Mycobacterium marinum infection in Child
The typical skin lesion consists of a pustule or nodule and develops on an extremity 2-3 weeks after exposure. Nodules may ulcerate, suppurate, and spread via lymphangitic spread (about 25% of cases). In more severe infections, deeper manifestations such as tenosynovitis, arthritis, bursitis, or osteomyelitis may be seen. In immunosuppressed patients, disease can disseminate to the lungs or other systems; bacteremia is rare.
In general, the infection is usually mild and self-limited, and lesions may heal over a period of 1-2 years if left untreated, although treatment is recommended.
Related topics: Mycobacterium avium-intracellulare, Mycobacterium kansasii, Mycobacterium fortuitum, Mycobacterium chelonae, Mycobacterium scrofulaceum, Mycobacterium tuberculosis, and Atypical mycobacterial infections
A31.9 – Mycobacterial infection, unspecified
373438001 – Infection due to Mycobacterium marinum
Differential Diagnosis & Pitfalls
- Other infections such as sporotrichosis, blastomycosis, coccidioidomycosis, nocardiosis, tularemia, cutaneous tuberculosis, cutaneous leishmaniasis, and actinomycosis may have a similar lymphangitic spread from cutaneous inoculation. Exposure and travel history are key for diagnosis.
- Isolated lesions may mimic other cutaneous mycobacterial infections or granulomatous disease.
- Sarcoidosis rarely ulcerates or spreads along lymphatics.
- Cellulitis has a background of erythema and a more rapid onset and spread.
- Cutaneous lymphoma may have associated fevers and weight loss.
- Sarcoma may have associated fevers and weight loss.
- Bacterial abscess has an acute onset.
- Pyoderma gangrenosum bleeds easily and appears vascular.
- Vasculitis does not usually have an exophytic growth pattern.
- Superficial thrombophlebitis
- Granuloma annulare rarely ulcerates.
- Hypertrophic lichen planus is highly pruritic and usually located on the shins.
- Foreign body reaction, especially to sea urchin spines or barnacles given the possibility of shared clinical history.
- Cutaneous anthrax
- Majocchi granuloma