PROTECTION FROM MYCOBACTERIUM-AVIUM COMPLEX DISEASE IN HUMAN-IMMUNODEFICIENCY-VIRUS - INFECTED PERSONS WITH A HISTORY OF TUBERCULOSIS

Risk of Mycobacterium avium complex disease was examined in human immu nodeficiency virus (HIV)-infected patients with and without a history of tuberculosis, Information was obtained by retrospective review of c harts of patients in HIV clinics in 10 US cities. Among 1363 patients with <200 CD4 cells/mm(3) seen at Grady Memorial Hospital (GMH), 11 (1 7%) of 66 with a history of a positive purified protein derivative (PP D) skin test acquired M. avium infection, while 29 (16%) of 185 who we re PPD-negative (but not anergic) did not (P = .85). Only 4 (8%) of 49 GMH patients with a history of tuberculosis acquired M. avium infecti on compared with 252 (19%) of 1314 GMH patients without a history of t uberculosis (P = .05), Proportional hazards analysis of risk factors f or M. avium infection among 441 persons with and 8702 persons without a history of tuberculosis in 9 other cities confirmed protection from M. avium infection in persons with a history of tuberculosis (relative risk, 0.52; 95% confidence interval, 0.36-0.76; P < .001), Prior tube rculosis provides protection against M. avium infection in HIV-infecte d persons, possibly by stimulation of antimycobacterial immunity.