Prospective 7-year monitoring of MAC bacteremia in HIV-positive Swedish patients.

OBJECTIVE: To record the cumulative incidence of Mycobacterium avium complex (MAC) bacteremia among HIV-infected patients and to study colonization in relation to symptoms of infection. METHODS: In a prospective study, 61 patients with a CD4 count less-than-or-eq, slant200x106/L were followed by cultures from sputum, feces and blood every 3--6 months and for development of MAC bacteremia and clinical symptoms. The main end-points were MAC bacteremia and death. RESULTS: From the start in November 1989 to January 1997 about 34% had developed MAC bacteremia with a median follow-up of 22 months. At the time of positive blood cultures, all but one patient had symptoms consistent with disseminated MAC infection. Positive cultures from respiratory and gastrointestinal tract were recorded before MAC bacteremia in only four patients. All but one had symptoms at the time of positive blood culture. CONCLUSIONS: The incidence of MAC bacteremia was similar to figures in other studies. The presence of symptoms in close relation to positive blood cultures supports late colonization and late infection in HIV disease. Screening patients with samples from the respiratory and gastrointestinal tracts is not useful