The Rare Case of Mycobacterium marinum in Vietnam.

Mycobacterium marinum is slow-growing mycobacteria, a common atypical mycobacteria that causes opportunistic infections in humans and is capable of causing disease in the skin and soft tissues. This cutaneous disorder has a wide clinical spectrum with cutaneous inflammation and granulomatous nodules that can spread along with the distribution of the lymphatic system. The infection predominantly affects the extremities. The accurate diagnosis is often challenging, requiring the presence of bacteria at the lesion. Conventional treatment usually requires a combination of antibiotics and long-term use. To report a case of M. marinum infection successfully treated with ethambutol and clarithromycin, we present a 71-year-old male patient who lives in the coastal area developed purulent hand inflammation and many subcutaneous nodular lesions. The diagnosis was based on the analysis of hand nodules using histopathology, Ziehl-Neelsen staining, and polymerase chain reaction. This positive outcome gives insight into a rare skin infection in Vietnam and strengthens suggested treatment guidelines.