A PROSPECTIVE EVALUATION OF MYCOBACTERIUM-AVIUM COMPLEX COLONIZATION OF THE RESPIRATORY AND GASTROINTESTINAL TRACTS OF PERSONS WITH HUMAN-IMMUNODEFICIENCY-VIRUS INFECTION

To describe the natural history of Mycobacterium avium complex (MAC) i n the respiratory or gastrointestinal tract of persons with human immu nodeficiency virus (HIV) infection, 67 HIV-infected patients with CD4 cell counts <200/mm3 and initial negative MAC blood cultures were fol lowed prospectively. Patients were screened every 3 months with cultur es and smears of sputum, rectal swab, and blood for mycobacteria. Four teen patients (20.9%) developed positive blood cultures for MAC (23.4% /year). Sputum cultures revealed MAC in 3 (21%) of the 14 patients at 1, 2, and 8 months before dissemination; no smears were positive. No r ectal swab cultures or smears were positive before dissemination. Colo nization of the respiratory and gastrointestinal tracts in persons wit h HIV infection and <200/mm3 CD4+ cells is infrequently detected with currently available techniques. Screening cultures and smears of sputu m and stool do not appear to be sensitive methods for detection of ear ly MAC infection.