50 research outputs found
Rifampicin-resistant tuberculosis in Botswana: barriers and risk factors influencing patient outcomes, case detection, and linkage to effective care and treatment
Background: Botswana reports high treatment success for rifampicin-resistant tuberculosis (RR-TB), but many challenges remain. Case detection is lower than expected and varies by year, and mortality rates are high. Research aims included identifying: factors associated with mortality, access to culture and drug susceptibility testing (DST) for patients at risk of RR-TB, access to first- and second-line DST among RR-TB patients, time to RRTB treatment, and patient and provider experiences with RR-TB management. Methods: Retrospective data (multiple cohorts across 2006-2014) were extracted from Botswana national registers and information systems, with additional data collected by standardized, qualitative interviews (2017). Data analyses (Cox proportional hazards regression, survival and hazards curves, logistic regression) were conducted to describe significant associations. A systematic review and meta-analysis was conducted. Thematic analysis was performed for qualitative research. Results: There was low access (42%) to culture testing among patients at risk of RR-TB (previously-treated TB patients); particularly associated with rural residence and having previous successful TB treatment, compared to previous treatment failure. While confirmation of first-line drug resistance was available for 85% of patients initiating RR-TB treatment, access to second-line DST was poor (24%), impacted by limited in-country laboratory capacity. Genotypic DST by Xpert MTB/RIF at peripheral laboratories was associated with faster time to treatment from diagnosis compared to phenotypic DST at the centralized national lab, 5 versus 22 days (median, p<0.001), consistent with systematic review findings of time to RR-TB treatment. Risk factors for mortality during treatment included unconfirmed RR-TB (aHR 2.9), Pre/XDR-TB (aHR 2.5), HIV positivity without ART (aHR 3.6) and receiving treatment at two (of five) specific facilities (aHR 2.6 and 2.3). Qualitative interviews confirmed inconsistent adherence to national policies and identified additional challenges including frequent medication and reagent stock-outs, misperceptions about disease transmission from both providers and patients, and inadequate national level support for the RR-TB program. Conclusion: Several clinical and demographic factors negatively influencing case detection and RR-TB mortality in Botswana were identified. General health system dysfunction and poor political commitment to the RR-TB program also contributed. Recommendations include increased focus on: early diagnosis through universal DST, consistent access to effective drugs, and overall adherence to policies
Effect of tuberculosis screening and retention interventions on early antiretroviral therapy mortality in Botswana: a stepped-wedge cluster randomized trial.
BACKGROUND: Undiagnosed tuberculosis (TB) remains the most common cause of HIV-related mortality. Xpert MTB/RIF (Xpert) is being rolled out globally to improve TB diagnostic capacity. However, previous Xpert impact trials have reported that health system weaknesses blunted impact of this improved diagnostic tool. During phased Xpert rollout in Botswana, we evaluated the impact of a package of interventions comprising (1) additional support for intensified TB case finding (ICF), (2) active tracing for patients missing clinic appointments to support retention, and (3) Xpert replacing sputum-smear microscopy, on early (6-month) antiretroviral therapy (ART) mortality. METHODS: At 22 clinics, ART enrollees >?12?years old were eligible for inclusion in three phases: a retrospective standard of care (SOC), prospective enhanced care (EC), and prospective EC plus Xpert (EC+X) phase. EC and EC+X phases were implemented as a stepped-wedge trial. Participants in the EC phase received SOC plus components 1 (strengthened ICF) and 2 (active tracing) of the intervention package, and participants in the EC+X phase received SOC plus all three intervention package components. Primary and secondary objectives were to compare all-cause 6-month ART mortality between SOC and EC+X and between EC and EC+X phases, respectively. We used adjusted analyses, appropriate for study design, to control for baseline differences in individual-level factors and intra-facility correlation. RESULTS: We enrolled 14,963 eligible patients: 8980 in SOC, 1768 in EC, and 4215 in EC+X phases. Median age of ART enrollees was 35 and 64% were female. Median CD4 cell count was lower in SOC than subsequent phases (184/?L in SOC, 246/?L in EC, and 241/?L in EC+X). By 6?months of ART, 461 (5.3%) of SOC, 54 (3.2%) of EC, and 121 (3.0%) of EC+X enrollees had died. Compared with SOC, 6-month mortality was lower in the EC+X phase (adjusted hazard ratio, 0.77; 95% confidence interval, 0.61-0.97, p?=?0.029). Compared with EC enrollees, 6-month mortality was similar among EC+X enrollees. CONCLUSIONS: Interventions to strengthen ICF and retention were associated with lower early ART mortality. This new evidence highlights the need to strengthen ICF and retention in many similar settings. Similar to other trials, no additional mortality benefit of replacing sputum-smear microscopy with Xpert was observed. TRIAL REGISTRATION: Retrospectively registered: ClinicalTrials.gov (NCT02538952)
Risk scores for predicting early antiretroviral therapy mortality in sub-Saharan Africa to inform who needs intensification of care: a derivation and external validation cohort study.
BACKGROUND: Clinical scores to determine early (6-month) antiretroviral therapy (ART) mortality risk have not been developed for sub-Saharan Africa (SSA), home to 70% of people living with HIV. In the absence of validated scores, WHO eligibility criteria (EC) for ART care intensification are CD4  37.5 °C (2 points). The same variables plus CD4 < 200/μL (1 point) were included in the CD4-dependent score. Among XPRES enrollees, a CD4-independent score of ≥ 4 would provide 86% sensitivity and 66% specificity, whereas WHO EC would provide 83% sensitivity and 58% specificity. If WHO stage alone was used, sensitivity was 48% and specificity 89%. Among TBFT enrollees, the CD4-independent score of ≥ 4 would provide 95% sensitivity and 27% specificity, whereas WHO EC would provide 100% sensitivity but 0% specificity. Accuracy was similar between CD4-independent and CD4-dependent scores. Categorizing CD4-independent scores into low (< 4), moderate (4-6), and high risk (≥ 7) gave 6-month mortality of 1%, 4%, and 17% for XPRES and 1%, 5%, and 30% for TBFT enrollees. CONCLUSIONS: Sensitivity of the CD4-independent score was nearly twice that of WHO stage in predicting 6-month mortality and could be used in settings lacking CD4 testing to inform ART care intensification. The CD4-dependent score improved specificity versus WHO EC. Both scores should be considered for scale-up in SSA
Derivation and external validation of a risk score for predicting HIV-associated tuberculosis to support case finding and preventive therapy scale-up: A cohort study.
BACKGROUND: Among people living with HIV (PLHIV), more flexible and sensitive tuberculosis (TB) screening tools capable of detecting both symptomatic and subclinical active TB are needed to (1) reduce morbidity and mortality from undiagnosed TB; (2) facilitate scale-up of tuberculosis preventive therapy (TPT) while reducing inappropriate prescription of TPT to PLHIV with subclinical active TB; and (3) allow for differentiated HIV-TB care. METHODS AND FINDINGS: We used Botswana XPRES trial data for adult HIV clinic enrollees collected during 2012 to 2015 to develop a parsimonious multivariable prognostic model for active prevalent TB using both logistic regression and random forest machine learning approaches. A clinical score was derived by rescaling final model coefficients. The clinical score was developed using southern Botswana XPRES data and its accuracy validated internally, using northern Botswana data, and externally using 3 diverse cohorts of antiretroviral therapy (ART)-naive and ART-experienced PLHIV enrolled in XPHACTOR, TB Fast Track (TBFT), and Gugulethu studies from South Africa (SA). Predictive accuracy of the clinical score was compared with the World Health Organization (WHO) 4-symptom TB screen. Among 5,418 XPRES enrollees, 2,771 were included in the derivation dataset; 67% were female, median age was 34 years, median CD4 was 240 cells/μL, 189 (7%) had undiagnosed prevalent TB, and characteristics were similar between internal derivation and validation datasets. Among XPHACTOR, TBFT, and Gugulethu cohorts, median CD4 was 400, 73, and 167 cells/μL, and prevalence of TB was 5%, 10%, and 18%, respectively. Factors predictive of TB in the derivation dataset and selected for the clinical score included male sex (1 point), ≥1 WHO TB symptom (7 points), smoking history (1 point), temperature >37.5°C (6 points), body mass index (BMI) 10) yielded TB prevalence of 1%, 1%, 2%, and 6% in the lowest risk group and 33%, 22%, 26%, and 32% in the highest risk group for XPRES, XPHACTOR, TBFT, and Gugulethu cohorts, respectively. At clinical score ≥2, the number needed to screen (NNS) ranged from 5.0 in Gugulethu to 11.0 in XPHACTOR. Limitations include that the risk score has not been validated in resource-rich settings and needs further evaluation and validation in contemporary cohorts in Africa and other resource-constrained settings. CONCLUSIONS: The simple and feasible clinical score allowed for prioritization of sensitivity and NPV, which could facilitate reductions in mortality from undiagnosed TB and safer administration of TPT during proposed global scale-up efforts. Differentiation of risk by clinical score cutoff allows flexibility in designing differentiated HIV-TB care to maximize impact of available resources
An old warm Jupiter orbiting the metal-poor G-dwarf TOI-5542
We report the discovery of a 1.32−0.10+0.10 MJup planet orbiting on a 75.12 day period around the G3V 10.8−3.6+2.1 Gyr old star TOI-5542 (TIC 466206508; TYC 9086-1210-1). The planet was first detected by the Transiting Exoplanet Survey Satellite (TESS) as a single transit event in TESS Sector 13. A second transit was observed 376 days later in TESS Sector 27. The planetary nature of the object has been confirmed by ground-based spectroscopic and radial velocity observations from the CORALIE and HARPS spectrographs. A third transit event was detected by the ground-based facilities NGTS, EulerCam, and SAAO. We find the planet has a radius of 1.009−0.035+0.036 RJup and an insolation of 9.6−0.8+0.9 S⊕, along with a circular orbit that most likely formed via disk migration or in situ formation, rather than high-eccentricity migration mechanisms. Our analysis of the HARPS spectra yields a host star metallicity of [Fe/H] = −0.21 ± 0.08, which does not follow the traditional trend of high host star metallicity for giant planets and does not bolster studies suggesting a difference among low- and high-mass giant planet host star metallicities. Additionally, when analyzing a sample of 216 well-characterized giant planets, we find that both high masses (4 MJup 10 days) and hot (P 0.1). TOI-5542b is one of the oldest known warm Jupiters and it is cool enough to be unaffected by inflation due to stellar incident flux, making it a valuable contribution in the context of planetary composition and formation studies
Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study
BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223
Implementation of a pragmatic, stepped-wedge cluster randomized trial to evaluate impact of Botswana’s Xpert MTB/RIF diagnostic algorithm on TB diagnostic sensitivity and early antiretroviral therapy mortality
Repeated nebulisation of non-viral CFTR gene therapy in patients with cystic fibrosis:a randomised, double-blind, placebo-controlled, phase 2b trial
Background: Lung delivery of plasmid DNA encoding the CFTR gene complexed with a cationic liposome is a potential treatment option for patients with cystic fibrosis. We aimed to assess the efficacy of non-viral CFTR gene therapy in patients with cystic fibrosis. Methods: We did this randomised, double-blind, placebo-controlled, phase 2b trial in two cystic fibrosis centres with patients recruited from 18 sites in the UK. Patients (aged ≥12 years) with a forced expiratory volume in 1 s (FEV1) of 50–90% predicted and any combination of CFTR mutations, were randomly assigned, via a computer-based randomisation system, to receive 5 mL of either nebulised pGM169/GL67A gene–liposome complex or 0·9% saline (placebo) every 28 days (plus or minus 5 days) for 1 year. Randomisation was stratified by % predicted FEV1 (<70 vs ≥70%), age (<18 vs ≥18 years), inclusion in the mechanistic substudy, and dosing site (London or Edinburgh). Participants and investigators were masked to treatment allocation. The primary endpoint was the relative change in % predicted FEV1. The primary analysis was per protocol. This trial is registered with ClinicalTrials.gov, number NCT01621867. Findings: Between June 12, 2012, and June 24, 2013, we randomly assigned 140 patients to receive placebo (n=62) or pGM169/GL67A (n=78), of whom 116 (83%) patients comprised the per-protocol population. We noted a significant, albeit modest, treatment effect in the pGM169/GL67A group versus placebo at 12 months' follow-up (3·7%, 95% CI 0·1–7·3; p=0·046). This outcome was associated with a stabilisation of lung function in the pGM169/GL67A group compared with a decline in the placebo group. We recorded no significant difference in treatment-attributable adverse events between groups. Interpretation: Monthly application of the pGM169/GL67A gene therapy formulation was associated with a significant, albeit modest, benefit in FEV1 compared with placebo at 1 year, indicating a stabilisation of lung function in the treatment group. Further improvements in efficacy and consistency of response to the current formulation are needed before gene therapy is suitable for clinical care; however, our findings should also encourage the rapid introduction of more potent gene transfer vectors into early phase trials
High Treatment Success Rates Among HIV-Infected Multidrug-Resistant Tuberculosis Patients After Expansion of Antiretroviral Therapy in Botswana, 2006-2013.
BackgroundFew studies have examined multidrug-resistant (MDR) tuberculosis (TB) treatment outcomes among HIV-infected persons after widespread expansion of antiretroviral therapy (ART). We describe MDR-TB treatment outcomes among HIV-infected and HIV-uninfected patients in Botswana after ART expansion.MethodsWe retrospectively reviewed data from patients who started MDR-TB therapy in Botswana during 2006-2013. Multivariable regression models were used to compare treatment outcomes between HIV-infected and HIV-uninfected patients.ResultsWe included 588 MDR-TB patients in the analysis, of whom, 47 (8.0%) and 9 (1.5%) were diagnosed with pre-extensively drug-resistant (XDR)-TB and XDR-TB, respectively. Of the 408 (69.4%) HIV-infected patients, 352 (86.0%) were on ART or started ART during treatment, and median baseline CD4 T-cell count was 234 cells/mm. Treatment success rates were 79.4% and 73.0% among HIV-uninfected and HIV-infected patients, respectively (P = 0.121). HIV-infected patients with CD4 T-cell count <100 cells/mm were more likely to die during treatment compared with HIV-uninfected patients (adjusted risk ratio = 1.890; 95% CI: 1.098 to 3.254).ConclusionsHigh rates of treatment success were achieved with programmatic management of MDR-TB and HIV in Botswana after widespread expansion of ART. However, a 2-fold increase in mortality was observed among HIV-infected persons with baseline CD4 <100 cells/mm compared with HIV-uninfected persons
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High Treatment Success Rates Among HIV-Infected Multidrug-Resistant Tuberculosis Patients After Expansion of Antiretroviral Therapy in Botswana, 2006-2013.
BackgroundFew studies have examined multidrug-resistant (MDR) tuberculosis (TB) treatment outcomes among HIV-infected persons after widespread expansion of antiretroviral therapy (ART). We describe MDR-TB treatment outcomes among HIV-infected and HIV-uninfected patients in Botswana after ART expansion.MethodsWe retrospectively reviewed data from patients who started MDR-TB therapy in Botswana during 2006-2013. Multivariable regression models were used to compare treatment outcomes between HIV-infected and HIV-uninfected patients.ResultsWe included 588 MDR-TB patients in the analysis, of whom, 47 (8.0%) and 9 (1.5%) were diagnosed with pre-extensively drug-resistant (XDR)-TB and XDR-TB, respectively. Of the 408 (69.4%) HIV-infected patients, 352 (86.0%) were on ART or started ART during treatment, and median baseline CD4 T-cell count was 234 cells/mm. Treatment success rates were 79.4% and 73.0% among HIV-uninfected and HIV-infected patients, respectively (P = 0.121). HIV-infected patients with CD4 T-cell count <100 cells/mm were more likely to die during treatment compared with HIV-uninfected patients (adjusted risk ratio = 1.890; 95% CI: 1.098 to 3.254).ConclusionsHigh rates of treatment success were achieved with programmatic management of MDR-TB and HIV in Botswana after widespread expansion of ART. However, a 2-fold increase in mortality was observed among HIV-infected persons with baseline CD4 <100 cells/mm compared with HIV-uninfected persons