Granulomatous hepatitis due to Bartonella henselae mimicking stage IV malignancy

Abstract

Introduction: Hepatosplenic cat-scratch disease (HS-CSD) is a rare manifestation of Bartonella henselae infection in immunocompetent adults and may closely mimic haematological malignancy. Case description: A 62-year-old woman with a history of breast cancer presented with an eight-week history of fever, night sweats and weight loss. A fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) revealed hypermetabolic hepatosplenic lesions, retroperitoneal lymphadenopathy and a focal acetabular bone lesion, strongly suggesting stage IV lymphoma or metastatic disease. Bone marrow biopsy showed no evidence of malignancy; liver biopsy revealed caseous necrotising granulomas. Mycobacterial polymerase chain reaction (PCR) and cultures were negative. Bartonella serology demonstrated a high IgG titre (>1:1.280), while tissue PCR was borderline positive. Treatment with azithromycin and rifampicin for four weeks resulted in clinical improvement and resolution of constitutional symptoms. Conclusion: HS-CSD can closely mimic advanced malignancy. In patients with prolonged fever, visceral lesions and feline exposure, B. henselae infection should be considered early in the diagnostic workup.