From the Guidelines
The recommended treatment for cat scratch disease is a 5-day course of azithromycin, with a dose of 500 mg on day 1, followed by 250 mg daily for 4 more days for patients weighing ≥45.5 kg, and 10 mg/kg on day 1, then 5 mg/kg on days 2–5 for those weighing <45.5 kg, as supported by the Infectious Diseases Society of America guidelines 1.
Key Considerations
- The disease is caused by the bacterium Bartonella henselae, which is transmitted through cat scratches or bites.
- Azithromycin has been shown to be effective in reducing lymph node size and resolving symptoms, with an 80% reduction in lymph node size at 30 days compared to placebo 1.
- Alternative antibiotics, such as trimethoprim-sulfamethoxazole, ciprofloxacin, or rifampin, may be considered for patients who cannot take azithromycin.
- Supportive care, including pain management with over-the-counter medications like acetaminophen or ibuprofen, and warm compresses to reduce lymph node swelling and discomfort, may be sufficient for uncomplicated cases in immunocompetent patients.
Special Considerations
- Immunocompromised patients may require longer antibiotic courses or intravenous antibiotics.
- Surgical drainage may be necessary for significantly enlarged or suppurative lymph nodes.
- The diagnosis of cat scratch disease can be challenging, and serological testing, PCR, or a positive Warthin-Starry silver stain of infected lymph node tissue may be useful in confirming the diagnosis 1.
From the Research
Cat Scratch Disease Diagnosis and Treatment
- Cat scratch disease is an infection caused by Bartonella henselae, typically acquired from exposure to an infected kitten or cat 2, 3.
- The most common manifestation of human disease is lymphadenitis, with atypical forms of infection including Parinaud oculoglandular syndrome, stellate neuroretinitis, and hepatosplenic infection 2, 3.
- Diagnosis of cat scratch disease can be established through the presence of regional lymphadenopathy, cat contact, and papula, with additional procedures including indirect fluorescent antibody assays and PCR 4.
Recommended Treatment
- The majority of cases of cat scratch disease occurring in normal hosts do not require anti-infective therapy for resolution of infection 2, 3.
- In complicated cases, treatment with antibiotics such as azithromycin, rifampicin, ciprofloxacin, trimethoprim-sulfamethoxazole, and gentamicin may be recommended 2, 3, 4.
- Azithromycin therapy has been associated with more rapid diminution in size of infected lymph nodes 2.
- In immunosuppressed patients, a comprehensive evaluation is crucial, including a detailed medical history, physical examination, and comprehensive histological and microbiological assessments 5.
Antibiotic Therapy
- Antibiotic treatment may be considered for cat scratch disease patients with severe symptoms, with effective agents including rifampicin, ciprofloxacin, trimethoprim sulfamethoxazole, and gentamicin 2, 3, 4.
- Erythromycin and doxycycline have also been shown to be effective in treating severe or persistent cases of cat scratch disease 6.
- Combination therapy with azithromycin and rifampicin may be effective in treating cat scratch disease with multiorgan involvement 5.