ObjectivesBetter outcomes in tuberculosis require new diagnostic and treatment monitoring tools. In this paper we evaluated the utility of a marker of M. tuberculosis viable count, the Molecular Bacterial Load assay (MBLA) for diagnosis and treatment monitoring of tuberculosis in a high burden setting.MethodsPatients with smear positive pulmonary tuberculosis from two sites in Tanzania and one each in Malawi and Mozambique. Sputum samples were taken weekly for the first 12 weeks of treatment and evaluated by MBLA and mycobacterial growth indicator tube method (MGIT).ResultsThe results of high and low positive control samples confirmed inter site reproducibility. Over the 12 weeks of treatment there was a steady decline in the viable bacterial load as measured by the MBLA that corresponds to rise in time to a positive result (TTP) in the Mycobacterial Growth Indicator Tube. Both MBLA and MGIT provided similar time to test negativity. Importantly, as treatment progressed samples in MGIT were increasingly likely to be contaminated, which compromised the acquisition of results but did not affect MBLA samples.ConclusionsMBLA produces a reproducible measure of Mtb viable count comparable to that of MGIT that is not compromised by contamination in a real-world setting. As a molecular test, the results can be available in as little as four hours and could allow health care professionals to identify rapidly patients who are failing therapy.

The STC-NRA method is sensitive for the detection of MTC in sputum. TTD increased with duration of anti-tuberculosis treatment, highlighting the value of this method in monitoring treatment success. The method is simple and inexpensive and, unlike MGIT, does not require technical equipment. The preliminary performance characteristics of the method should be further evaluated in larger studies.

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Background: Tuberculosis (TB), a treatable disease claims over a million lives every year. Accurate rapid diagnosis is crucial for early treatment initiation and prevention of severe disease. Despite over 10 years approval of molecular diagnostics for routine use, an estimated 3 million TB cases go undetected per year. We investigated the barriers and opportunities to maximise uptake and utilization of molecular diagnostics in routine healthcare settings. Methods: We deployed surveys, healthcare facility audits, focus group discussions, in-depth interviews, and policymaker dialogues to unravel factors affecting the uptake and utilization of TB molecular diagnostics in three East African countries. The benchmark was the World Health Organization approved Xpert MTB/RIF and Line Probe Assay (LPA) implemetation at district and regional hospital level respectively. Results: 190 district and county health officers participated in the survey. The survey findings were corroborated by 145 healthcare facility (HCF) audits and 11 policymaker engagement workshops. At 66% coverage, Xpert MTB/RIF fell behind microscopy and clinical diagnosis by 33% and 1% respectively across 190 districts/counties. Stratified by HCF type, Xpert MTB/RIF implementation was 56%, 96% and 95% at district-, regional- and national referral- hospital level. LPA coverage was 4%, 3% below culture across the three countries. Out of 111 HCFs with Xpert MTB/RIF, 37 (33%) utilized it to full capacity, performing ≥8 tests per day of which 51% of these were level five (zonal consultant and national referral) HCFs. Likewise, 75% of LPA test performance was at level five HCFs. Underutilization of Xpert MTB/RIF and LPA was mainly attributed to inadequate- human resource, 22% and utilities, 26% respectively. Absence of the diagnostic services was attributed to under financing. Lack of awareness was second to underfinancing as reason underlying absence of LPA service. Creation of a health tax and decentralising collection and management of this tax to district/county level was proposed by policymakers as means to boost domestic financing for uptake of health technologies. Conclusion Our findings show higher uptake and utilization of molecular and other diagnostics at tertiary- than primary-secondary- level HCFs. Innovative implementation models to ensure quality access at lower level HCFs are urgently needed.