Introduction:

The emergence of tuberculosis (TB) and multidroresistant strains represents a problem for TB control. The objective was to evaluate the Xpert MTB/RIF (Xpert) in vulnerable groups (VG).

Material and methods:

We studied 82 pulmonary samples with Xpert indication, at the National Reference Laboratory, «Pedro Kourí» Institute, from May to October 2016. Sputum smear (AFB) and culture was performed, according to the laboratory procedures and Xpert according to the manufacturer’s standards. The results of the molecular assay were compared with the culture (detection of Mycobacterium tuberculosis) and proportions method (susceptibility to rifampicin).

Results:

The VG where most cases of TB were diagnosed was HIV positive (nine), followed by those previously treated (eight). Xpert detected TB in 21 cases, of which, eight was AFB negative. There was good agreement between Xpert and culture methods (greater than 92%) and excellent coincidence with the proportions method.

Conclusions:

The Xpert had a positive impact on the timely handling of cases. The excellent correlation between Xpert MTB/RIF and the proportions method demonstrates the utility of the system for the rapid assessment of rifampicin resistance as an indicator of TB - MDR.