Implementing a chest X-ray artificial intelligence tool to enhance tuberculosis screening in India: Lessons learned.

Artificial Intelligence (AI) based chest X-ray (CXR) screening for tuberculosis (TB) is becoming increasingly popular. Still, deploying such AI tools can be challenging due to multiple real-life barriers like software installation, workflow integration, network connectivity constraints, limited human resources available to interpret findings, etc. To understand these challenges, PATH implemented a TB REACH active case-finding program in a resource-limited setting of Nagpur in India, where an AI software device (qXR) intended for TB screening using CXR images was used. Eight private CXR laboratories that fulfilled prerequisites for AI software installation were engaged for this program. Key lessons about operational feasibility and accessibility, along with the strategies adopted to overcome these challenges, were learned during this program. This program also helped to screen 10,481 presumptive TB individuals using informal providers based on clinical history. Among them, 2,303 individuals were flagged as presumptive for TB by a radiologist or by AI based on their CXR interpretation. Approximately 15.8% increase in overall TB yield could be attributed to the presence of AI alone because these additional cases were not deemed presumptive for TB by radiologists, but AI was able to identify them. Successful implementation of AI tools like qXR in resource-limited settings in India will require solving real-life implementation challenges for seamless deployment and workflow integration.

Plasma drug concentrations of 4-drug fixed-dose combination regimen and its efficacy for treatment of pulmonary tuberculosis under National Tuberculosis Elimination Programme: A prospective pilot study.

BACKGROUND: The thrice weekly dosing regimen of DOTS has shown low rifampicin plasma concentrations as an independent risk factor for unfavourable tuberculosis (TB) outcome. With introduction of daily regimen using fixed dose combinations (FDC) under National Tuberculosis Elimination Programme (NTEP) the existence of suboptimal plasma levels of first-line antitubercular drugs and its clinical significance remain poorly understood. METHOD: We included a prospective cohort of newly diagnosed pulmonary tuberculosis (PTB) patients receiving 4-FDC daily regimen under NTEP. Plasma concentration at 2 hours (C2h) of each drug was determined after two weeks of treatment using liquid chromatography (LCMS/MS) developed by us. TB card and laboratory reports were reviewed for baseline characteristics and clinical status at 2, 4 and 6 months after the initiation of treatment. At a 1 year follow-up, therapy failure was defined as death or a relapse of tuberculosis. RESULTS: Among 40 PTB patients, the C2h post dose plasma concentrations of H, R and E were suboptimal in 25%, 60% and 10% respectively. The C2h of H, R, Z and E were respectively 4.2 ± 2.0, 7.3 ± 2.8, 39.2 ± 8.8 and 3.5 ± 1.2 µg/ml; 60% of the patients had suboptimal plasma concentrations and commonly it was observed with H and R. C2h were lower than expected for at least two drugs i.e. H and R in 25% (10/40) of the patients. Plasma concentration of isoniazid and rifampicin has always been considered important for microbiological response and treatment outcome and low concentrations has been associated with poor treatment response. These patients may require a two year follow up and critical evaluation for prevention of MDR-TB. However, all the TB patients were cured and none of them had recurrence within one year follow up. CONCLUSIONS: All the pulmonary TB patients administering 4-FDC daily regimen under programmatic settings were cured despite the suboptimal levels of isoniaizd and rifampicin. All the patients achieved pyrazinamide plasma levels and probably this could be the reason behind favourable outcome. Further study is required on large sample size with various subset of population to understand the need of therapeutic drug monitoring.

Tuberculosis Pathways to Care and Transmission of Multidrug Resistance in India.

Rationale: India is experiencing a regional increase in cases of multidrug-resistant tuberculosis (MDR-TB). Objectives: Given the complexity of MDR-TB diagnosis and care, we sought to address key knowledge gaps in MDR risk factors, care delays, and drivers of delay to help guide disease control. Methods: From January 2018 to September 2019, we conducted interviews with adults registered with the National TB Elimination Program for MDR (n = 128) and non-MDR-TB (n = 269) treatment to quantitatively and qualitatively study care pathways. We collected treatment records and GeneXpert-TB/RIF diagnostic reports. Measurements and Main Results: MDR-TB was associated with young age and crowded residence. GeneXpert rifampicin resistance diversity was measured at 72.5% Probe E. Median time from symptom onset to diagnosis of MDR was 90 days versus 60 days for non-MDR, Wilcoxon P < 0.01. Delay decreased by a median of 30 days among non-MDR patients with wider access to GeneXpert, Wilcoxon P = 0.02. Pathways to care were complex, with a median (interquartile range) of 4 (3-5) and 3 (2-4) encounters for MDR and non-MDR, respectively. Of patients with MDR-TB, 68% had their first encounter in the private sector, and this was associated with a larger number of subsequent healthcare encounters and catastrophic expenditure. Conclusions: The association of MDR with young age, crowding, and low genotypic diversity raises concerns of ongoing MDR transmission fueled by long delays in care. Delays are decreasing with GeneXpert use, suggesting the need for routine use in presumptive TB. Qualitatively, we identify the need to improve patient retention in the National TB Elimination Program and highlight patients' trust relationship with private providers.

Has introduction of rapid drug susceptibility testing at diagnosis impacted treatment outcomes among previously treated tuberculosis patients in Gujarat, India?

BACKGROUND: Revised National TB Control Programme (RNTCP) in India recommends that all previously-treated TB (PT) patients are offered drug susceptibility testing (DST) at diagnosis, using rapid diagnostics and screened out for rifampicin resistance before being treated with standardized, eight-month, retreatment regimen. This is intended to improve the early diagnosis of rifampicin resistance and its appropriate management and improve the treatment outcomes among the rest of the patients. In this state-wide study from Gujarat, India, we assess proportion of PT patients underwent rapid DST at diagnosis and the impact of this intervention on their treatment outcomes. METHODS: This is a retrospective cohort study involving review of electronic patient-records maintained routinely under RNTCP. All PT patients registered for treatment in Gujarat during January-June 2013 were included. Information on DST and treatment outcomes were extracted from 'presumptive DR-TB patient register' and TB treatment register respectively. We performed a multivariate analysis to assess if getting tested is independently associated with unfavourable outcomes (death, loss-to-follow-up, failure, transfer out). RESULTS: Of 5,829 PT patients, 5306(91%) were tested for drug susceptibility with rapid diagnostics. Overall, 71% (4,113) TB patients were successfully treated - 72% among tested versus 60% among non-tested. Patients who did not get tested at diagnosis had a 34% higher risk of unsuccessful outcomes as compared to those who got tested (aRR - 1.34; 95% CI 1.20-1.50) after adjusting for age, sex, HIV status and type of TB. Unfavourable outcomes (particularly failure and switched to category IV) were higher among INH-resistant patients (39%) as compared to INH-sensitive (29%). CONCLUSION: Offering DST at diagnosis improved the treatment outcomes among PT patients. However, even among tested, treatment outcomes remained suboptimal and were related to INH resistance and high loss-to-follow-up. These need to be addressed urgently for further progress.

Tuberculosis management practices of private practitioners in Pune municipal corporation, India.

BACKGROUND: Private Practitioners (PP) are the primary source of health care for patients in India. Limited representative information is available on TB management practices of Indian PP or on the efficacy of India's Revised National Tuberculosis Control Programme (RNTCP) to improve the quality of TB management through training of PP. METHODS: We conducted a cross-sectional survey of a systematic random sample of PP in one urban area in Western India (Pune, Maharashtra). We presented sample clinical vignettes and determined the proportions of PPs who reported practices consistent with International Standards of TB Care (ISTC). We examined the association between RNTCP training and adherence to ISTC by calculating odds ratios and 95% confidence intervals. RESULTS: Of 3,391 PP practicing allopathic medicine, 249 were interviewed. Of these, 55% had been exposed to RNTCP. For new pulmonary TB patients, 63% (158/249) of provider responses were consistent with ISTC diagnostic practices, and 34% (84/249) of responses were consistent with ISTC treatment practices. However, 48% (120/249) PP also reported use of serological tests for TB diagnosis. In the new TB case vignette, 38% (94/249) PP reported use of at least one second line anti-TB drug in the treatment regimen. RNTCP training was not associated with diagnostic or treatment practices. CONCLUSION: In Pune, India, despite a decade of training activities by the RNTCP, high proportions of providers resorted to TB serology for diagnosis and second-line anti-TB drug use in new TB patients. Efforts to achieve universal access to quality TB management must account for the low quality of care by PP and the lack of demonstrated effect of current training efforts.