Cat scratch disease encephalopathy in an immunocompetent patient.

Cat scratch disease (CSD) is typically a self-limited regional lymphadenopathy in children and young adults that is caused by Bartonella henselae. The majority of CSD cases resolve spontaneously; however, many systemic complications have been described. We report an unusual case of CSD presenting as an epitrochlear arm mass and complicated by encephalopathy. Identification of B. henselae DNA in the affected lymph node and cerebrospinal fluid confirmed the diagnosis of CSD. Systemic antibiotic therapy was administered and the patient improved without any neurological deficit.