Mycobacterium marinum infections of the hand

Fifteen patients had culture proven Mycobacterium marinum infections of the hand; 11 had injured their hands while fishing in water around Long Island. No patient had type I lesions (verrucal), six patients had type II lesions (subcutaneous granulomas), and nine patients had type III lesions (deep). Histologic examination showed noncaseating granulomas in all cases. A specific defect in the patients' lymphocytes ability to respond to M. marinum antigens was identified. A combination of surgery and tetracycline provided effective treatment. Follow-up averaged 2 1/2 years.