Compliance of drug-resistant tuberculosis treatment regimens with drug susceptibility testing results and its association with treatment outcomes in Georgia

Background: Georgia has countrywide drug susceptibility testing (DST) coverage, but it has never been determined what proportion of drug-resistant tuberculosis (DR-TB) patients receive treatment in compliance with the DST profile and whether this compliance is associated with the treatment outcome. Objective: The aim of the study was to determine the extent of treatment adjustment and its association with treatment outcomes among DR-TB patients in Georgia. Methods: A retrospective cohort study was conducted among 670 DR-TB patients aged 18 years and older, from the 2015 and 2016 cohorts. Results: The initially prescribed treatment regimens of 319 (47.6%) DR-TB cases required adjustment. Of these, in 137 (42.9%) cases the regimen was completely adjusted and in 182 (57.0%) cases it was not completely adjusted: in 33 (33/182) cases the regimen was only partially adjusted and in 149 (149/182) cases it was not adjusted at all. Analysis shows that complete adjustment of treatment is significantly associated with successful treatment outcomes. Conclusion: For successful outcomes, all DR-TB treatment regimens, including resistant drug(s), should be adjusted based on the DST profile, regardless of the type of resistance, the number or type of resistant drug(s), and new or repurposed drugs being included in the regimen.