Two Decades of Insights into Nontuberculous Mycobacterial Hand Infections

The objective of our study is to describe the clinical presentation, management, and outcome of a large cohort with nontuberculous mycobacteria (NTM) hand infection.

We reviewed the medical records of all adults (≥18 years) managed at the Mayo Clinic (Rochester, MN) for NTM hand infection between 1998 and 2018.

Our cohort included 81 patients. The median age was 61.3 (interquartile range 51.7, 69.6) years; 39.5% were immunocompromised, and 67.9% reported a triggering exposure preceding infection. Infection was deep in 64.2% and disseminated in 3.7%. Up to 16.0% received intralesional steroids because of misdiagnosis with an inflammatory process. Immunocompromised patients had deeper infection, and fewer reports of a triggering exposure. Mycobacterium marinum, Mycobacterium avium complex, and Mycobacterium chelonae/abscessus complex were the most common species. The median antibiotic duration was 6.1 (interquartile range 4.6, 9.9) months. Deep infection and infection with species other than M marinum were associated with using a greater number of antibiotics for combination therapy and an extended duration of treatment. Immunosuppression was also associated with longer courses of antibiotic therapy. Surgery was performed in 86.5% and 32.4% required multiple procedures. Ten patients, mostly with superficial infections, were treated with antibiotics alone. The 5-year cumulative rate of treatment failure was 30.3% (95% confidence interval, 20.9-44.0). Immunosuppression and intralesional steroid use were risk factors for failure.

Treatment of NTM hand infection usually requires surgery and antibiotics, but antibiotics alone may occasionally be attempted in select cases. Immunosuppression and intralesional steroids are risk factors for treatment failure.