Mycobacterium marinum Infection and Interferon-Gamma Release Assays Cross-Reactivity: A Case Report

Mycobacterium marinum (M. marinum) is a pathogen that causes skin and soft tissue infections in people who work with contaminated water, such as fish handlers. M. marinum infection is mostly limited to patients with compromised immune systems. As per current guidelines, susceptibility testing is not routinely recommended^, although sporadic cases have been reported with resistance to routinely prescribed anti-tuberculous drugs. We report a case of a 61-year-old male taking adalimumab with ulcerative skin and soft tissue infection with positive interferon-gamma release assays (IGRA) identified as M. marinum and the treatment challenges involved in this case.