ATYPICAL MYCOBACTERIUM INFECTIONS OF THE UPPER EXTREMITY

Thirty-three patients with culture-positive atypical Mycobacterium inf ections of the upper extremity underwent surgical debridement and anti microbial therapy. The causative atypical organism was M. marinum in 1 2 cases, M. avium-intracellulare in 7, M. terrae in 4, M. chelonei in 4, M. kansasii in 3, M. fortuitum in 2, and M. ulcerans in 1. The teno synovium was the most common location of infection (14 patients). The average follow-up period was 36 months. Duration of antimicrobial ther apy averaged 10 months. The average delay between onset of symptoms to correct diagnosis was 1 year. There were seven superficial infections ; six were caused by M. marinum and one was caused by M. ulcerans. All of these cutaneous infections resolved following incisional or excisi onal biopsy and pharmacologic therapy. The remaining 26 infections inv olved the deeper tissues, and M. avium-intracellulare was the most com mon organism. The immune status of the host was an overwhelming predic tor of eventual outcome. In the 15 patients with competent immune syst ems, resolution occurred in 13. However, in the immunocompromised pati ent population, only 4 of the 10 had resolution of deep infection at t ime of the follow-up evaluation.