelling, and induration of her breast, confirmed by physical examination. At the 12-week follow-up visit, the patient’s erythema and induration had resolved completely. The IV cefoxitin was discontinued, and her oral clarithromycin was renewed for another 3 months. The decision to treat with antibiotics after surgical removal of necrotic tissue was based on previous cases and the need to ensure complete eradication of the infection prior to breast reconstruction.

The patient remained asymptomatic at her 6-month follow-up visit after completion of the antibiotics course. No recurrence of the atypical mycobacterium infection was detected. A year later, she underwent reconstruction of her right breast.

Discussion

Mycobacterium abscessus is a human pathogen commonly found in the soil, water, or sewerage. The organism is a nontuberculous mycobacterium characterized by rapid growth and a lack of pigmentation on the gram-positive rods. A review of the literature revealed multiple cases of M abscessus infection of the skin, but only one reference was made concerning breast tissues in which rapidly growing M abscessus initially was misdiagnosed as fibrocystic disease. Yasar and colleagues reported a woman with a history of fibrocystic breast disease who presented with a breast abscess later identified as M abscessus.¹ She was treated with amikacin, linezolid, and clarithromycin. The authors concluded that antimycobacterial therapy for M abscessus infection remains poorly established, and surgical therapy is often required in treating this atypical mycobacterium infection.

Two previous reports have referred to M abscessus infection in the breast tissue; however, this current case is unique. The authors believe this case study to be noteworthy in its description of an acute presentation in a woman with neither trauma nor history of breast disease, such as fibrocystic breasts. This unusual presentation makes the diagnosis of M abscessus infection more difficult to diagnose and treat in a timely manner.

Reports of M abscessus infection have been documented in skin and soft tissues. These cases involved prior trauma to the skin, such as acupuncture, filler injections, surgical procedures, or other traumatic events. Painful nodules and plaque formation also were reported with a culture showing polymorphonuclear microabscesses and granulomatous inflammation in the dermis and subcutaneous fat tissue, identified as M abscessus.^2,3

Another study reported a case of M abscessus infection after a patient had a tattoo.⁴ Possible of infections from tattoos may be localized or systemic. Because more people are being tattooed and developing skin infections resistant to standard antibiotic treatment, M abscessus infection must be considered in the differential diagnosis of these infections.

Conclusion

Mycobacterium abscessus infection is usually seen in immunocompromised hosts or those with trauma. However, as more cases of M abscessus are seen in skin and soft-tissue infections because of more cosmetic injections, body art, or minor surgical procedures, clinicians must have a high degree of suspicion for this pathogen, especially if the patient does not respond to standard antibacterial therapy. Although amikacin and clarithromycin are 2 antimicrobial agents that have shown effectiveness against this pathogen, obtaining a skin biopsy along with mycobacterial culture and sensitivity testing is determining the proper agents for successful treatment. The importance of early recognition and proper antibiotic therapy is crucial to avoid delay in diagnosis and to decrease potential tissue loss.

An antimicrobial stewardship program (ASP) is designed to provide guidance for the safe andcost-effective use of antimicrobial agents. This evidence-based approach addresses the correct selection of antimicrobial agents, dosages, routes of administration, and duration of therapy. In other words, the ASP necessitates the right drug, the right time, the right amount, and the right duration.¹ The ASP reduces the development of multidrug-resistant organisms (MDROs), adverse drug events (such as antibiotic-associated diarrhea and renal toxicity), hospital length of stay, collateral damage (development of Clostridium difficile colitis), and health care costs. Review of the literature has shown the ASP reduces hospital stays among patients with acute bacterial-skin and skin-structure infections along with other costly infections.² 

The ASP is not a new concept, but it is a hot topic. A successful ASP cannot be achieved without the support of the hospital leadership to determine and provide the needed resources. Its success stems from being a joint collaborative effort between pharmacy, medicine, infection control (IC), microbiology, and information technology. The purpose of the ASP is to ensure proper use of antimicrobials within the health care system through the development of a formal, interdisciplinary team. The primary goal of the ASP is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance. 

In today’s world, health care clinicians are dealing with a global challenge of MDROs such as Enterococcus faecium, Staphylococcus aureus (S aureus), Klebsiella pneumonia, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE), better known as “bugs without borders.”³ According to the CDC, antibiotic-resistant infections affect at least 2 million people in the U.S. annually and result in > 23,000 deaths.² According to Thomas Frieden, director of the CDC, the pipeline of new antibiotics is nearly empty for the short term, and new drugs could be a decade away from discovery and approval by the FDA.²

Literature Review

Pasquale and colleagues conducted a retrospective, observational chart review on 62 patients who were admitted for bacterial-skin and skin-structure infections (S aureus, MRSA, MSSA, and Pseudomonas aeruginosa).⁴ The data examined patient demographic characteristics, comorbidities, specific type of skin infection (the most common being cellulitis, major or deep abscesses, and surgical site infections), microbiology, surgical interventions, and recommendations obtained from the ASP committee.

The primary goal of the antimicrobial stewardship program is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance.The ASP recommendations were divided into 5 categories, including dosage changes, de-escalation, antibiotic regimen changes, infectious disease (ID) consults, and other (not described). The ASP offered 85 recommendations, and acceptance of the ASP recommendations by physicians was 95%. The intervention group had a significantly lower length of stay (4.4 days vs 6.2 days, P < .001); and the 30-day all-cause readmission rate was also significantly lower (6.5% vs 16.71%, P = .05). However, the skin and skin-related structures readmission rate did not differ significantly (3.33% vs 6.27%). It was impossible for the investigators to determine exact differences in the amount of antimicrobials used in the intervention group vs the historical controls, because the historical data were based on ICD-9 codes, which may explain the nonsignificant finding.⁴

D’Agata reviewed the antimicrobial usage and ASP programs in dialysis centers.⁵ Chronic hemodialysis patients with central lines were noted to have the greatest rate of infections and antibiotic usage (6.4 per 100 patient months). The next highest group was dialysis patients with grafts (2.4 per 100 patient months), followed by patients with fistulas (1.8 per 100 patient months). Vancomycin was most commonly chosen for all antibiotic starts (73%). Interestingly, vancomycin was followed by cefazolin and third- and/or fourth-generation cephalosporin, which are risk factors for the emergence of multidrug-resistant, Gram-negative bacteria that are highly linked to increased morbidity and mortality rates. The U.S. Renal Data System stated in its 2009 report that the use of antibiotic therapy has increased from 31% in 1994 to 41% in 2007.⁵

In reviewing inappropriate choices of antimicrobial prescribing, D’Agata compared prescriptions given to the Healthcare Infection Control Practices Advisory Committee to determine whether the correct antibiotic was chosen. In 164 vancomycin prescriptions, 20% were categorized as inappropriate.⁵ In another study done by Zvonar and colleagues, 163 prescriptions of vancomycin were reviewed, and 12% were considered inappropriate.⁶

Snyder and colleagues examined 278 patients on hemodialysis, and over a 1-year period, 32% of these patients received ≥ 1 antimicrobial with 29.8% of the doses classified as inappropriate.⁷ The most common category for inappropriate prescribing of antimicrobials was not meeting the criteria for diagnosing infections (52.9% of cases). The second leading cause of inappropriate prescription for infections was not meeting criteria for diagnosing specific skin and skin-structure infections (51.6% of cases). Another common category was failure to choose a narrower spectrum antimicrobial prescription (26.8%).⁷ Attention to the indications and duration of antimicrobial treatment accounted for 20.3% of all inappropriate doses. Correction of these problems with use of an ASP could reduce the patient’s exposure to unneeded or inappropriate antibiotics by 22% to 36% and decrease hospital costs between $200,000 to $900,000.⁵

Rosa and colleagues discussed adherence to an ASP and the effects on mortality in hospitalized cancer patients with febrile neutropenia (FN).⁸ A prospective cohort study was performed in a single facility over a 2-year period. Patients admitted with cancer and FN were followed for 28 days. The mortality rates of those treated with ASP protocol antibiotics were compared with those treated with other antibiotic regimens. One hundred sixty-nine patients with 307 episodes of FN were included. The rate of adherence to ASP recommendations was 53% with the mortality of this cohort 9.4% (29 patients).⁸

Older patients were more likely to be treated according to ASP recommendations, whereas patients with comorbidities were not treated with ASP guidelines, Rosa and colleagues noted.⁸ No explanation was given, but statistical testing did uphold these findings, ensuring that the results were correctly interpreted. The 28-day mortality during FN was related to several factors, including nonadherence with ASP recommendations (P = .001) relapsing diseases stages (P = .001), and time to antibiotic start therapy > 1 hour (P = .001). Adherence to the ASP was independently associated with a higher survival rate (P = .03), whereas mortality was attributable to infection in all 29 patients who died.

Nowak and colleagues reviewed the clinical and economic benefits of an ASP using a pre- and postanalysis of potential patients who might benefit from recommendations of the ASP.⁹ Subjects included adult inpatients with pneumonia or abdominal sepsis. Recommendations from ASP that were followed decreased expenditures by 9.75% during the first year and remained stable in the following years. The cumulative cost savings was about $1.7 million. Rates of nosocomial infections decreased, and pre- and postcomparison of survival and lengths of stay for patients with pneumonia (n = 2,186) or abdominal sepsis (n = 225) revealed no significant differences. Investigators argued that this finding may have been due to the hospital’s initiation of other concurrent IC programs.

Doron and colleagues conducted a survey identifying characteristics of ASP practices and factors associated with the presence of an ASP.¹⁰ Surveys were received from 48 states (North and South Dakota were not included) and Puerto Rico. Surveys were received from 406 providers, and 96.4% identified some form of ASP. Barriers to implementation included staffing constraints (69.4%) and insufficient funding (0.6%).¹⁰

About 38% of the responses stated ASP was being used for adults and pediatric patients, whereas 58.8% were used for adults only.¹⁰ The ASP teams were composed of a variety of providers, including infectious disease (ID) physicians (70.7%), IC professionals (51.1%), and clinical microbiologists (38.6%). Additional barriers to implementing an ASP were found as insufficient medical staff buy-in (32.8%), not high on the priority list (22.2%), and too many other things to consider or deal with at the time (42.8%). Interestingly, 41.1% of the subjects in facilities without an ASP responded that providers agree with limiting the use of antimicrobials compared with 66.9% of subjects in hospitals with an ASP. Factors linked to having an ASP included having an ID consultation service, an ID fellowship program, an ID pharmacist, larger hospitals, annual admissions > 10,000, having a published antibiogram, and being a teaching hospital.

Establishment of an ASP

The Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) issued guidelines in 2007 for developing an institutional ASP to enhance antimicrobial stewardship and help prevent antimicrobial resistance in hospitals.¹¹ The ASP may vary among facilities based on available resources.

When developing an ASP, 2 core strategies are necessary. The core measures are proactive and are usually conducted by an ID clinical pharmacist assigned to the ASP in collaboration with the ID physician. These strategies are not mutually exclusive and include a prospective audit with interventions provided to the clinicians, resulting in decreased inappropriate use of antimicrobials or a formulary restriction and preauthorization to help reduce antimicrobial usage and related cost.

Supplemental elements may be considered and prioritized as to the core antimicrobial stewardship strategies based on local practice pattern and resources.¹¹ Factors to consider include education, which is considered to be an essential element of the ASP. Although education is important, it alone is only somewhat effective in changing clinicians’ prescribing practices. Guidelines and clinical pathways are elements set forth in institutional management protocols for common and potentially serious infections such as intravascular catheter-related infections, hospital- and community-acquired pneumonia, bloodstream infections, and complicated urinary tract infections among other types.

Another consideration is antimicrobial cycling. This process refers to the specific schedule of alternating specific antimicrobials or antimicrobial classes to prevent or reverse the development of antimicrobial resistance. Insufficient data on antimicrobial cycling currently exist to affect major changes in practice. This element, however, could be implemented in certain institutions if needed based on the reported bacterial resistance pattern.

Antimicrobial order forms can be used to help monitor the implementation of formulated institutional clinical practice pathways. However, the authors feel that documenting this indication in the clinician notes may be adequate and save time for everyone involved; additionally, reviewing combination therapy, which if avoided, may prevent the emergence of resistance. Although combination therapy is needed in certain clinical diagnostic situations, careful consideration of its use is essential.

Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse.Streamlining or de-escalation of therapy by using a narrower spectrum agent, based on culture and sensitivity results, prevents duplicative therapy with a patient when double coverage is not indicated or intended. Another goal is the discontinuation of therapy based on negative culture results and lack of supporting clinical signs and symptoms of infection. Dose optimization and adjustment should also be reviewed. Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse and subsequent potentially avoidable adverse effects.

Parenteral to oral conversion from IV to oral administration (IV to oral) antimicrobials must be considered when the patient is clinically and hemodynamically stable, thus limiting the length of hospital stays and health care costs. However, it is important to keep in mind pharmacokinetic studies examining the bioavailability of antibiotics are usually conducted with healthy volunteers. Therefore, when treating patients who are elderly, on multiple medications, or severely ill, proper usage of these antibiotics is required. Also, having antibiotics with excellent bioavailability does not necessarily mean switching from IV to oral routes when treating serious infections such as bacteremia. Special consideration should be given when changing the route of administration. In addition, approval—or at least notification by the treating physician or ID specialist—should be included in the absence of an institutional policy, allowing for automatic IV to oral conversion.

The ASP Team

The participation of specific clinicians has been suggested as key to having a successful ASP team.¹² Members should include an ID physician (director) who serves as the lead physician and supervises the overall function of the ASP, makes recommendations to the ASP team, and contributes to the educational activities. A clinical ID pharmacist (codirector) provides suggestions to clinicians on preferred first-line antimicrobials and reviews medication orders for antimicrobials and resistance patterns, microbiological data, patient data, and clinical information. The codirector also tracks any ASP-related data and submits monitoring reports on a regular basis.

If accessible, an IC professional should participate, implementing and monitoring prevention strategies that decrease health care-associated infections. These infections play a significant role in reducing MDROs and decreasing the use of antibiotics. Additionally, the IC professional can assist in the early identification of patients with MDROs, aid patient placement on transmission-based precautions, and flag a patient in the medical record for hightened awareness. Also, IC professionals promote hand hygiene, standard precautions, and contribute to infection prevention strategies, such as hospital bundle practices, to prevent catheter-associated bloodstream infections and ventilator-associated pneumonias, among others.

If possible, a microbiologist who can prepare culture and susceptibility data to optimize antimicrobial management and conduct timely documentation of microbial pathogens should be a member of the team. Microbiologists can report organism susceptibility, assist in the surveillance of specific organisms, and provide early identification of patients with MDROs that require transmission-based precautions. The microbiologist can perform a semiannual update of a local antibiogram while reporting antimicrobial susceptibility profiles. Based on the information gathered, microbiologists can provide new drug panels to the members of the ASP, who will decide which antibiotic panel will be used. Another possible member of the ASP team is a program analyst who provides data retrieval, performs data analysis, and delivers necessary reports to the team.

It is the responsibility of medical staff to review and implement suggestions made by the ASP when appropriate. However, these suggestions are not considered a substitute for clinical decisions, and discretion is required when treating individual patients. The VHA, in response to the IDSA/SHEA published guidelines, chartered an antimicrobial stewardship task force in May 2011 with the sole purpose “To optimize the care of Veterans by developing, deploying and monitoring a national-level strategic plan for improvements in antimicrobial therapy management.”¹ In 2011, the Office of Inspector General in a combined assessment program summary report for management of MDROs in VHA facilities recommended that “the Under Secretary for Health, in conjunction with VISN and facility senior managers, ensures that facilities develop policies and programs that control and reduce antimicrobial agent use.”¹³

In 2012, the VHA conducted a survey to obtain baseline data regarding ASP activities, presence of dedicated personnel, current related practice policies, available resources, and outcomes. There were 140 voluntary participating VA facilities, of which 130 had inpatient services. The survey found that 26 facilities (20%) did not have an attending ID physician, 49 facilities (38%) reported having an ASP, 19 facilities (15%) had developed policy in place addressing de-escalation of antimicrobials, 87 facilities (67%) had not developed a business plan for an ASP, and 61 facilities (47%) had completed a medication usage evaluation.¹⁴ Feedback following the analysis of the survey data recommended integrating more ID personnel as needed, along with the development of ASP teams for all facilities with inpatient services, who would have the authority to change the antimicrobial therapy selection and have policies in place related to ASP principles.

Conclusions

Increased MDROs and decreased anti-infective development requires stricter management of antibiotics. An ASP is essential in any hospital or health care facility to decrease the incidence of resistance and improve patient care. The ASP is a collaborative effort that involves multiple specialties and departments. A successful ASP is one that changes based on local prescribing trends and resistance patterns while focusing on a patient as an individual. 

Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.

Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.

An antimicrobial stewardship program (ASP) is designed to provide guidance for the safe andcost-effective use of antimicrobial agents. This evidence-based approach addresses the correct selection of antimicrobial agents, dosages, routes of administration, and duration of therapy. In other words, the ASP necessitates the right drug, the right time, the right amount, and the right duration.¹ The ASP reduces the development of multidrug-resistant organisms (MDROs), adverse drug events (such as antibiotic-associated diarrhea and renal toxicity), hospital length of stay, collateral damage (development of Clostridium difficile colitis), and health care costs. Review of the literature has shown the ASP reduces hospital stays among patients with acute bacterial-skin and skin-structure infections along with other costly infections.² 

The ASP is not a new concept, but it is a hot topic. A successful ASP cannot be achieved without the support of the hospital leadership to determine and provide the needed resources. Its success stems from being a joint collaborative effort between pharmacy, medicine, infection control (IC), microbiology, and information technology. The purpose of the ASP is to ensure proper use of antimicrobials within the health care system through the development of a formal, interdisciplinary team. The primary goal of the ASP is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance. 

In today’s world, health care clinicians are dealing with a global challenge of MDROs such as Enterococcus faecium, Staphylococcus aureus (S aureus), Klebsiella pneumonia, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE), better known as “bugs without borders.”³ According to the CDC, antibiotic-resistant infections affect at least 2 million people in the U.S. annually and result in > 23,000 deaths.² According to Thomas Frieden, director of the CDC, the pipeline of new antibiotics is nearly empty for the short term, and new drugs could be a decade away from discovery and approval by the FDA.²

Literature Review

Pasquale and colleagues conducted a retrospective, observational chart review on 62 patients who were admitted for bacterial-skin and skin-structure infections (S aureus, MRSA, MSSA, and Pseudomonas aeruginosa).⁴ The data examined patient demographic characteristics, comorbidities, specific type of skin infection (the most common being cellulitis, major or deep abscesses, and surgical site infections), microbiology, surgical interventions, and recommendations obtained from the ASP committee.

The primary goal of the antimicrobial stewardship program is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance.The ASP recommendations were divided into 5 categories, including dosage changes, de-escalation, antibiotic regimen changes, infectious disease (ID) consults, and other (not described). The ASP offered 85 recommendations, and acceptance of the ASP recommendations by physicians was 95%. The intervention group had a significantly lower length of stay (4.4 days vs 6.2 days, P < .001); and the 30-day all-cause readmission rate was also significantly lower (6.5% vs 16.71%, P = .05). However, the skin and skin-related structures readmission rate did not differ significantly (3.33% vs 6.27%). It was impossible for the investigators to determine exact differences in the amount of antimicrobials used in the intervention group vs the historical controls, because the historical data were based on ICD-9 codes, which may explain the nonsignificant finding.⁴

D’Agata reviewed the antimicrobial usage and ASP programs in dialysis centers.⁵ Chronic hemodialysis patients with central lines were noted to have the greatest rate of infections and antibiotic usage (6.4 per 100 patient months). The next highest group was dialysis patients with grafts (2.4 per 100 patient months), followed by patients with fistulas (1.8 per 100 patient months). Vancomycin was most commonly chosen for all antibiotic starts (73%). Interestingly, vancomycin was followed by cefazolin and third- and/or fourth-generation cephalosporin, which are risk factors for the emergence of multidrug-resistant, Gram-negative bacteria that are highly linked to increased morbidity and mortality rates. The U.S. Renal Data System stated in its 2009 report that the use of antibiotic therapy has increased from 31% in 1994 to 41% in 2007.⁵

In reviewing inappropriate choices of antimicrobial prescribing, D’Agata compared prescriptions given to the Healthcare Infection Control Practices Advisory Committee to determine whether the correct antibiotic was chosen. In 164 vancomycin prescriptions, 20% were categorized as inappropriate.⁵ In another study done by Zvonar and colleagues, 163 prescriptions of vancomycin were reviewed, and 12% were considered inappropriate.⁶

Snyder and colleagues examined 278 patients on hemodialysis, and over a 1-year period, 32% of these patients received ≥ 1 antimicrobial with 29.8% of the doses classified as inappropriate.⁷ The most common category for inappropriate prescribing of antimicrobials was not meeting the criteria for diagnosing infections (52.9% of cases). The second leading cause of inappropriate prescription for infections was not meeting criteria for diagnosing specific skin and skin-structure infections (51.6% of cases). Another common category was failure to choose a narrower spectrum antimicrobial prescription (26.8%).⁷ Attention to the indications and duration of antimicrobial treatment accounted for 20.3% of all inappropriate doses. Correction of these problems with use of an ASP could reduce the patient’s exposure to unneeded or inappropriate antibiotics by 22% to 36% and decrease hospital costs between $200,000 to $900,000.⁵

Rosa and colleagues discussed adherence to an ASP and the effects on mortality in hospitalized cancer patients with febrile neutropenia (FN).⁸ A prospective cohort study was performed in a single facility over a 2-year period. Patients admitted with cancer and FN were followed for 28 days. The mortality rates of those treated with ASP protocol antibiotics were compared with those treated with other antibiotic regimens. One hundred sixty-nine patients with 307 episodes of FN were included. The rate of adherence to ASP recommendations was 53% with the mortality of this cohort 9.4% (29 patients).⁸

Older patients were more likely to be treated according to ASP recommendations, whereas patients with comorbidities were not treated with ASP guidelines, Rosa and colleagues noted.⁸ No explanation was given, but statistical testing did uphold these findings, ensuring that the results were correctly interpreted. The 28-day mortality during FN was related to several factors, including nonadherence with ASP recommendations (P = .001) relapsing diseases stages (P = .001), and time to antibiotic start therapy > 1 hour (P = .001). Adherence to the ASP was independently associated with a higher survival rate (P = .03), whereas mortality was attributable to infection in all 29 patients who died.

Nowak and colleagues reviewed the clinical and economic benefits of an ASP using a pre- and postanalysis of potential patients who might benefit from recommendations of the ASP.⁹ Subjects included adult inpatients with pneumonia or abdominal sepsis. Recommendations from ASP that were followed decreased expenditures by 9.75% during the first year and remained stable in the following years. The cumulative cost savings was about $1.7 million. Rates of nosocomial infections decreased, and pre- and postcomparison of survival and lengths of stay for patients with pneumonia (n = 2,186) or abdominal sepsis (n = 225) revealed no significant differences. Investigators argued that this finding may have been due to the hospital’s initiation of other concurrent IC programs.

Doron and colleagues conducted a survey identifying characteristics of ASP practices and factors associated with the presence of an ASP.¹⁰ Surveys were received from 48 states (North and South Dakota were not included) and Puerto Rico. Surveys were received from 406 providers, and 96.4% identified some form of ASP. Barriers to implementation included staffing constraints (69.4%) and insufficient funding (0.6%).¹⁰

About 38% of the responses stated ASP was being used for adults and pediatric patients, whereas 58.8% were used for adults only.¹⁰ The ASP teams were composed of a variety of providers, including infectious disease (ID) physicians (70.7%), IC professionals (51.1%), and clinical microbiologists (38.6%). Additional barriers to implementing an ASP were found as insufficient medical staff buy-in (32.8%), not high on the priority list (22.2%), and too many other things to consider or deal with at the time (42.8%). Interestingly, 41.1% of the subjects in facilities without an ASP responded that providers agree with limiting the use of antimicrobials compared with 66.9% of subjects in hospitals with an ASP. Factors linked to having an ASP included having an ID consultation service, an ID fellowship program, an ID pharmacist, larger hospitals, annual admissions > 10,000, having a published antibiogram, and being a teaching hospital.

Establishment of an ASP

The Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) issued guidelines in 2007 for developing an institutional ASP to enhance antimicrobial stewardship and help prevent antimicrobial resistance in hospitals.¹¹ The ASP may vary among facilities based on available resources.

When developing an ASP, 2 core strategies are necessary. The core measures are proactive and are usually conducted by an ID clinical pharmacist assigned to the ASP in collaboration with the ID physician. These strategies are not mutually exclusive and include a prospective audit with interventions provided to the clinicians, resulting in decreased inappropriate use of antimicrobials or a formulary restriction and preauthorization to help reduce antimicrobial usage and related cost.

Supplemental elements may be considered and prioritized as to the core antimicrobial stewardship strategies based on local practice pattern and resources.¹¹ Factors to consider include education, which is considered to be an essential element of the ASP. Although education is important, it alone is only somewhat effective in changing clinicians’ prescribing practices. Guidelines and clinical pathways are elements set forth in institutional management protocols for common and potentially serious infections such as intravascular catheter-related infections, hospital- and community-acquired pneumonia, bloodstream infections, and complicated urinary tract infections among other types.

Another consideration is antimicrobial cycling. This process refers to the specific schedule of alternating specific antimicrobials or antimicrobial classes to prevent or reverse the development of antimicrobial resistance. Insufficient data on antimicrobial cycling currently exist to affect major changes in practice. This element, however, could be implemented in certain institutions if needed based on the reported bacterial resistance pattern.

Antimicrobial order forms can be used to help monitor the implementation of formulated institutional clinical practice pathways. However, the authors feel that documenting this indication in the clinician notes may be adequate and save time for everyone involved; additionally, reviewing combination therapy, which if avoided, may prevent the emergence of resistance. Although combination therapy is needed in certain clinical diagnostic situations, careful consideration of its use is essential.

Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse.Streamlining or de-escalation of therapy by using a narrower spectrum agent, based on culture and sensitivity results, prevents duplicative therapy with a patient when double coverage is not indicated or intended. Another goal is the discontinuation of therapy based on negative culture results and lack of supporting clinical signs and symptoms of infection. Dose optimization and adjustment should also be reviewed. Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse and subsequent potentially avoidable adverse effects.

Parenteral to oral conversion from IV to oral administration (IV to oral) antimicrobials must be considered when the patient is clinically and hemodynamically stable, thus limiting the length of hospital stays and health care costs. However, it is important to keep in mind pharmacokinetic studies examining the bioavailability of antibiotics are usually conducted with healthy volunteers. Therefore, when treating patients who are elderly, on multiple medications, or severely ill, proper usage of these antibiotics is required. Also, having antibiotics with excellent bioavailability does not necessarily mean switching from IV to oral routes when treating serious infections such as bacteremia. Special consideration should be given when changing the route of administration. In addition, approval—or at least notification by the treating physician or ID specialist—should be included in the absence of an institutional policy, allowing for automatic IV to oral conversion.

The ASP Team

The participation of specific clinicians has been suggested as key to having a successful ASP team.¹² Members should include an ID physician (director) who serves as the lead physician and supervises the overall function of the ASP, makes recommendations to the ASP team, and contributes to the educational activities. A clinical ID pharmacist (codirector) provides suggestions to clinicians on preferred first-line antimicrobials and reviews medication orders for antimicrobials and resistance patterns, microbiological data, patient data, and clinical information. The codirector also tracks any ASP-related data and submits monitoring reports on a regular basis.

If accessible, an IC professional should participate, implementing and monitoring prevention strategies that decrease health care-associated infections. These infections play a significant role in reducing MDROs and decreasing the use of antibiotics. Additionally, the IC professional can assist in the early identification of patients with MDROs, aid patient placement on transmission-based precautions, and flag a patient in the medical record for hightened awareness. Also, IC professionals promote hand hygiene, standard precautions, and contribute to infection prevention strategies, such as hospital bundle practices, to prevent catheter-associated bloodstream infections and ventilator-associated pneumonias, among others.

If possible, a microbiologist who can prepare culture and susceptibility data to optimize antimicrobial management and conduct timely documentation of microbial pathogens should be a member of the team. Microbiologists can report organism susceptibility, assist in the surveillance of specific organisms, and provide early identification of patients with MDROs that require transmission-based precautions. The microbiologist can perform a semiannual update of a local antibiogram while reporting antimicrobial susceptibility profiles. Based on the information gathered, microbiologists can provide new drug panels to the members of the ASP, who will decide which antibiotic panel will be used. Another possible member of the ASP team is a program analyst who provides data retrieval, performs data analysis, and delivers necessary reports to the team.

It is the responsibility of medical staff to review and implement suggestions made by the ASP when appropriate. However, these suggestions are not considered a substitute for clinical decisions, and discretion is required when treating individual patients. The VHA, in response to the IDSA/SHEA published guidelines, chartered an antimicrobial stewardship task force in May 2011 with the sole purpose “To optimize the care of Veterans by developing, deploying and monitoring a national-level strategic plan for improvements in antimicrobial therapy management.”¹ In 2011, the Office of Inspector General in a combined assessment program summary report for management of MDROs in VHA facilities recommended that “the Under Secretary for Health, in conjunction with VISN and facility senior managers, ensures that facilities develop policies and programs that control and reduce antimicrobial agent use.”¹³

In 2012, the VHA conducted a survey to obtain baseline data regarding ASP activities, presence of dedicated personnel, current related practice policies, available resources, and outcomes. There were 140 voluntary participating VA facilities, of which 130 had inpatient services. The survey found that 26 facilities (20%) did not have an attending ID physician, 49 facilities (38%) reported having an ASP, 19 facilities (15%) had developed policy in place addressing de-escalation of antimicrobials, 87 facilities (67%) had not developed a business plan for an ASP, and 61 facilities (47%) had completed a medication usage evaluation.¹⁴ Feedback following the analysis of the survey data recommended integrating more ID personnel as needed, along with the development of ASP teams for all facilities with inpatient services, who would have the authority to change the antimicrobial therapy selection and have policies in place related to ASP principles.

Conclusions

Increased MDROs and decreased anti-infective development requires stricter management of antibiotics. An ASP is essential in any hospital or health care facility to decrease the incidence of resistance and improve patient care. The ASP is a collaborative effort that involves multiple specialties and departments. A successful ASP is one that changes based on local prescribing trends and resistance patterns while focusing on a patient as an individual. 

Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.

Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.

An antimicrobial stewardship program (ASP) is designed to provide guidance for the safe andcost-effective use of antimicrobial agents. This evidence-based approach addresses the correct selection of antimicrobial agents, dosages, routes of administration, and duration of therapy. In other words, the ASP necessitates the right drug, the right time, the right amount, and the right duration.¹ The ASP reduces the development of multidrug-resistant organisms (MDROs), adverse drug events (such as antibiotic-associated diarrhea and renal toxicity), hospital length of stay, collateral damage (development of Clostridium difficile colitis), and health care costs. Review of the literature has shown the ASP reduces hospital stays among patients with acute bacterial-skin and skin-structure infections along with other costly infections.² 

The ASP is not a new concept, but it is a hot topic. A successful ASP cannot be achieved without the support of the hospital leadership to determine and provide the needed resources. Its success stems from being a joint collaborative effort between pharmacy, medicine, infection control (IC), microbiology, and information technology. The purpose of the ASP is to ensure proper use of antimicrobials within the health care system through the development of a formal, interdisciplinary team. The primary goal of the ASP is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance. 

In today’s world, health care clinicians are dealing with a global challenge of MDROs such as Enterococcus faecium, Staphylococcus aureus (S aureus), Klebsiella pneumonia, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species (ESKAPE), better known as “bugs without borders.”³ According to the CDC, antibiotic-resistant infections affect at least 2 million people in the U.S. annually and result in > 23,000 deaths.² According to Thomas Frieden, director of the CDC, the pipeline of new antibiotics is nearly empty for the short term, and new drugs could be a decade away from discovery and approval by the FDA.²

Literature Review

Pasquale and colleagues conducted a retrospective, observational chart review on 62 patients who were admitted for bacterial-skin and skin-structure infections (S aureus, MRSA, MSSA, and Pseudomonas aeruginosa).⁴ The data examined patient demographic characteristics, comorbidities, specific type of skin infection (the most common being cellulitis, major or deep abscesses, and surgical site infections), microbiology, surgical interventions, and recommendations obtained from the ASP committee.

The primary goal of the antimicrobial stewardship program is to optimize clinical outcomes while minimizing unintended consequences related to antimicrobial usage, such as toxicities or the emergence of resistance.The ASP recommendations were divided into 5 categories, including dosage changes, de-escalation, antibiotic regimen changes, infectious disease (ID) consults, and other (not described). The ASP offered 85 recommendations, and acceptance of the ASP recommendations by physicians was 95%. The intervention group had a significantly lower length of stay (4.4 days vs 6.2 days, P < .001); and the 30-day all-cause readmission rate was also significantly lower (6.5% vs 16.71%, P = .05). However, the skin and skin-related structures readmission rate did not differ significantly (3.33% vs 6.27%). It was impossible for the investigators to determine exact differences in the amount of antimicrobials used in the intervention group vs the historical controls, because the historical data were based on ICD-9 codes, which may explain the nonsignificant finding.⁴

D’Agata reviewed the antimicrobial usage and ASP programs in dialysis centers.⁵ Chronic hemodialysis patients with central lines were noted to have the greatest rate of infections and antibiotic usage (6.4 per 100 patient months). The next highest group was dialysis patients with grafts (2.4 per 100 patient months), followed by patients with fistulas (1.8 per 100 patient months). Vancomycin was most commonly chosen for all antibiotic starts (73%). Interestingly, vancomycin was followed by cefazolin and third- and/or fourth-generation cephalosporin, which are risk factors for the emergence of multidrug-resistant, Gram-negative bacteria that are highly linked to increased morbidity and mortality rates. The U.S. Renal Data System stated in its 2009 report that the use of antibiotic therapy has increased from 31% in 1994 to 41% in 2007.⁵

In reviewing inappropriate choices of antimicrobial prescribing, D’Agata compared prescriptions given to the Healthcare Infection Control Practices Advisory Committee to determine whether the correct antibiotic was chosen. In 164 vancomycin prescriptions, 20% were categorized as inappropriate.⁵ In another study done by Zvonar and colleagues, 163 prescriptions of vancomycin were reviewed, and 12% were considered inappropriate.⁶

Snyder and colleagues examined 278 patients on hemodialysis, and over a 1-year period, 32% of these patients received ≥ 1 antimicrobial with 29.8% of the doses classified as inappropriate.⁷ The most common category for inappropriate prescribing of antimicrobials was not meeting the criteria for diagnosing infections (52.9% of cases). The second leading cause of inappropriate prescription for infections was not meeting criteria for diagnosing specific skin and skin-structure infections (51.6% of cases). Another common category was failure to choose a narrower spectrum antimicrobial prescription (26.8%).⁷ Attention to the indications and duration of antimicrobial treatment accounted for 20.3% of all inappropriate doses. Correction of these problems with use of an ASP could reduce the patient’s exposure to unneeded or inappropriate antibiotics by 22% to 36% and decrease hospital costs between $200,000 to $900,000.⁵

Rosa and colleagues discussed adherence to an ASP and the effects on mortality in hospitalized cancer patients with febrile neutropenia (FN).⁸ A prospective cohort study was performed in a single facility over a 2-year period. Patients admitted with cancer and FN were followed for 28 days. The mortality rates of those treated with ASP protocol antibiotics were compared with those treated with other antibiotic regimens. One hundred sixty-nine patients with 307 episodes of FN were included. The rate of adherence to ASP recommendations was 53% with the mortality of this cohort 9.4% (29 patients).⁸

Older patients were more likely to be treated according to ASP recommendations, whereas patients with comorbidities were not treated with ASP guidelines, Rosa and colleagues noted.⁸ No explanation was given, but statistical testing did uphold these findings, ensuring that the results were correctly interpreted. The 28-day mortality during FN was related to several factors, including nonadherence with ASP recommendations (P = .001) relapsing diseases stages (P = .001), and time to antibiotic start therapy > 1 hour (P = .001). Adherence to the ASP was independently associated with a higher survival rate (P = .03), whereas mortality was attributable to infection in all 29 patients who died.

Nowak and colleagues reviewed the clinical and economic benefits of an ASP using a pre- and postanalysis of potential patients who might benefit from recommendations of the ASP.⁹ Subjects included adult inpatients with pneumonia or abdominal sepsis. Recommendations from ASP that were followed decreased expenditures by 9.75% during the first year and remained stable in the following years. The cumulative cost savings was about $1.7 million. Rates of nosocomial infections decreased, and pre- and postcomparison of survival and lengths of stay for patients with pneumonia (n = 2,186) or abdominal sepsis (n = 225) revealed no significant differences. Investigators argued that this finding may have been due to the hospital’s initiation of other concurrent IC programs.

Doron and colleagues conducted a survey identifying characteristics of ASP practices and factors associated with the presence of an ASP.¹⁰ Surveys were received from 48 states (North and South Dakota were not included) and Puerto Rico. Surveys were received from 406 providers, and 96.4% identified some form of ASP. Barriers to implementation included staffing constraints (69.4%) and insufficient funding (0.6%).¹⁰

About 38% of the responses stated ASP was being used for adults and pediatric patients, whereas 58.8% were used for adults only.¹⁰ The ASP teams were composed of a variety of providers, including infectious disease (ID) physicians (70.7%), IC professionals (51.1%), and clinical microbiologists (38.6%). Additional barriers to implementing an ASP were found as insufficient medical staff buy-in (32.8%), not high on the priority list (22.2%), and too many other things to consider or deal with at the time (42.8%). Interestingly, 41.1% of the subjects in facilities without an ASP responded that providers agree with limiting the use of antimicrobials compared with 66.9% of subjects in hospitals with an ASP. Factors linked to having an ASP included having an ID consultation service, an ID fellowship program, an ID pharmacist, larger hospitals, annual admissions > 10,000, having a published antibiogram, and being a teaching hospital.

Establishment of an ASP

The Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA) issued guidelines in 2007 for developing an institutional ASP to enhance antimicrobial stewardship and help prevent antimicrobial resistance in hospitals.¹¹ The ASP may vary among facilities based on available resources.

When developing an ASP, 2 core strategies are necessary. The core measures are proactive and are usually conducted by an ID clinical pharmacist assigned to the ASP in collaboration with the ID physician. These strategies are not mutually exclusive and include a prospective audit with interventions provided to the clinicians, resulting in decreased inappropriate use of antimicrobials or a formulary restriction and preauthorization to help reduce antimicrobial usage and related cost.

Supplemental elements may be considered and prioritized as to the core antimicrobial stewardship strategies based on local practice pattern and resources.¹¹ Factors to consider include education, which is considered to be an essential element of the ASP. Although education is important, it alone is only somewhat effective in changing clinicians’ prescribing practices. Guidelines and clinical pathways are elements set forth in institutional management protocols for common and potentially serious infections such as intravascular catheter-related infections, hospital- and community-acquired pneumonia, bloodstream infections, and complicated urinary tract infections among other types.

Another consideration is antimicrobial cycling. This process refers to the specific schedule of alternating specific antimicrobials or antimicrobial classes to prevent or reverse the development of antimicrobial resistance. Insufficient data on antimicrobial cycling currently exist to affect major changes in practice. This element, however, could be implemented in certain institutions if needed based on the reported bacterial resistance pattern.

Antimicrobial order forms can be used to help monitor the implementation of formulated institutional clinical practice pathways. However, the authors feel that documenting this indication in the clinician notes may be adequate and save time for everyone involved; additionally, reviewing combination therapy, which if avoided, may prevent the emergence of resistance. Although combination therapy is needed in certain clinical diagnostic situations, careful consideration of its use is essential.

Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse.Streamlining or de-escalation of therapy by using a narrower spectrum agent, based on culture and sensitivity results, prevents duplicative therapy with a patient when double coverage is not indicated or intended. Another goal is the discontinuation of therapy based on negative culture results and lack of supporting clinical signs and symptoms of infection. Dose optimization and adjustment should also be reviewed. Using the appropriate antimicrobial dose based on the specific pathogen, patient characteristic, source of infection, along with the pharmacokinetic and pharmacodynamics should be reviewed to prevent antimicrobial overuse and subsequent potentially avoidable adverse effects.

Parenteral to oral conversion from IV to oral administration (IV to oral) antimicrobials must be considered when the patient is clinically and hemodynamically stable, thus limiting the length of hospital stays and health care costs. However, it is important to keep in mind pharmacokinetic studies examining the bioavailability of antibiotics are usually conducted with healthy volunteers. Therefore, when treating patients who are elderly, on multiple medications, or severely ill, proper usage of these antibiotics is required. Also, having antibiotics with excellent bioavailability does not necessarily mean switching from IV to oral routes when treating serious infections such as bacteremia. Special consideration should be given when changing the route of administration. In addition, approval—or at least notification by the treating physician or ID specialist—should be included in the absence of an institutional policy, allowing for automatic IV to oral conversion.

The ASP Team

The participation of specific clinicians has been suggested as key to having a successful ASP team.¹² Members should include an ID physician (director) who serves as the lead physician and supervises the overall function of the ASP, makes recommendations to the ASP team, and contributes to the educational activities. A clinical ID pharmacist (codirector) provides suggestions to clinicians on preferred first-line antimicrobials and reviews medication orders for antimicrobials and resistance patterns, microbiological data, patient data, and clinical information. The codirector also tracks any ASP-related data and submits monitoring reports on a regular basis.

If accessible, an IC professional should participate, implementing and monitoring prevention strategies that decrease health care-associated infections. These infections play a significant role in reducing MDROs and decreasing the use of antibiotics. Additionally, the IC professional can assist in the early identification of patients with MDROs, aid patient placement on transmission-based precautions, and flag a patient in the medical record for hightened awareness. Also, IC professionals promote hand hygiene, standard precautions, and contribute to infection prevention strategies, such as hospital bundle practices, to prevent catheter-associated bloodstream infections and ventilator-associated pneumonias, among others.

If possible, a microbiologist who can prepare culture and susceptibility data to optimize antimicrobial management and conduct timely documentation of microbial pathogens should be a member of the team. Microbiologists can report organism susceptibility, assist in the surveillance of specific organisms, and provide early identification of patients with MDROs that require transmission-based precautions. The microbiologist can perform a semiannual update of a local antibiogram while reporting antimicrobial susceptibility profiles. Based on the information gathered, microbiologists can provide new drug panels to the members of the ASP, who will decide which antibiotic panel will be used. Another possible member of the ASP team is a program analyst who provides data retrieval, performs data analysis, and delivers necessary reports to the team.

It is the responsibility of medical staff to review and implement suggestions made by the ASP when appropriate. However, these suggestions are not considered a substitute for clinical decisions, and discretion is required when treating individual patients. The VHA, in response to the IDSA/SHEA published guidelines, chartered an antimicrobial stewardship task force in May 2011 with the sole purpose “To optimize the care of Veterans by developing, deploying and monitoring a national-level strategic plan for improvements in antimicrobial therapy management.”¹ In 2011, the Office of Inspector General in a combined assessment program summary report for management of MDROs in VHA facilities recommended that “the Under Secretary for Health, in conjunction with VISN and facility senior managers, ensures that facilities develop policies and programs that control and reduce antimicrobial agent use.”¹³

In 2012, the VHA conducted a survey to obtain baseline data regarding ASP activities, presence of dedicated personnel, current related practice policies, available resources, and outcomes. There were 140 voluntary participating VA facilities, of which 130 had inpatient services. The survey found that 26 facilities (20%) did not have an attending ID physician, 49 facilities (38%) reported having an ASP, 19 facilities (15%) had developed policy in place addressing de-escalation of antimicrobials, 87 facilities (67%) had not developed a business plan for an ASP, and 61 facilities (47%) had completed a medication usage evaluation.¹⁴ Feedback following the analysis of the survey data recommended integrating more ID personnel as needed, along with the development of ASP teams for all facilities with inpatient services, who would have the authority to change the antimicrobial therapy selection and have policies in place related to ASP principles.

Conclusions

Increased MDROs and decreased anti-infective development requires stricter management of antibiotics. An ASP is essential in any hospital or health care facility to decrease the incidence of resistance and improve patient care. The ASP is a collaborative effort that involves multiple specialties and departments. A successful ASP is one that changes based on local prescribing trends and resistance patterns while focusing on a patient as an individual. 

Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.

Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the U.S. Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.