RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM ANALYSIS DETECTING A COMMUNITY-BASED TUBERCULOSIS OUTBREAK AMONG PERSONS INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS

Analysis of restriction fragment length polymorphisms (RFLP) was used to investigate an increase in tuberculosis (TB) among noninstitutional ized human immunodeficiency virus (HIV)-infected persons in King Count y, Washington. Using the IS6110 insertion sequence, RFLP analysis was done on Mycobacterium tuberculosis isolates from 18 HIV-infected patie nts and 10 randomly selected patients without HIV risk factors. Six HI V-infected patients with the same M. tuberculosis strain had contact a t one or more of three bars as their only common exposure. Two other H IV-infected persons, a patient and a health care worker who had close contact, had matching strains. Isolates from the 10 remaining HIV-infe cted patients and the 10 patients without HIV risk factors had differe nt DNA patterns. Analysis of RFLP patterns revealed a community outbre ak of TB among HIV-infected persons who had not been previously linked following conventional investigation by the health department. This t echnique deserves further evaluation as an epidemiologic tool in the i nvestigation of TB.