Mycobacterium marinum cutanous infection misdiagnosed as sporotrichosis in a patient with systemic lupus erythematosus: A case report

Mycobacterium marinum(M. marinum), a slow-growing bacterium in freshwater and seawater, can cause cutanous and extracutaneous infections. A fisher-woman with systemic lupus erythematosus (SLE) presented with chronic polymorphic rashes in a lymphangitic pattern was initially misdiagnosed as sporotrichosis. The final diagnosis of M. marinum and Candida dubliniensis co-infection was confirmed based on the skin histopathology, pustule culture, MetaCAP sequencing and effective antibiotic combination treatments. •SLE patients are prone to infections due to the immunocompromised condition.•Mycobacterium marinum can mimic sporotrichosis but MetaCAP sequencing aids diagnosis.•Combination antibiotics are recommended for deep tissue M. marinum infection.