Background: In this report we study tuberculosis transmission in HIV infected patients using molecular epidemiological methods.
Patients and methods: We have studied 60 M. tuberculosis isolates from 30 HIV infected cases, and their clinical-epidemiological data. Susceptibility to tuberculostatic agents and electrophoretic patterns using RFLPs (restriction fragment length polymorphisms) method were evaluated. Dice's coefficient was used for the similarity analysis.
Results: Over 73% studied patients were included in clusters using RFLPs analysis. This data show that nearly 60% of the tuberculosis cases in our area have a recent transmission. Forty per cent of these cases were included in the main cluster. The frequency of tuberculostatic-resistant strains in HIV infected patients was similar to the that of observed in other patients. We did not find correlation between RFLPs clusters and clinical-epidemiological data.
Conclusions: Tuberculosis transmission in HIV-positive patients using RFLPs as molecular marker shows that 60% of the cases are caused by recently acquired strains. We did not find multi-drug resistant strains in our isolates. However due to the high transmissibility of these circulating clones, control disease measures in this group of risk population are required.