Short oral regimens for pulmonary rifampicin-resistant tuberculosis (TB-PRACTECAL): an open-label, randomised, controlled, phase 2B-3, multi-arm, multicentre, non-inferiority trial.

BACKGROUND: Around 500 000 people worldwide develop rifampicin-resistant tuberculosis each year. The proportion of successful treatment outcomes remains low and new treatments are needed. Following an interim analysis, we report the final safety and efficacy outcomes of the TB-PRACTECAL trial, evaluating the safety and efficacy of oral regimens for the treatment of rifampicin-resistant tuberculosis. METHODS: This open-label, randomised, controlled, multi-arm, multicentre, non-inferiority trial was conducted at seven hospital and community sites in Uzbekistan, Belarus, and South Africa, and enrolled participants aged 15 years and older with pulmonary rifampicin-resistant tuberculosis. Participants were randomly assigned, in a 1:1:1:1 ratio using variable block randomisation and stratified by trial site, to receive 36-80 week standard care; 24-week oral bedaquiline, pretomanid, and linezolid (BPaL); BPaL plus clofazimine (BPaLC); or BPaL plus moxifloxacin (BPaLM) in stage one of the trial, and in a 1:1 ratio to receive standard care or BPaLM in stage two of the trial, the results of which are described here. Laboratory staff and trial sponsors were masked to group assignment and outcomes were assessed by unmasked investigators. The primary outcome was the percentage of participants with a composite unfavourable outcome (treatment failure, death, treatment discontinuation, disease recurrence, or loss to follow-up) at 72 weeks after randomisation in the modified intention-to-treat population (all participants with rifampicin-resistant disease who received at least one dose of study medication) and the per-protocol population (a subset of the modified intention-to-treat population excluding participants who did not complete a protocol-adherent course of treatment (other than because of treatment failure or death) and those who discontinued treatment early because they violated at least one of the inclusion or exclusion criteria). Safety was measured in the safety population. The non-inferiority margin was 12%. This trial is registered with ClinicalTrials.gov, NCT02589782, and is complete. FINDINGS: Between Jan 16, 2017, and March 18, 2021, 680 patients were screened for eligibility, of whom 552 were enrolled and randomly assigned (152 to the standard care group, 151 to the BPaLM group, 126 to the BPaLC group, and 123 to the BPaL group). The standard care and BPaLM groups proceeded to stage two and are reported here, post-hoc analyses of the BPaLC and BPaL groups are also reported. 151 participants in the BPaLM group and 151 in the standard care group were included in the safety population, with 138 in the BPaLM group and 137 in the standard care group in the modified intention-to-treat population. In the modified intention-to-treat population, unfavourable outcomes were reported in 16 (12%) of 137 participants for whom outcome was assessable in the BPaLM group and 56 (41%) of 137 participants in the standard care group (risk difference -29·2 percentage points [96·6% CI -39·8 to -18·6]; non-inferiority and superiority p<0·0001). 34 (23%) of 151 participants receiving BPaLM had adverse events of grade 3 or higher or serious adverse events, compared with 72 (48%) of 151 participants receiving standard care (risk difference -25·2 percentage points [96·6% CI -36·4 to -13·9]). Five deaths were reported in the standard care group by week 72, of which one (COVID-19 pneumonia) was unrelated to treatment and four (acute pancreatitis, suicide, sudden death, and sudden cardiac death) were judged to be treatment-related. INTERPRETATION: The 24-week, all-oral BPaLM regimen is safe and efficacious for the treatment of pulmonary rifampicin-resistant tuberculosis, and was added to the WHO guidance for treatment of this condition in 2022. These findings will be key to BPaLM becoming the preferred regimen for adolescents and adults with pulmonary rifampicin-resistant tuberculosis. FUNDING: Médecins Sans Frontières.

A 24-Week, All-Oral Regimen for Rifampin-Resistant Tuberculosis.

BACKGROUND: In patients with rifampin-resistant tuberculosis, all-oral treatment regimens that are more effective, shorter, and have a more acceptable side-effect profile than current regimens are needed. METHODS: We conducted an open-label, phase 2-3, multicenter, randomized, controlled, noninferiority trial to evaluate the efficacy and safety of three 24-week, all-oral regimens for the treatment of rifampin-resistant tuberculosis. Patients in Belarus, South Africa, and Uzbekistan who were 15 years of age or older and had rifampin-resistant pulmonary tuberculosis were enrolled. In stage 2 of the trial, a 24-week regimen of bedaquiline, pretomanid, linezolid, and moxifloxacin (BPaLM) was compared with a 9-to-20-month standard-care regimen. The primary outcome was an unfavorable status (a composite of death, treatment failure, treatment discontinuation, loss to follow-up, or recurrence of tuberculosis) at 72 weeks after randomization. The noninferiority margin was 12 percentage points. RESULTS: Recruitment was terminated early. Of 301 patients in stage 2 of the trial, 145, 128, and 90 patients were evaluable in the intention-to-treat, modified intention-to-treat, and per-protocol populations, respectively. In the modified intention-to-treat analysis, 11% of the patients in the BPaLM group and 48% of those in the standard-care group had a primary-outcome event (risk difference, -37 percentage points; 96.6% confidence interval [CI], -53 to -22). In the per-protocol analysis, 4% of the patients in the BPaLM group and 12% of those in the standard-care group had a primary-outcome event (risk difference, -9 percentage points; 96.6% CI, -22 to 4). In the as-treated population, the incidence of adverse events of grade 3 or higher or serious adverse events was lower in the BPaLM group than in the standard-care group (19% vs. 59%). CONCLUSIONS: In patients with rifampin-resistant pulmonary tuberculosis, a 24-week, all-oral regimen was noninferior to the accepted standard-care treatment, and it had a better safety profile. (Funded by Médecins sans Frontières; TB-PRACTECAL ClinicalTrials.gov number, NCT02589782.).

Optimising recruitment to a late-phase tuberculosis clinical trial: a qualitative study exploring patient and practitioner experiences in Uzbekistan.

BACKGROUND: Addressing the global burden of multidrug-resistant tuberculosis (MDR-TB) requires identification of shorter, less toxic treatment regimens. Médecins Sans Frontières (MSF) is currently conducting a phase II/III randomised controlled clinical trial, to find more effective, shorter and tolerable treatments for people with MDR-TB. Recruitment to the trial in Uzbekistan has been slower than expected; we aimed to study patient and health worker experiences of the trial, examining potential factors perceived to impede and facilitate trial recruitment, as well as general perceptions of clinical research in this context. METHODS: We conducted a qualitative study using maximum variation, purposive sampling of participants. We carried out in-depth interviews (IDIs) and focus group discussions (FGDs) guided by semi-structured topic guides. In December 2019 and January 2020, 26 interviews were conducted with patients, Ministry of Health (MoH) and MSF staff and trial health workers, to explore challenges and barriers to patient recruitment as well as perceptions of the trial and research in general. Preliminary findings from the interviews informed three subsequent focus group discussions held with patients, nurses and counsellors. Focus groups adopted a person-centred design, brainstorming potential solutions to problems and barriers. Interviews and FGDs were audio recorded, translated and transcribed verbatim. Thematic analysis, drawing on constant comparison, was used to analyse the data. RESULTS: Health system contexts may compete with new approaches especially when legislative health regulations or policy around treatment is ingrained in staff beliefs, perceptions and practice, which can undermine clinical trial recruitment. Trust plays a significant role in how patients engage with the trial. Decision-making processes are dynamic and associated with relationship to diagnosis, assimilation of information, previous knowledge or experience and influence of peers and close relations. CONCLUSIONS: This qualitative analysis highlights ways in which insights developed together with patients and healthcare workers might inform approaches towards improved recruitment into trials, with the overall objective of delivering evidence for better treatments.

Operational Research to Inform Programmatic Approaches to the Management of Tuberculosis in Uzbekistan.

Globally, an estimated 10 million people fell ill with tuberculosis (TB) in 2019, a number that has been declining very slowly in recent years [...].

Characteristics and Treatment Outcomes of Patients with Tuberculosis Receiving Adjunctive Surgery in Uzbekistan.

Surgical interventions are performed as an adjunct to pharmacological treatment in Uzbekistan in 10-12% of diagnosed tuberculosis (TB) patients. In this study among patients with respiratory TB who had surgical interventions in Republican Specialized Scientific-Practical Medical Centre of Phthisiology and Pulmonology of Uzbekistan (RSSPMCPP) from January to May 2017, we describe (i) reasons and types of surgical intervention, (ii) post-surgical complications, (iii) histological diagnosis before and after surgery, and (iv) treatment outcomes. There were 101 patients included in the analysis (mean age 36 years; 51% male; 71% lived in rural areas). The main indications for surgical intervention included pulmonary tuberculoma (40%), fibrocavitary, or cavernous pulmonary TB (23%) and massive hemoptysis (20%). Pulmonary resections were the most frequent surgical procedures: segmentectomy (41%), lobectomy or bilobectomy (19%), and combined resection (17%). Ten patients (9%) suffered post-surgery complications. According to histological examination after surgery, TB was confirmed in 81 (80%) patients. For the other 20 patients, the confirmed diagnoses were: lung cancer (n = 6), echinococcosis (n = 5), post-TB fibrosis (n = 5), non-tuberculous pleurisy (n = 2), hamartoma (n = 1), and pneumonia (n = 1). The majority of patients (94%), who underwent surgery, were considered successfully treated. In conclusion, adjunctive surgical therapy can be an option for TB treatment, especially in cases of complicated TB.

Adverse Drug Reactions among Children with Tuberculosis in Tashkent, Uzbekistan, 2019.

The treatment of childhood tuberculosis can be challenging due to the lack of pediatric drug formulations and monitoring of drug-toxicity in routine settings. There are no published studies from Uzbekistan on the adverse drug reactions (ADR) associated with anti-tuberculosis treatment in children. In this study, we aimed to investigate the ADR associated with anti-tuberculosis treatment in children. This was a cohort study using secondary program data of children treated at the city and regional tuberculosis clinics in Tashkent, Uzbekistan. Of the 302 patients evaluated, 135 (44.7%) reported ADR. New tuberculosis was registered in 277 (92%) patients and 262 (87%) had extrapulmonary tuberculosis. Factors associated with ADR included treatment at a regional hospital (adjusted odds ratio, aOR = 1.75; p = 0.026), female sex (aOR = 2.2; p = 0.004), and treatment with second-line drugs (aOR = 8.82; p < 0.001). The most common ADRs were gastrointestinal disorders (28.5%) followed by hepatitis (8.9%) and dermatologic reactions (8.6%). Most of the ADRs were mild (55.6%) or moderate (43.7%), only one child had severe ADR. Patients with the identified risk factors should be closely monitored during the treatment. We also recommend expansion of ADR surveillance throughout the country for more representative data in the future.

Diagnostic Procedures, Diagnoses, and Treatment Outcomes of Patients with Presumptive Tuberculosis Pleural Effusion in Uzbekistan.

Tuberculosis (TB) pleural effusion (TPE) is the second most common manifestation of extrapulmonary TB (EPTB), which remains a great diagnostic challenge worldwide. In Uzbekistan, there has been no formal evaluation of the actual practices of diagnosing and treating TPE. Our cohort study therefore aimed to describe the frequency and types of different diagnostic procedures of TPE during 2017-2018 and assess the association of baseline characteristics and establish diagnostic methods with TB treatment outcomes. In total, 187 patients with presumptive TPE were assessed, and 149 had a confirmed diagnosis of TPE (other diagnoses included cancer n = 8, pneumonia n = 17, and 13 cases were unspecified). TB was bacteriologically confirmed in 22 (14.8%), cytologically confirmed in 64 (43.0%), and histologically confirmed in 16 (10.7%) patients. Hepatitis was the only co-morbidity significantly associated with unsuccessful treatment outcomes (RR 4.8; 95%CI: 1.44-15.98, p value 0.011). Multivariable regression analysis showed that drug-resistant TB was independently associated with unsuccessful TB treatment outcome. (RR 3.83; 95%CI: 1.05-14.02, p value 0.04). Multidisciplinary approaches are required to maximize the diagnostic accuracy of TPE and minimize the chances of misdiagnosis. TPE patients with co-infections and those with drug resistance should be more closely monitored to try and ensure successful TB treatment outcomes.

Incidence Rate and Risk Factors for Tuberculosis among People Living with HIV: A 2015-2017 Cohort from Tashkent, Uzbekistan.

People living with the human immunodeficiency virus (PLHIV) have a higher risk of developing active tuberculosis (TB) disease, and TB remains a major cause of death in PLHIV. Uzbekistan is facing a substantial TB epidemic, which increases the risk of PLHIV developing active TB. Our retrospective cohort study aimed to evaluate the incidence rate and assess the risk factors for developing active TB among PLHIV. We collected secondary data extracted from medical charts of all patients, newly diagnosed at the AIDS Center in Tashkent, during the period of 2015-2017. The incidence rate of TB among PLHIV was 5.1 (95% CI: 4.5-6.0) per 1000 person/month. Adjusted regression analysis showed three major risk factors for TB, namely, being less than 15 years old (hazard ratio (HR) 5.83; 95% CI: 3.24-10.50, p value = 0.001),low CD4 count (adjusted hazard ratio(aHR) 21.0; 95% CI: 9.25-47.7, p value < 0.001), and antiretroviral therapy (ART) interruption/not receiving ART (aHR 5.57; 95% CI: 3.46-8.97 and aHR 6.2; 95% CI: 3.75-10.24, p value < 0.001, respectively) were significantly associated with developing active TB among PLHIV. Our findings indicate that taking prescribed ART without interruptions and maintaining CD4cell counts higher than 320 cells/µL are essential to prevent the development of active TB among PLHIV.

Hospitalizations and Treatment Outcomes in Patients with Urogenital Tuberculosis in Tashkent, Uzbekistan, 2016-2018.

Despite the global shift to ambulatory tuberculosis (TB) care, hospitalizations remain common in Uzbekistan. This study examined the duration and determinants of hospitalizations among adult patients (≥18 years) with urogenital TB (UGTB) treated with first-line anti-TB drugs during 2016-2018 in Tashkent, Uzbekistan. This was a cohort study based on the analysis of health records. Of 142 included patients, 77 (54%) were males, the mean (±standard deviation) age was 40 ± 16 years, and 68 (48%) were laboratory-confirmed. A total of 136 (96%) patients were hospitalized during the intensive phase, and 12 (8%) had hospital admissions during the continuation phase of treatment. The median length of stay (LOS) during treatment was 56 days (Interquartile range: 56-58 days). LOS was associated with history of migration (adjusted incidence rate ratio (aIRR): 0.46, 95% confidence interval (CI): 0.32-0.69, p < 0.001); UGTB-related surgery (aIRR: 1.18, 95% CI: 1.01-1.38, p = 0.045); and hepatitis B comorbidity (aIRR: 3.18, 95% CI: 1.98-5.39, p < 0.001). The treatment success was 94% and it was not associated with the LOS. Hospitalization was almost universal among patients with UGTB in Uzbekistan. Future research should focus on finding out what proportion of hospitalizations were not clinically justified and could have been avoided.

Effectiveness and Safety of a Shorter Treatment Regimen in a Setting with a High Burden of Multidrug-Resistant Tuberculosis.

Treatment of drug-resistant tuberculosis is lengthy, insufficiently effective, and toxic. Since 2016, the World Health Organization has recommended shorter treatment regimens (STR). We assessed effectiveness and predictors of drug adverse events (DAE) among patients treated with STR. There were 95 consecutive rifampicin-resistant patients enrolled in STR in Tashkent between June 2018 and September 2019. Of these, 66.3% were successfully treated, 17.9% suffered failed treatment, 7.4% died, 5.3% were lost to follow-up and 3.2% were not evaluated. No recurrence was identified in 54 patients after 12 months of successful treatment completion. There were 47 reported DAE: the incidence rate was 6.15 DAE per 100 person-months-of-treatment. Any DAE was reported in 38 (40%) patients and grade 3/4 DAE were recorded in 21 (22.1%) patients. Median time to DAE was 101 (interquartile range 64-139) days. The most frequently encountered DAE were gastro-intestinal disorders, followed by hepatotoxicity and ototoxicity. The most commonly offending drug inducing DAE was protionamide. The dose was temporarily interrupted in 55.3% of DAE, reduced in 8.5% of DAE and permanently withdrawn in another 8.5% of DAE. HIV status was the only predictor associated with increased hazard of DAE. In Uzbekistan STR showed moderate effectiveness and safety, although treatment failure was high.

Treatment Compliance of Multidrug Resistant Tuberculosis in Uzbekistan: Does Practice Follow Policy?

Compliance with treatment guidelines is essential to achieve successful outcomes in tuberculosis patients. Thus, we assessed if multidrug-resistant tuberculosis treatment practices from 2012-2018 in Uzbekistan were compliant with national guidelines in terms of regimens prescribed, weight-based drug dosages used, and documentation of treatment changes (such as prolongation of intensive phase, change of drugs, and their reasons) in the treatment card and Consilium form. A total of 1481 patients were included. Of them, only 25% received standardized regimens as per guidelines and the remaining received individualized regimens. There was an increasing trend in using standardized regimens from 2% in 2012 to 44% in 2018. Compliance to recommended weight-based drug dosages was observed in 85% of the patients during the intensive phase and 84% in the continuation phase-ranged 71-91% over the years. Prolongation of the intensive phase was done in 42% of patients. The treatment was changed in 44% of patients during the intensive phase and 34% of patients during the continuation phase. The documentation of treatment changes was suboptimal (42-75%) during the initial years (2012-2014); however, it improved significantly during later years (86-100%). Future research should explore reasons for non-compliance so that the quality of patient care can be improved.

Risk Factors for Unfavorable Treatment Outcomes among the Human Immunodeficiency Virus-Associated Tuberculosis Population in Tashkent City, Uzbekistan: 2013-2017.

Tuberculosis (TB) and human immunodeficiency virus (HIV) co-infection poses a growing clinical challenge. People living with HIV have a higher chance of developing TB, and once the disease has progressed, are at greater risk of having unfavorable TB treatment outcomes. Data on TB treatment outcomes among the HIV-associated TB population in Uzbekistan are limited. Thus, we conducted a cohort study among 808 adult patients with HIV-associated TB registered at the Tashkent TB referral hospital from 2013-2017 to document baseline characteristics and evaluate risk factors for unfavorable TB treatment outcomes. The data were collected from medical records and ambulatory cards. About 79.8% of the study population had favorable treatment outcomes. Antiretroviral therapy (ART) coverage at the admission was 26.9%. Information on CD4-cell counts and viral loads were largely missing. Having extrapulmonary TB (aOR 2.21, 95% CI: 1.38-3.53, p = 0.001), positive sputum smear laboratory results on admission (aOR 1.62, 95% CI: 1.07-2.40), diabetes (aOR 5.16, 95% CI: 1.77-14.98), and hepatitis C (aOR 1.68, 95% CI: 1.14-2.46) were independent risk factors for developing unfavorable TB treatment outcomes. The study findings provide evidence for targeted clinical management in co-infected patients with risk factors. Strengthening the integration of TB/HIV services may improve availability of key data to improve co-infection management.

Trends, Characteristics and Treatment Outcomes of Patients with Drug-Resistant Tuberculosis in Uzbekistan: 2013-2018.

Uzbekistan has a high burden of drug-resistant tuberculosis (TB). Although conventional treatment for multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) has been available since 2013, there has been no systematic documentation about its use and effectiveness. We therefore documented at national level the trends, characteristics, and outcomes of patients with drug-resistant TB enrolled for treatment from 2013-2018 and assessed risk factors for unfavorable treatment outcomes (death, failure, loss to follow-up, treatment continuation, change to XDR-TB regimen) in patients treated in Tashkent city from 2016-2017. This was a cohort study using secondary aggregate and individual patient data. Between 2013 and 2018, MDR-TB numbers were stable between 2347 and 2653 per annum, while XDR-TB numbers increased from 33 to 433 per annum. At national level, treatment success (cured and treatment completed) for MDR-TB decreased annually from 63% to 57%, while treatment success for XDR-TB increased annually from 24% to 57%. On multivariable analysis, risk factors for unfavorable outcomes, death, and loss to follow-up in drug-resistant TB patients treated in Tashkent city included XDR-TB, male sex, increasing age, previous TB treatment, alcohol abuse, and associated comorbidities (cardiovascular and liver disease, diabetes, and HIV/AIDS). Reasons for these findings and programmatic implications are discussed.

Universal Access to Xpert MTB/RIF Testing for Diagnosis of Tuberculosis in Uzbekistan: How Well Are We Doing?

As per national guidelines in Uzbekistan, all presumptive tuberculosis patients should be tested using the Xpert MTB/RIF assay for diagnosing tuberculosis. There is no published evidence how well this is being implemented. In this paper, we report on the Xpert coverage among presumptive tuberculosis patients in 2018 and 2019, factors associated with non-testing and delays involved. Analysis of national aggregate data indicated that Xpert testing increased from 24% in 2018 to 46% in 2019, with variation among the regions: 21% in Tashkent region to 100% in Karakalpakstan. In a cohort (January-March 2019) constituted of 40 randomly selected health facilities in Tashkent city and Bukhara region, there were 1940 patients of whom 832 (43%, 95% confidence interval (CI): 41-45%) were not Xpert-tested. Non-testing was significantly higher in Bukhara region (73%) compared to Tashkent city (28%). In multivariable analysis, patient's age, distance between primary health centre (PHC) and Xpert laboratory, diagnostic capacity and site of PHC were associated with non-testing. The median (interquartile range) duration from date of initial visit to PHC to receiving results was 1 (1-2) day in Tashkent city compared to 3 (1-6) days in Bukhara region (p-value < 0.001). While there is commendable progress, universal access to Xpert testing is not a reality yet.

Treatment Outcomes of Isoniazid-Resistant (Rifampicin Susceptible) Tuberculosis Patients in Uzbekistan, 2017-2018.

Tuberculosis patients "resistant to isoniazid and susceptible to rifampicin (Hr-TB)" remain neglected, despite a high burden and poor outcomes. The World Health Organization (WHO) recommends a 6 month regimen consisting of levofloxacin, rifampicin, ethambutol, and pyrazinamide (LRZE) to treat Hr-TB. In contrast, Uzbekistan uses a 9 month regimen (LRZE plus a second-line injectable in the first 3 months). We aimed to assess the treatment outcomes of this novel regimen among Hr-TB patients treated in two regions of Uzbekistan (Fergana and Bukhara) in 2017-2018. We conducted a cohort study involving secondary analysis of routine surveillance data. Of 132 Hr-TB patients, 105 (80%) were successfully treated. Death was the predominant unsuccessful outcome (13, 10%) followed by "treatment failure" (10, 8%) and "lost to follow-up" (4, 2%). High treatment success is an indicator of the potential effectiveness of the novel regimen and adds to the limited global evidence on this issue. However, the sample size was small and there was no comparison group. Since the study was conducted in two regions of Uzbekistan only, the findings have limited generalizability. We recommend future research using an adequate sample size and an appropriate study design (randomized controlled trial or prospective cohort with a control group receiving the WHO-recommended regimen).

Scaling Up Molecular Diagnostic Tests for Drug-Resistant Tuberculosis in Uzbekistan from 2012-2019: Are We on the Right Track?

Uzbekistan has a large burden of drug-resistant tuberculosis (TB). To deal with this public health threat, the National TB Program introduced rapid molecular diagnostic tests such as Xpert MTB/RIF (Xpert) and line probe assays (LPAs) for first-line and second-line drugs. We documented the scale-up of Xpert and LPAs from 2012-2019 and assessed whether this led to an increase in patients with laboratory-confirmed multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB) and extensively drug-resistant TB (XDR-TB). This was a descriptive study using secondary program data. The numbers of GeneXpert instruments cumulatively increased from six to sixty-seven, resulting in annual assays increasing from 5574 to 107,330. A broader use of the technology resulted in a lower proportion of tests detecting Mycobacterium tuberculosis with half of the positive results showing rifampicin resistance. LPA instruments cumulatively increased from two to thirteen; the annual first-line assays for MDR-TB increased from 2582 to 6607 while second-line assays increased from 1435 in 2016 to 6815 in 2019 with about one quarter to one third of diagnosed patients showing second-line drug resistance. Patient numbers with laboratory-confirmed MDR-TB remained stable (from 1728 to 2060) but there was a large increase in patients with laboratory-confirmed XDR-TB (from 31 to 696). Programmatic implications and ways forward are discussed.

Rapid Tuberculosis Diagnostics Including Molecular First- and Second-Line Resistance Testing Based on a Novel Microfluidic DNA Extraction Cartridge.

Xpert MTB/RIF testing has improved tuberculosis (TB) diagnostics and rifampicin (Rif) resistance testing worldwide. However, it has weaknesses, such as its restriction to Rif resistance testing and the inability to use extracted DNA for further testing. Herein, a holistic diagnostic workflow, including TB detection and resistance testing toward Rif, isoniazid, and important second-line drugs (SLDs), based on a novel microfluidic DNA extraction cartridge (TB-Disk), is presented. DNA from 73 precharacterized sputum samples was extracted with TB-Disk, including 45 clinical and bacteriologically confirmed TB samples, nine TB-negative samples, and 19 sputum samples spiked with twofold dilutions of TB bacteria. The extracted DNA was subjected to further testing with FluoroType MTB (FT-MTB), GenoType MTBDRplus (GT-plus), and GenoType MTBDRsl. A total of 100% (20/20) and 72% (18/25) of smear-positive and smear-negative TB samples were identified as Mycobacterium tuberculosis complex positive. A total of 79% (33/42) of subsequently GT-plus tested samples yielded a valid result. Eight samples were identified as multidrug-resistant TB by GT-plus and further tested for resistance toward SLDs using GenoType MTBDRsl, yielding 75% (6/8) valid results. FT-MTB with cartridge-based DNA extraction (Disk-DNA) and DNA extracted with FluoroLyse yielded similar analytical sensitivities. FT-MTB with Disk-DNA was 100% specific. TB-Disk in combination with FT-MTB enables sensitive TB detection. The Disk-DNA can be further used for screening resistance toward first-line drugs and SLDs.

Outcomes with a shorter multidrug-resistant tuberculosis regimen from Karakalpakstan, Uzbekistan.

BACKGROUND: In 2016, World Health Organization guidelines conditionally recommended standardised shorter 9-12-month regimens for multidrug-resistant (MDR) tuberculosis (TB) treatment. We conducted a prospective study of a shorter standardised MDR-TB regimen in Karakalpakstan, Uzbekistan. METHODS: Consecutive adults and children with confirmed rifampicin-resistant pulmonary TB were enrolled between September 1, 2013 and March 31, 2015; exclusions included prior treatment with second-line anti-TB drugs, and documented resistance to ofloxacin or to two second-line injectable agents. The primary outcome was recurrence-free cure at 1 year following treatment completion. RESULTS: Of 146 enrolled patients, 128 were included: 67 female (52.3%), median age 30.1 (interquartile range 23.8-44.4) years. At the end of treatment, 71.9% (92 out of 128) of patients achieved treatment success, with 68% (87 out of 128) achieving recurrence-free cure at 1 year following completion. Unsuccessful outcomes during treatment included 22 (17.2%) treatment failures with fluoroquinolone-resistance amplification in 8 patients (8 out of 22, 36.4%); 12 (9.4%) lost to follow-up; and 2 (1.5%) deaths. Recurrence occurred in one patient. Fourteen patients (10.9%) experienced serious adverse events. Baseline resistance to both pyrazinamide and ethambutol (adjusted OR 6.13, 95% CI 2.01; 18.63) and adherence <95% (adjusted OR 5.33, 95% CI 1.73; 16.36) were associated with unsuccessful outcome in multivariable logistic regression. CONCLUSIONS: Overall success with a standardised shorter MDR-TB regimen was moderate with considerable treatment failure and amplification of fluoroquinolone resistance. When introducing standardised shorter regimens, baseline drug susceptibility testing and minimising missed doses are critical. High rates globally of pyrazinamide, ethambutol and ethionamide resistance raise questions of continued inclusion of these drugs in shorter regimens in the absence of drug susceptibility testing-confirmed susceptibility.

Accuracy of molecular drug susceptibility testing amongst tuberculosis patients in Karakalpakstan, Uzbekistan.

OBJECTIVES: In this retrospective study, we evaluated the diagnostic accuracy of molecular tests (MT) for the detection of DR-TB, compared to the gold standard liquid-based drug susceptibility testing (DST) in Karakalpakstan. METHODS: A total of 6670 specimens received in the Republican TB No 1 Hospital Laboratory of Karakalpakstan between January and July 2017 from new and retreatment patients were analysed. Samples were tested using Xpert MTB/RIF and line probe assays (LPA) for the detection of mutations associated with resistance. The sensitivity and specificity of MTs were calculated relative to results based on DST. RESULTS: The accuracy of MT for detection of rifampicin resistance was high, with sensitivity and specificity over 98%. However, we observed reduced sensitivity of LPA for detection of resistance; 86% for isoniazid (95% CI 82-90%), 86% for fluoroquinolones (95% CI 68-96%), 70% for capreomycin (95% CI 46-88%) and 23% for kanamycin (95% CI 13-35%). CONCLUSIONS: We show that MTs are a useful tool for rapid and safe diagnosis of DR-TB; however, clinicians should be aware of their limitations. Although detection of rifampicin resistance was highly accurate, our data suggest that resistance mutations circulating in the Republic of Karakalpakstan for other drugs were not detected by the methods used here. This merits further investigation.