Case Presentation: A 22-year-old male with history of diabetes mellitus type I presents with 3 weeks of right inguinal pain with CT scan which showed a enlarged lymph node measuring 3.5 cm x 2.8 cm which was subsequently biopsied and showed necrotizing granulomatous lymphadenitis. He then presented with status epilepticus approximately 1 week after his biopsy. He had been experiencing worsening fevers up to 104°F, malaise, nausea, vomiting, and 10-15-pound weight loss for the past week prior to hospitalization. He works as an HVAC apprentice, has exposure to multiple pets including dogs, cats, and birds (unsure of vaccination status), also works as a transporter of feed to a cattle farm. EEG showed severe diffuse non-specific cerebral dysfunction. Magnetic resonance imaging and echocardiogram was unremarkable. Given his continued cerebral dysfunction, a lumbar puncture was performed, and cerebral spinal fluid culture and polymerase chain reaction were performed which were negative. Bartonella serology was positive for both IgM and IgG antibodies. He was switched to doxycycline and rifampin and completed a 4-week course with no residual deficits from his encephalitis.
Discussion: Cat scratch disease caused by Bartonella henselae is typically a self-limiting infection. The benign course of the disease involves appearance of a papule at the inoculation site with involvement of regional lymph nodes, associated with mild fever, and fatigue with resolution in 6-12 weeks. Lymph node examination typically shows granulomas with central necrosis and occasionally localized abscess. EEG typically shows diffuse slowing.Neurological involvement with Bartonella henselae infection is rare with 0.17% to 2% of patients progressing to encephalitis. Progression to encephalitis usually occurs early in the course of the disease by week 3 with predominant complaint of headache followed by rapid decline in mental status and coma. Diagnostic testing includes serology with high IgG titers (1:256) as strongly indicative of infection. Treatment of systemic cat scratch disease include doxycycline and rifampin. Typically there are no lasting effects from neurological manifestations of cat scratch disease.
Conclusions: This case demonstrates the importance of recognizing Bartonella henselae infection and recognizing patient that need to be treated with antibiotics versus watchful waiting.