Consider Cat-Scratch Disease in Setting With Fever, Kittens

MAUI, HAWAII — “Ask about pets in every febrile patient you see” was one of the take-home messages from Dr. Jay M. Lieberman as he discussed infections you can get from your pets.

And in particular, he said, “Consider cat-scratch disease in any patient with fever of unknown origin who has contact with cats—particularly if they're kittens.”

He presented several cases of children with prolonged fevers who remained without a diagnosis, despite extensive evaluations, until the possibility of cat-scratch disease was entertained and a history of contact with kittens was obtained. The diagnosis of cat-scratch disease often can be made from the history and physical examination, and serologies may not be reliable, Dr. Lieberman said at a meeting sponsored by the University Childrens Medical Group and the American Academy of Pediatrics.

Kittens are more likely to cause cat-scratch disease than are older cats. The disease is caused by Bartonella henselae, and approximately 40% of cats are bacteremic with the organism, explained Dr. Lieberman, professor of clinical pediatrics at the University of California, Irvine.

Cat-scratch disease is transmitted to humans through scratches, licks, or bites from kittens, less often from older cats, and sometimes from dogs.

A primary papule may be seen 3–12 days after inoculation time, followed 7–60 days (average 12–14 days) later by regional lymphadenopathy that may suppurate or regress over 2–4 months. Lymphadenopathy usually involves the nodes that drain the site of inoculation. Fever occurs in half of patients, and malaise, anorexia, and headache also may occur.

The area around the nodes may be noninflamed but can be warm, tender, and erythematous, Dr. Lieberman said at the meeting, which also was sponsored by California Chapter 2 of the AAP. As many as 30% of nodes will suppurate spontaneously.

Atypical presentations of cat-scratch disease included prolonged fever/fever of unknown origin, granulomatous hepatitis, conjunctivitis with preauricular adenopathy (Parinaud's oculoglandular syndrome), encephalopathy/encephalitis, osteomyelitis, and ocular disease.

Although patients may be treated with rifampin or gentamicin or trimethoprim-sulfamethoxazole (TMP/SMZ), or a combination of anti-infectives, Dr. Lieberman does not routinely recommend their use. “In general, we have not treated our patients with antimicrobial therapy,” he said. “Most patients do not require specific therapy, and the illness resolves on its own.”

One prospective randomized trial of azithromycin vs. placebo found a significantly greater decrease in lymph node size in azithromycin-treated patients at 30 days, but there was no significant difference thereafter (Pediatr. Infect. Dis. J. 1998;17:447-52).

Dr. Lieberman also noted that approximately 5%–15% of dog bites lead to infections, as do 20%–50% of cat bites. Pasteurella species, short gram-negative coccobacilli that are part of the normal flora of cats and dogs, are isolated from 75% of infections from cat bites and 50% of infections from dog bites. Pasteurella organisms are not susceptible to cephalexin or dicloxacillin, Dr. Lieberman said.

To help prevent infection from bites, wounds should be cleaned, debrided, and closed. Bite wounds should be reevaluated in 1–2 days. When indicated, there may be a need for tetanus and/or rabies prophylaxis.

Antibiotic prophylaxis is indicated for puncture wounds (including all cat bites), bites over tendons, joints, and bone; bites on the face and/or genitals; bites involving an immunocompromised person; and bites that cannot be well cleaned and debrided. Antibiotic prophylaxis, when indicated, may be used for 48–72 hours.

Amoxicillin-clavulanate is the antibiotic of choice for prevention or treatment of animal bite wound infections, he said. Dr. Lieberman disclosed that he is on a speakers' bureau for GlaxoSmithKline.

Regional lymphadenopathy, as shown in this 8-year-old patient, can appear 7–60 days after a primary papule. Courtesy Dr. Sherif Emil

MAUI, HAWAII — “Ask about pets in every febrile patient you see” was one of the take-home messages from Dr. Jay M. Lieberman as he discussed infections you can get from your pets.

And in particular, he said, “Consider cat-scratch disease in any patient with fever of unknown origin who has contact with cats—particularly if they're kittens.”

He presented several cases of children with prolonged fevers who remained without a diagnosis, despite extensive evaluations, until the possibility of cat-scratch disease was entertained and a history of contact with kittens was obtained. The diagnosis of cat-scratch disease often can be made from the history and physical examination, and serologies may not be reliable, Dr. Lieberman said at a meeting sponsored by the University Childrens Medical Group and the American Academy of Pediatrics.

Kittens are more likely to cause cat-scratch disease than are older cats. The disease is caused by Bartonella henselae, and approximately 40% of cats are bacteremic with the organism, explained Dr. Lieberman, professor of clinical pediatrics at the University of California, Irvine.

Cat-scratch disease is transmitted to humans through scratches, licks, or bites from kittens, less often from older cats, and sometimes from dogs.

A primary papule may be seen 3–12 days after inoculation time, followed 7–60 days (average 12–14 days) later by regional lymphadenopathy that may suppurate or regress over 2–4 months. Lymphadenopathy usually involves the nodes that drain the site of inoculation. Fever occurs in half of patients, and malaise, anorexia, and headache also may occur.

The area around the nodes may be noninflamed but can be warm, tender, and erythematous, Dr. Lieberman said at the meeting, which also was sponsored by California Chapter 2 of the AAP. As many as 30% of nodes will suppurate spontaneously.

Atypical presentations of cat-scratch disease included prolonged fever/fever of unknown origin, granulomatous hepatitis, conjunctivitis with preauricular adenopathy (Parinaud's oculoglandular syndrome), encephalopathy/encephalitis, osteomyelitis, and ocular disease.

Although patients may be treated with rifampin or gentamicin or trimethoprim-sulfamethoxazole (TMP/SMZ), or a combination of anti-infectives, Dr. Lieberman does not routinely recommend their use. “In general, we have not treated our patients with antimicrobial therapy,” he said. “Most patients do not require specific therapy, and the illness resolves on its own.”

One prospective randomized trial of azithromycin vs. placebo found a significantly greater decrease in lymph node size in azithromycin-treated patients at 30 days, but there was no significant difference thereafter (Pediatr. Infect. Dis. J. 1998;17:447-52).

Dr. Lieberman also noted that approximately 5%–15% of dog bites lead to infections, as do 20%–50% of cat bites. Pasteurella species, short gram-negative coccobacilli that are part of the normal flora of cats and dogs, are isolated from 75% of infections from cat bites and 50% of infections from dog bites. Pasteurella organisms are not susceptible to cephalexin or dicloxacillin, Dr. Lieberman said.

To help prevent infection from bites, wounds should be cleaned, debrided, and closed. Bite wounds should be reevaluated in 1–2 days. When indicated, there may be a need for tetanus and/or rabies prophylaxis.

Antibiotic prophylaxis is indicated for puncture wounds (including all cat bites), bites over tendons, joints, and bone; bites on the face and/or genitals; bites involving an immunocompromised person; and bites that cannot be well cleaned and debrided. Antibiotic prophylaxis, when indicated, may be used for 48–72 hours.

Amoxicillin-clavulanate is the antibiotic of choice for prevention or treatment of animal bite wound infections, he said. Dr. Lieberman disclosed that he is on a speakers' bureau for GlaxoSmithKline.

Regional lymphadenopathy, as shown in this 8-year-old patient, can appear 7–60 days after a primary papule. Courtesy Dr. Sherif Emil

MAUI, HAWAII — “Ask about pets in every febrile patient you see” was one of the take-home messages from Dr. Jay M. Lieberman as he discussed infections you can get from your pets.

And in particular, he said, “Consider cat-scratch disease in any patient with fever of unknown origin who has contact with cats—particularly if they're kittens.”

He presented several cases of children with prolonged fevers who remained without a diagnosis, despite extensive evaluations, until the possibility of cat-scratch disease was entertained and a history of contact with kittens was obtained. The diagnosis of cat-scratch disease often can be made from the history and physical examination, and serologies may not be reliable, Dr. Lieberman said at a meeting sponsored by the University Childrens Medical Group and the American Academy of Pediatrics.

Kittens are more likely to cause cat-scratch disease than are older cats. The disease is caused by Bartonella henselae, and approximately 40% of cats are bacteremic with the organism, explained Dr. Lieberman, professor of clinical pediatrics at the University of California, Irvine.

Cat-scratch disease is transmitted to humans through scratches, licks, or bites from kittens, less often from older cats, and sometimes from dogs.

A primary papule may be seen 3–12 days after inoculation time, followed 7–60 days (average 12–14 days) later by regional lymphadenopathy that may suppurate or regress over 2–4 months. Lymphadenopathy usually involves the nodes that drain the site of inoculation. Fever occurs in half of patients, and malaise, anorexia, and headache also may occur.

The area around the nodes may be noninflamed but can be warm, tender, and erythematous, Dr. Lieberman said at the meeting, which also was sponsored by California Chapter 2 of the AAP. As many as 30% of nodes will suppurate spontaneously.

Atypical presentations of cat-scratch disease included prolonged fever/fever of unknown origin, granulomatous hepatitis, conjunctivitis with preauricular adenopathy (Parinaud's oculoglandular syndrome), encephalopathy/encephalitis, osteomyelitis, and ocular disease.

Although patients may be treated with rifampin or gentamicin or trimethoprim-sulfamethoxazole (TMP/SMZ), or a combination of anti-infectives, Dr. Lieberman does not routinely recommend their use. “In general, we have not treated our patients with antimicrobial therapy,” he said. “Most patients do not require specific therapy, and the illness resolves on its own.”

One prospective randomized trial of azithromycin vs. placebo found a significantly greater decrease in lymph node size in azithromycin-treated patients at 30 days, but there was no significant difference thereafter (Pediatr. Infect. Dis. J. 1998;17:447-52).

Dr. Lieberman also noted that approximately 5%–15% of dog bites lead to infections, as do 20%–50% of cat bites. Pasteurella species, short gram-negative coccobacilli that are part of the normal flora of cats and dogs, are isolated from 75% of infections from cat bites and 50% of infections from dog bites. Pasteurella organisms are not susceptible to cephalexin or dicloxacillin, Dr. Lieberman said.

To help prevent infection from bites, wounds should be cleaned, debrided, and closed. Bite wounds should be reevaluated in 1–2 days. When indicated, there may be a need for tetanus and/or rabies prophylaxis.

Antibiotic prophylaxis is indicated for puncture wounds (including all cat bites), bites over tendons, joints, and bone; bites on the face and/or genitals; bites involving an immunocompromised person; and bites that cannot be well cleaned and debrided. Antibiotic prophylaxis, when indicated, may be used for 48–72 hours.

Amoxicillin-clavulanate is the antibiotic of choice for prevention or treatment of animal bite wound infections, he said. Dr. Lieberman disclosed that he is on a speakers' bureau for GlaxoSmithKline.

Regional lymphadenopathy, as shown in this 8-year-old patient, can appear 7–60 days after a primary papule. Courtesy Dr. Sherif Emil