Adult systemic cat scratch disease associated with therapy for hepatitis C

BACKGROUND We describe the first case of systemic cat scratch disease in a patient receiving peginterferon alpha-2a and ribavirin for treatment of hepatitis C. Cases of adult systemic CSD are extremely infrequent and immunomodulatory treatment for hepatitis C has been associated with aberrant host responses to common pathogens. CASE PRESENTATION A 52 year old man being treated for hepatitis C presented with diffuse lymphadenopathy, weight loss, fevers and splenic lesions. Symptoms were initially confused with adverse effects of his regimen, delaying recognition of his infection. Diagnostic investigation, including histopathology, microbiology and serologic parameters, confirmed that his illness was due to disseminated cat scratch disease with Bartonella henselae. CONCLUSION Disseminated CSD is exceptionally rare in adults. We describe the first case of disseminated cat scratch disease associated with peginterferon alpha and ribavirin to alert clinicians of the need to be aware of unusual manifestations of common infections in this population.