Background The Xpert MTB/RIF (Xpert) assay is used globally to rapidly diagnose tuberculosis and resistance to rifampicin. We investigated the frequency and predictors of false-positive findings of rifampicin resistance with Xpert.Methods We did a prospective, observational study of individuals who were enrolled in a Rwandan nationwide diagnostic cohort study (DIAMA trial; NCT03303963). We included patients identified to have rifampicin resistance on initial Xpert testing. We did a repeat Xpert assay and used rpoB Sanger and deep sequencing alongside phenotypic drug susceptibility testing (pDST) to ascertain final rifampicin susceptibility status, with any (hetero)resistant result overriding. We used multivariable logistic regression to assess predictors of false rifampicin resistance on initial Xpert testing, adjusted for HIV status, tuberculosis treatment history, initial Xpert semi-quantitative bacillary load, and initial Xpert probe.

SETTING: In 2005, in response to the increasing prevalence of rifampicin-resistant tuberculosis (RR-TB) and poor treatment outcomes, Rwanda initiated the programmatic management of RR-TB, including expanded access to systematic rifampicin drug susceptibility testing (DST) and standardised treatment.OBJECTIVE: To describe trends in diagnostic and treatment delays and estimate their effect on RR-TB mortality.DESIGN: Retrospective analysis of individual-level data including 748 (85.4%) of 876 patients diagnosed with RR-TB notified to the World Health Organization between 1 July 2005 and 31 December 2016 in Rwanda. Logistic regression was used to estimate the effect of diagnostic and therapeutic delays on RR-TB mortality.RESULTS: Between 2006 and 2016, the median diagnostic delay significantly decreased from 88 days to 1 day, and the therapeutic delay from 76 days to 3 days. Simultaneously, RR-TB mortality significantly decreased from 30.8% in 2006 to 6.9% in 2016. Total delay in starting multidrug-resistant TB (MDR-TB) treatment of more than 100 days was associated with more than two-fold higher odds for dying. When delays were long, empirical RR-TB treatment initiation was associated with a lower mortality.CONCLUSION: The reduction of diagnostic and treatment delays reduced RR-TB mortality. We anticipate that universal testing for RR-TB, short diagnostic and therapeutic delays and effective standardised MDR-TB treatment will further decrease RR-TB mortality in Rwanda.

Objective and methods Worldwide, tuberculosis (TB) is the leading cause of death from a single infectious agent. In many countries, national TB prevalence surveys are the only way to reliably measure the burden of TB disease and can also provide other evidence to inform national efforts to improve TB detection and treatment. Our objective was to synthesise the results and lessons learned from national surveys completed in Africa between 2008 and 2016, to complement a previous review for Asia. Results Twelve surveys completed in Africa were identified: Ethiopia (2010–2011), Gambia (2011–2013), Ghana (2013), Kenya (2015–2016), Malawi (2013–2014), Nigeria (2012), Rwanda (2012), Sudan (2013–2014), Tanzania (2011–2012), Uganda (2014–2015), Zambia (2013–2014) and Zimbabwe (2014). The eligible population in all surveys was people aged ≥15 years who met residency criteria. In total 588 105 individuals participated, equivalent to 82% (range 57–96%) of those eligible. The prevalence of bacteriologically confirmed pulmonary TB disease in those ≥15 years varied from 119 (95% CI 79–160) per 100 000 population in Rwanda and 638 (95% CI 502–774) per 100 000 population in Zambia. The male:female ratio was 2.0 overall, ranging from 1.2 (Ethiopia) to 4.1 (Uganda). Prevalence per 100 000 population generally increased with age, but the absolute number of cases was usually highest among those aged 35–44 years. Of identified TB cases, 44% (95% CI 40–49) did not report TB symptoms during screening and were only identified as eligible for diagnostic testing due to an abnormal chest X‐ray. The overall ratio of prevalence to case notifications was 2.5 (95% CI 1.8–3.2) and was consistently higher for men than women. Many participants who did report TB symptoms had not sought care; those that had were more likely to seek care in a public health facility. HIV prevalence was systematically lower among prevalent cases than officially notified TB patients with an overall ratio of 0.5 (95% CI 0.3–0.7). The two main study limitations were that none of the surveys included people <15 years, and 5 of 12 surveys did not have data on HIV status. Conclusions National TB prevalence surveys implemented in Africa between 2010 and 2016 have contributed substantial new evidence about the burden of TB disease, its distribution by age and sex, and gaps in TB detection and treatment. Policies and practices to improve access to health services and reduce under‐reporting of detected TB cases are needed, especially among men. All surveys provide a valuable baseline for future assessment of trends in TB disease burden.

Background Rwanda conducted a national tuberculosis (TB) prevalence survey to determine the magnitude of TB in the country and determine to what extent the national surveillance system captures all TB cases. In addition we measured the patient diagnostic rate, comparing the measured TB burden data with the routine surveillance data to gain insight into how well key population groups are being detected. Methods A national representative nationwide cross-sectional survey was conducted in 73 clusters in 2012 whereby all enrolled participants (residents aged 15 years and above) were systematically screened for TB by symptoms and chest X-ray (CXR). Those with either clinical symptoms (cough of any duration) and/or CXR abnormalities suggestive of TB disease were requested to provide two sputum samples (one spot and one morning) for smear examination and solid culture. Results Of the 45,058 eligible participants, 43,779 were enrolled in the survey. Participation rate was high at 95.7% with 99.8% of participants undergoing both screening procedures and 99.0% of those eligible for sputum examination submitting at least one sputum sample. Forty cases of prevalent mycobacterium tuberculosis (MTB) and 16 mycobacteria other than tuberculosis (MOTT) cases were detected during the survey. Chest x-ray as screening tool had 3 and 5 times greater predictive odds for smear positive and bacteriological confirmed TB than symptom screening alone respectively. A TB prevalence of 74.1 (95% CI 48.3-99.3) per 100,000 adult population for smear positive TB and 119.3 (95% CI 78.8-PLOS ONE