Clinical presentation and treatment of Mycobacterium marinum infection as seen in 12 cases

Background and objective: Mycobacterium marinum (M.m.) is the causative pat hogen of skin infections that have been called "swimming pool granulomas". An increasing number of reports that deep structures are involved in these infections was the reason for studying the clinical presentation and respon se of the ionfection to different therapeutic regimens. Patients and methods: All patients (eight men, four women, age range 18-73 years) were included in whom, between January 1991 and February 1995, M.m. infection had been proven by culture. The clinical data of these patients w ere retrospectively obtained by standardized questionnaire. Results: The infection was limited to the skin in four of the twelve patien ts, deep structures only were involved in three, and five had both. infecti ons limited to the skin were successfully treated with sulphamethoxazole an d trimethoprim or with tetracylcines, while rifampicin, alone or in combina tion with ethambutol, was efficacious when deep structures were involved. N o surgical intervention was - or should be - performed. Conclusions: Infections with M.m. often involve deep structures, even in th e absence of the skin being involved. The term "swimming pool granuloma" is , therefore, misleading when the infection is limited to he skin. A history of a chronic and indolent course, frequent changes of doctor acid striking polypharmacy in its treatment are pointers to this infection.