Fusobacterium Nucleatum Empyema: An Atypical Presentation

A 40-year-old man presented to the emergency room and was evaluated in the internal medicine department for unexplained weight loss, asthenia, anorexia and night sweats over the previous 2 months. After a loculated pleural effusion was identified on thoracic computed tomography, purulent fluid was drained from the lung and Fusobacterium nucleatum was isolated. The patient was successfully treated for 27 days with amoxicillin-clavulanic acid. This was an atypical presentation of a common micro-organism implicated in lung infections. LEARNING POINTS: Empyema due to Fusobacterium nucleatum can have an atypical presentation, manifesting only with unexplained weight loss and night sweats. F. nucleatum lung infection usually responds well to treatment with common antibiotics. In patients with unexplained weight loss, the differential diagnosis should include cancer, tuberculosis and atypical presentations of other bacterial infections.