Atypical mycobacteria

Non-TB non-leprosy mycobacteria that are ubiquitous in the environment. Important in immunosuppressed and may cause occasional disease in healthy individuals, usually by direct inoculation.

  • Mycobacterium marinum aka fish tank/swimming pool granuloma. Caused by water habitant especially stagnant warm water. Causes nodule/pustule/ulcer on hand with sporotrichoid spread. Heals spontaneously within a few months but is more commonly treated with ciprofloxacin and clarithromycin.

  • Mycobacterium ulcerans - causes Buruli ulcer found in environment, infection by direct inoculation ulceration down to fat. Treatment with surgery + antibiotics.

  • MAI complex - common in HIV skin lesions are nodules, pustules, ulcers, abscesses, panniculitis other organ systems may be involved.