Diagnosis and treatment of TB patients with rifampicin resistance detected using Xpert® MTB/RIF in Zimbabwe

Abstract

Setting: In Zimbabwe, there are concerns about the management of tuberculosis (TB) patients with rifampicin (RMP) resistance diagnosed using Xpert(®) MTB/RIF.

Objective: To assess linkages between diagnosis and treatment for these patients in Harare and Manicaland provinces in 2014.

Design: A retrospective cohort study.

Results: Of 20 329 Xpert assays conducted, 90% were successful, 11% detected Mycobacterium tuberculosis and 4.5% showed RMP resistance. Of 77 patients with RMP-resistant TB diagnosed by Xpert, 70% had samples sent to the reference laboratory for culture and drug susceptibility testing (CDST); 53% of the samples arrived. In 21% the samples showed M. tuberculosis growth, and in 17% the DST results were recorded, all of which confirmed RMP resistance. Of the 77 patients, 34 (44%) never started treatment for multidrug-resistant (MDR) TB, with documented reasons being death, loss to follow-up and incorrect treatment. Of the 43 patients who started MDR-TB treatment, 12 (71%) in Harare and 17 (65%) in Manicaland started within 2 weeks of diagnosis.

Conclusion: Xpert has been rolled out successfully in two Zimbabwe provinces. However, the process of confirming CDST for Xpert-diagnosed RMP-resistant TB works poorly, and many patients are either delayed or never initiate MDR-TB treatment. These shortfalls must be addressed at the programmatic level.