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Background: Estimation of prevalence and diagnostic test accuracy in tuberculosis (TB) prevalence surveys suffer from reference standard and verification biases. The former is attributed to the imperfect reference test used to bacteriologically confirm TB disease. The latter occurs when only the participants screening positive for any TB-compatible symptom or chest X-ray abnormality are selected for bacteriological testing (verification). Bayesian latent class analysis (LCA) alleviates the reference standard bias but suffers verification bias in TB prevalence surveys. This work aims to identify best-practice approaches to simultaneously alleviate the reference standard and verification biases in the estimates of pulmonary TB prevalence and diagnostic test performance in TB prevalence surveys., Methods: We performed a secondary analysis of 9869 participants aged ≥15 years from a community-based multimorbidity screening study in a rural district of KwaZulu-Natal, South Africa (Vukuzazi study). Participants were eligible for bacteriological testing using Xpert Ultra and culture if they reported any cardinal TB symptom or had an abnormal chest X-ray finding. We conducted Bayesian LCA in five ways to handle the unverified individuals: (i) complete-case analysis, (ii) analysis assuming the unverified individuals would be negative if bacteriologically tested, (iii) analysis of multiply-imputed datasets with imputation of the missing bacteriological test results for the unverified individuals using multivariate imputation via chained equations (MICE), and simultaneous imputation of the missing bacteriological test results in the analysis model assuming the missing bacteriological test results were (iv) missing at random (MAR), and (v) missing not at random (MNAR). We compared the results of (i)-(iii) to the analysis based on a composite reference standard (CRS) of Xpert Ultra and culture. Through simulation with an overall true prevalence of 2.0%, we evaluated the ability of the models to alleviate both biases simultaneously., Results: Based on simulation, Bayesian LCA with simultaneous imputation of the missing bacteriological test results under the assumption that the missing data are MAR and MNAR alleviate the reference standard and verification biases. CRS-based analysis and Bayesian LCA assuming the unverified are negative for TB alleviate the biases only when the true overall prevalence is <3.0%. Complete-case analysis produced biased estimates. In the Vukuzazi study, Bayesian LCA with simultaneous imputation of the missing bacteriological test results under the MAR and MNAR assumptions produced overall PTB prevalence of 0.9% (95% Credible Interval (CrI): 0.6-1.9) and 0.7% (95% CrI: 0.5-1.1) respectively alongside realistic estimates of overall diagnostic test sensitivity and specificity with substantially overlapping 95% CrI. The CRS-based analysis and Bayesian LCA assuming the unverified were negative for TB produced 0.7% (95% CrI: 0.5-0.9) and 0.7% (95% CrI: 0.5-1.2) overall PTB prevalence respectively with realistic estimates of overall diagnostic test sensitivity and specificity. Unlike CRS-based analysis, Bayesian LCA of multiply-imputed data using MICE mitigates both biases., Conclusion: The findings demonstrate the efficacy of these advanced techniques in alleviating the reference standard and verification biases, enhancing the robustness of community-based screening programs. Imputing missing values as negative for bacteriological tests is plausible under realistic assumptions., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Keter et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: In low-resource settings, anaemia is a very common condition. Identification of anaemia aetiologies remains challenging due to the lack of diagnostic tools and expertise. We aimed to improve anaemia diagnostics using peripheral blood smear (PBS) with remote interpretation in people living with HIV (PLHIV) with moderate to severe anaemia., Methods: We conducted a prospective study nested within the Kilombero and Ulanga Antiretroviral Cohort, including non-pregnant PLHIV aged ≥18 years presenting with moderate (haemoglobin 7.0-9.9 g/dl) or severe (<7.0 g/dl) anaemia at any visit from January 2019 to December 2020. For each participant, ten PBS images, full blood count and clinical details were shared with a haematologist for remote interpretation (enhanced care). Identification of anaemia etiologies and potential impact on treatment was compared between enhanced and standard care., Results: Among 400 PLHIV with moderate to severe anaemia, 349 (87%) were female, median age was 40 years (interquartile range (IQR) 35-46)), 65 (17%) had a body mass index <18.5 kg/m2, 215 (54%) had HIV WHO stage III/IV, 79 (20%) had a CD4 cell count <200 cells/μl and 317 (89%) had HIV viral load <100 copies/ml. Severe anaemia was diagnosed in 84 (21%). Suspected multiple aetiologies were documented more frequently by enhanced care compared to standard care 267 (67%) vs 20 (5%); p<0.001. Suspected iron deficiency was the most frequent aetiology (n = 337; 84%), followed by chronic disease (n = 199; 50%), folate/vitamin B12 deficiency (n = 78; 20%) and haemoglobinopathy (n = 83; 21%). In 272 participants (68%), enhanced care revealed additional clinically relevant findings with impact on the treatment recommendation., Conclusion: Remote interpretation of PBS combined with clinical information and blood cell count results can provide insights to the suspected aetiological diagnosis of moderate and severe anaemia in rural low-resource settings and impact specific treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Anton-Vazquez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Increased body weight is an important risk factor for cardiovascular disease and is increasingly reported as a health problem in people living with HIV (PLHIV). There is limited data from rural sub-Saharan Africa, where malnutrition usually presents with both over- and undernutrition. We aimed to determine the prevalence and risk factors of underweight and overweight/obesity in PLHIV enrolled in a cohort in rural Tanzania before the introduction of integrase inhibitors., Methods: This nested study of the prospective Kilombero and Ulanga Antiretroviral Cohort included adults aged ≥19 years initiated on antiretroviral therapy between 01/2013 and 12/2018 with follow-up through 06/2019. Body Mass Index (BMI) was classified as underweight (<18.5 kg/m2), normal (18.5-24.9 kg/m2), or overweight/obese (≥25.0 kg/m2). Stratified piecewise linear mixed models were used to assess the association between baseline characteristics and follow-up BMI. Cox proportional hazard models were used to assess the association between time-updated BMI and death/loss to follow-up (LTFU)., Results: Among 2,129 patients, 22,027 BMI measurements (median 9 measurements: interquartile range 5-15) were analysed. At baseline, 398 (19%) patients were underweight and 356 (17%) were overweight/obese. The majority of patients were female (n = 1249; 59%), and aged 35-44 years (779; 37%). During the first 9 months, for every three additional months on antiretroviral therapy, BMI increased by 2% (95% confidence interval 1-2%, p<0.0001) among patients underweight at baseline and by 0.7% (0.5-0.6%, p<0.0001) among participants with normal BMI. Over a median of 20 months of follow-up, 107 (5%) patients died and 592 (28%) were LTFU. Being underweight was associated with >2 times the hazard of death/LTFU compared to participants with normal BMI., Conclusion: We found a double burden of malnutrition, with underweight being an independent predictor of mortality. Monitoring and measures to address both states of malnutrition among PLHIV should be integrated into routine HIV care., Competing Interests: I have read the journal’s policy and the author of this manuscript has the following competing interests: Emilio Letang is a full-time employee ViiV Healthcare since May 2021. This does not alter our adherence to PLOS ONE policies on sharing data and materials. Other authors have declared that no competing interests exist., (Copyright: © 2023 Kalinjuma et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Ritonavir-boosted protease inhibitors (bPI) in people living with HIV (PLWH) have been associated with renal impairment. Limited data are available from rural sub-Saharan Africa., Methods: Using data from the Kilombero and Ulanga Antiretroviral Cohort Study (KIULARCO) in rural Tanzania from 2005-01/2020, we assessed the prevalence of renal impairment (estimated glomerular filtration rate <60 mL/min/1.73m2) at the time of switch from first-line antiretroviral treatment (ART) to bPI-regimen and the incidence of renal impairment on bPI. We assessed risk factors for renal impairment using logistic and Cox regression models., Results: Renal impairment was present in 52/687 PLWH (7.6%) at the switch to bPI. Among 556 participants with normal kidney function at switch, 41 (7.4%) developed renal impairment after a median time of 3.5 (IQR 1.6-5.1) years (incidence 22/1,000 person-years (95%CI 16.1-29.8)). Factors associated with renal impairment at switch were older age (adjusted odds ratio (aOR) 1.55 per 10 years; 95%CI 1.15-2.11), body mass index (BMI) <18.5 kg/m2 (aOR 2.80 versus ≥18kg/m2; 95%CI 1.28-6.14) and arterial hypertension (aOR 2.33; 95%CI 1.03-5.28). The risk of renal impairment was lower with increased duration of ART use (aOR 0.78 per one-year increase; 95%CI 0.67-0.91). The renal impairment incidence under bPI was associated with older age (adjusted hazard ratio 2.01 per 10 years; 95%CI 1.46-2.78)., Conclusions: In PLWH in rural sub-Saharan Africa, prevalence and incidence of renal impairment among those who were switched from first-line to bPI-regimens were high. We found associations between renal impairment and older age, arterial hypertension, low BMI and time on ART., Competing Interests: The authors have declared that no competing interests exist.

Background: Dyslipidemia is a leading risk factor for atherosclerotic cardiovascular disease. There are few published epidemiological data regarding dyslipidemia in Africa. We determined full lipid and apolipoprotein profiles and investigated factors associated with lipid levels in urban and rural populations of north-western Tanzania and southern Uganda., Methods: We conducted a cross-sectional survey of randomly-selected, community-dwelling adults (≥18yrs) including five strata per country: one municipality, two district towns and two rural areas. Participants were interviewed and examined using the World Health Organization STEPwise survey questionnaire. Serum levels of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and apolipoproteins were measured. Factors associated with mean lipid levels were assessed by multivariable linear regression. Framingham 10-year cardiovascular risk scores were calculated with and without lipids., Results: One-third of adults in the study population had dyslipidemia. Low high-density lipoprotein cholesterol affected 32-45% of rural adults. High total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B were found in <15% of adult population in all strata, but were more common in urban adults. Factors independently associated with higher mean low-density lipoprotein cholesterol and apolipoprotein B were female gender, older age, higher education, higher income, obesity, and hypertension. Framingham cardiovascular risk scores with and without lipids yielded similar results and 90% of study subjects in all strata were classified as "low risk". Among older adults (>55 years), 30% were classified as "high" or "very high" risk., Conclusions: Dyslipidemias are common among adults in north-western Tanzania and southern Uganda affecting one third of adult population. Overall, cardiovascular risk scores are low but high risk scores are common with older adults. Health services designed and equipped to diagnose and treat dyslipidemia are urgently needed., Competing Interests: The authors have declared that no competing interests exist.

Introduction: For HIV-positive individuals on antiretroviral therapy (ART), the World Health Organization (WHO) recommends routine viral load (VL) monitoring. We report on the cascade of care in individuals with unsuppressed VL after introduction of routine VL monitoring in a district in Lesotho., Materials and Methods: In Butha-Buthe district 12 clinics (11 rural, 1 hospital) send samples for VL testing to the district laboratory. We included data from patients aged ≥15 years from Dec 1, 2015 to November 1, 2018. As per WHO guidelines VL <1000 copies/mL are considered suppressed, those ≥1000copies/mL unsuppressed. Patients with unsuppressed VL receive adherence counseling and follow-up VL within 8-12 weeks. Two consecutively unsuppressed VLs should trigger switch to second-line ART. For analysis of the VL monitoring cascade we defined care to be "according to guidelines" if patients with unsuppressed VL received a follow-up VL within <180 days and follow-up VL was either re-suppressed, or again unsuppressed and the individual was switched to second-line within 90 days., Results: For 9,949 individuals 24,948 VL tests were available. The majority were female (73%), median age 41 years (interquartile range 33-52), and 58% seen at rural clinics. Overall, 25% (260/1028) of individuals were managed according to guidelines: 40% (410/1028) had a follow-up VL within 180 days of their initial unsuppressed VL and 25% (260/1028) of those either re-suppressed or switched to second-line within 90 days. Female patients were more likely to have a follow-up VL done, (p = 0.015). In rural clinics rates of two consecutively unsuppressed VLs were higher than in the hospital (64% vs. 44%, p<0.001), and rural clinics were less likely to switch these patients to second-line (35% vs. 66%, p<0001)., Conclusions: Our data show that in a real-life setting availability of routine VL monitoring may not be exploited to its potential. A lack of timely follow-up after a first unsuppressed VL and reluctance to switch patients with confirmed virological failure, reduce the benefit of VL monitoring, i.e. in the rural clinics. Future studies will have to assess models of care which ensure that VL results are met with an action and make use of scalable innovative approaches., Competing Interests: The authors have declared that no competing interests exist.

Objectives: Our objectives were to describe trends in enrolment and clinical outcomes in the open, prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) in the Morogoro region of southern Tanzania, and identify strengths and areas for improvement in the care of HIV-positive individuals in rural Tanzania., Methods: We included adults (≥15 years) and children (<15 years) enrolled in the cohort in 2005-2014. The cohort underwent significant changes from autumn 2012 to optimise care. We evaluated mortality and loss to follow-up (LTFU) using competing risks methods, ART usage, opportunistic infections (OI), co-infections and laboratory abnormalities., Results: Overall, 7010 adults and 680 children were enrolled; enrolment peaked in 2008 but has increased steadily since 2011. Among adults (65% female; median age 37 [interquartile range 31-45] years), the proportion referred from hospital wards quadrupled in 2013-14 versus earlier years. 653 (9%) adults died and 2648 (38%) were LTFU; the five-year cumulative probabilities of death and LTFU were 10.3% and 44.0%, respectively. Among children, 69 (10%) died and 225 (33%) were LTFU. The corresponding five-year probabilities were 12.1% and 39.6%. Adult ART use (regardless of eligibility) increased from 5% in 2005 to 89% in 2014 (similarly among children), with 9% on second-line therapy in 2014 (17% of children). OI diagnoses increased over time; tuberculosis prevalence at enrolment quadrupled from 6% in 2011 to 26% in 2014. The proportion of newly-enrolled participants assessed for laboratory abnormalities peaked at nearly 100% in 2014 (from a minimum of 24%), yet abnormality prevalences remained fairly constant., Conclusions: In this cohort, ART usage improved dramatically and is approaching targets of 90%. Improved screening led to increases in detection of OIs and laboratory abnormalities, suggesting that a large number of these co-morbidities previously went undetected and untreated. Further work will address the high LTFU rates and implications for mortality estimates, and the management and outcomes of co-morbidities.