ABSTRACT
Background: The implementation of rapid drug susceptibility testing (DST) is a current global priority for TBcontrol. However, data are scarce on patient-relevant outcomes for presumptive diagnosis of drug-resistanttuberculosis (pDR-TB) evaluated under field conditions in high burden countries.Methods: Observational study of pDR-TB patients referred by primary and secondary health units. TB referencecenters addressing DR-TB in five cities in Brazil. Patients age 18 years and older were eligible if pDR-TB, culturepositive results for Mycobacterium tuberculosis and, if no prior DST results from another laboratory were used by aphysician to start anti-TB treatment. The outcome measures were median time from triage to initiating appropriateanti-TB treatment, empirical treatment and, the treatment outcomes.Results: Between February,16th, 2011 and February, 15th, 2012, among 175 pDR TB cases, 110 (63.0%) confirmed TBcases with DST results were enrolled. Among study participants, 72 (65.5%) were male and 62 (56.4%) aged 26 to45 years. At triage, empirical treatment was given to 106 (96.0%) subjects. Among those, 85 were treated with firstline drugs and 21 with second line. Median time for DST results was 69.5 [interquartile - IQR: 35.7111.0] days and,for initiating appropriate anti-TB treatment, the median time was 1.0 (IQR: 041.2) days. Among 95 patients thatwere followed-up during the first 6 month period, 24 (25.3%; IC: 17.5%34.9%) changed or initiated the treatmentafter DST results: 16/29 MDRTB, 5/21 DR-TB and 3/45 DS-TB cases. Comparing the treatment outcome to DS-TBcases, MDRTB had higher proportions changing or initiating treatment after DST results (p = 0.01) and favorableoutcomes (p = 0.07).Conclusions: This study shows a high rate of empirical treatment and long delay for DST results. Strategies tospeed up the detection and early treatment of drug resistant TB should be prioritized.
