Liver Mass Caused by Mycobacterium fortuitum: A Rare Case Diagnosed by EUS-FNA.

Mycobacterium fortuitum is associated with skin and soft-tissue infections, yet isolated liver involvement is rare. A 67-year-old asymptomatic man was referred for endoscopic ultrasound (EUS) to evaluate a gastric lesion and an incidental liver mass. EUS revealed a heterogeneous liver mass that was sampled. Pathology revealed necrotic granulomatous inflammation and positive acid-fast bacilli stain with M. fortuitum deoxyribonucleic acid. Levofloxacin plus trimethoprim and sulfamethoxazole for 3 months were used for complete resolution of liver lesion. Isolated nontuberculous liver involvement is uncommon. We report the first case of a liver mass caused by M. fortuitum diagnosed by EUS-fine needle aspiration.