Mycobacterium Marinum Infection of the Skin Differential Diagnoses

Updated: Mar 24, 2022
  • Author: Kirstin Altman, MD; Chief Editor: Dirk M Elston, MD  more...
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Diagnostic Considerations

Also consider the following:

  • Infection with atypical mycobacteria (eg, Mycobacterium kansasii, Mycobacterium chelonae, Mycobacterium avium-intracellulare, Mycobacterium ulcerans) [22]
  • Tinea manuum [24]
  • Botryomycosis ( Staphylococcus aureus)
  • Deep fungal infection (eg, with Cryptococcus neoformans, Histoplasma capsulatum, Coccidioides immitis, or Blastomyces dermatitis)
  • Dematiaceous fungi (chromomycosis or phaeohyphomycosis)
  • Infection with Francisella tularensis

Sporotrichosis is most commonly associated with nodular lymphangitis. For this reason, M marinum infection can often be misdiagnosed as sporotrichosis. Patients sometimes undergo long courses of antifungal treatments before further spreading of the Mycobacterium elicits a repeat biopsy and culture.

Involved joints may be misdiagnosed as inflammatory arthritis, and the joint may be inappropriately injected with a corticosteroid. Corticosteroid injection can result in marked progression of the disease. [26]

Differential Diagnoses