DNA-FINGERPRINTING AND PHENOTYPING OF MYCOBACTERIUM-TUBERCULOSIS ISOLATES FROM HUMAN-IMMUNODEFICIENCY-VIRUS (HIV)-SEROPOSITIVE AND HIV-SERONEGATIVE PATIENTS IN TANZANIA

With the purpose of determining whether the risk of infection with a p articular clone of Mycobacterium tuberculosis is influenced by the hum an immunodeficiency virus (HIV) status of the host, we analyzed and co mpared 68 mycobacterial isolates obtained from HIV-seropositive patien ts with tuberculosis (TB) in Dar es Salaam, Tanzania, with 66 mycobact erial isolates obtained from HIV-seronegative patients with TB in the same geographical region by using both DNA fingerprinting and classica l phenotyping methods. One hundred one different IS6110 fingerprinting patterns were observed in the 134 isolates. The level of diversity of the DNA fingerprints observed in the HIV-seropositive group was compa rable to the level of the diversity observed in tile HIV-seronegative group. Resistance to a single anti-TB drug was found in 8.8% of the te sted isolates, and 3.2% of the isolates were resistant to more than on e anti-TB drug, The drug susceptibility profiles were not significantl y difference between the two groups of isolates compared in the presen t study. Phenotypic characteristics which classify M. tuberculosis str ains as belonging to the Asian subgroup correlated with a low IS6110 c opy number per isolate. However, the occurrence of Asian subgroup stra ins was not associated with the HIV status of the patients. The result s of the study suggested an equal risk of infection with a defined M. tuberculosis clone for HIV-seropositive and HIV-seronegative individua ls.