Cat-Scratch Disease Mimicking Neoplastic Etiology in a Complex Clinical Presentation: A Case Report.

Cat-scratch disease (CSD), caused by Bartonella henselae (B. henselae), typically presents with regional lymphadenopathy following a cat scratch or bite. We report a case of a 50-year-old man with a complex medical history including HIV, Crohn's disease, coronary artery disease, and bipolar disorder, who presented with progressively enlarging cervical lymphadenopathy associated with fever, night sweats, and myalgias. Initial evaluation suggested a neoplastic etiology, prompting extensive laboratory investigations and imaging. However, subsequent history prompted serological testing and markedly elevated Bartonella antibody titers, leading to a clinical diagnosis of CSD. Empirical doxycycline therapy was initiated, resulting in the complete resolution of symptoms. This case underscores the importance of considering CSD in the differential diagnosis of lymphadenopathy, particularly in people living with HIV regardless of immunocompetency, and highlights the challenges of diagnosis and management in complex patients.