Mycobacterium marinum infection in an older woman with extensive verrucous skin lesions: a case report.

Mycobacterium marinum is a nontuberculous mycobacterium and an opportunistic pathogen which infects humans. Here, we report a case of an 87-year-old female who had extensive verrucous skin lesions on her upper limbs for 18 months. The patient was diagnosed with Mycobacterium marinum infection by pathology and quantitative polymerase chain reaction (qPCR) assay of skin tissue. After five months of oral rifampicin and clarithromycin, the skin lesions regressed completely.