A rare case of hepatic abscess due to Aggregatibacter aphrophilus: Case report and literature review

Aggregatibacter aphrophilus, a fastidious Gram-negative member of the Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella group, is an exceptionally rare cause of hepatic abscess, particularly in immunocompetent individuals. We describe a case of a healthy, middle-aged man who presented with a 5-day history of cyclical fevers, chills, and night sweats. Computed tomography imaging revealed a solitary hepatic lesion, initially suspicious for malignancy. Magnetic resonance cholangiopancreatography confirmed a hepatic abscess. Culture from a computed tomography-guided aspirate identified A. aphrophilus as the causative organism. Despite empiric broad-spectrum antibiotics and drainage, the patient continued to experience febrile episodes until culture-directed therapy led to clinical resolution. He received 3 weeks of intravenous ceftriaxone 2 g q24 h and PO metronidazole 500 mg q8 h and percutaneous drainage. Upon follow-up with infectious disease, no recurrence was noted upon review of repeat computed tomography imaging. This case highlights the importance of early microbiological identification and targeted treatment, even in healthy hosts.