Mycobacterium marinum flexor tenosynovitis of the hand diagnosed by tissue polymerase chain reaction: a case report

Mycobacterium marinum, a non-tuberculous mycobacterium, is commonly found in contaminated water or fish and can lead to deep infections of the hand. Identification of this bacterium is challenging, and traditional microbial culture and identification methods may result in delayed diagnosis and treatment. Tissue polymerase chain reaction is a diagnostic method that directly amplifies genus-specific primers from infected tissues obtained during surgery to identify mycobacterial species, and this approach provides results faster than conventional culture methods. We report a case of refractory infectious flexor tenosynovitis of the hand, in which the causative organism had not been identified for several months through smears, culture, and detection tests. Through extensive debridement and tissue polymerase chain reaction as an identification test, the patient was diagnosed with M. marinum infection and successfully treated.