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Objective: To assess the prevalence of severe transaminitis precluding tuberculosis (TB) preventive therapy (TPT) initiation for people with HIV (PWH) in a high TB/HIV burden setting., Design/methods: We conducted a secondary analysis of data from a prospective cohort study of PWH with pre-antiretroviral therapy (ART) CD4 + counts 350 cells/μl or less undergoing systematic TB screening from two HIV clinics in Uganda. For this analysis, we excluded patients with culture-confirmed TB and patients without aspartate transaminase (AST) or alanine transaminase (ALT) levels measured within three months of enrollment. We compared the proportion of patients with any transaminitis (AST or ALT greater than one times the upper limit of normal ULN) and severe transaminitis (AST or ALT >3 times ULN) for patients screening negative for TB by symptoms and for those screening negative by C-reactive protein (CRP). We also assessed the proportion of patients with transaminitis by self-reported alcohol consumption., Results: Among 313 participants [158 (50%) women, median age 34 years (IQR 27-40)], 75 (24%) had any transaminitis and six (2%) had severe transaminitis. Of 32 of 313 (10%) who screened negative for TB by symptoms, none had severe transaminitis. In contrast, six-times more PWH screened negative for TB by CRP (194 of 313; 62%), of whom only four (2.1%) had severe transaminitis. Differences in the proportion with any and severe transaminitis according to alcohol consumption were not statistically significant., Conclusion: Prevalence of severe transaminitis was low among PWH without culture-confirmed TB in this setting, and is therefore, unlikely to be a major barrier to scaling-up TPT., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Detection of tuberculosis at the point-of-care (POC) is limited by the low sensitivity of current commercially available tests. We describe a diagnostic accuracy field evaluation of a prototype urine Tuberculosis Lipoarabinomannan Lateral Flow Assay (TB-LAM LFA) in both HIV-positive and HIV-negative patients using fresh samples with sensitivity and specificity as the measures of accuracy. This prototype combines a proprietary concentration system with a sensitive LFA. In a prospective study of 292 patients with suspected pulmonary tuberculosis in Uganda, the clinical sensitivity and specificity was compared against a microbiological reference standard including sputum Xpert MTB/RIF Ultra and solid and liquid culture. TB-LAM LFA had an overall sensitivity of 60% (95%CI 51-69%) and specificity of 80% (95%CI 73-85%). When comparing HIV-positive (N = 86) and HIV-negative (N = 206) patients, there was no significant difference in sensitivity (sensitivity difference 8%, 95%CI -11% to +24%, p = 0.4351) or specificity (specificity difference -9%, 95%CI -24% to +4%, p = 0.2051). Compared to the commercially available Alere Determine TB-LAM Ag test, the TB-LAM LFA prototype had improved sensitivity in both HIV-negative (difference 49%, 95%CI 37% to 59%, p<0.0001) and HIV-positive patients with CD4+ T-cell counts >200cells/μL (difference 59%, 95%CI 32% to 75%, p = 0.0009). This report is the first to show improved performance of a urine TB LAM test for HIV-negative patients in a high TB burden setting. We also offer potential assay refinement solutions that may further improve sensitivity and specificity., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: HR, LI, and BH are employees of Biopromic AB. Biopromic AB is developing a point-of-care TB LAM test similar to the one presented. JTC, BDG, AB, BBL, HVH, VMH, SB, BHW, CB, DB, and AS were employees of Global Good Fund, Intellectual Ventures. BH is also an author on patents in the field of TB immunoassays, “Monoclonal antibody, method, kit and use” (WO2016012449) and “Method for removing inhibitory components” (US20190302115). JTC, BDG, and BHW are authors on a patent in the field of analyte concentration devices, “Device for rapid detection of tuberculosis-lipoarabinomannan (TB-LAM) with enhanced sensitivity” (US10830760). AP is an author on patents in the field of mycobacteria detection, “Novel anti-lam and anti-pim6/lam monoclonal antibodies for diagnosis and treatment of mycobacterium tuberculosis infections” (US20190038747) and “Methods for dual detection and differentiation of infection by mycobactierum tuberculosis complex and nontuberculous mycobacteria” (WO2020018806). None of the disclosed competing interest alter our adherence to PLOS ONE policies on sharing data and materials.

The performance of urine Xpert MTB/RIF Ultra (Xpert Ultra) for pulmonary TB diagnosis is unknown. HIV-positive and HIV-negative adults were enrolled at two health facilities in Kampala, Uganda. We compared the accuracy of urine Xpert Ultra and Determine TB-LAM in reference to sputum-based testing (positive Xpert MTB/RIF or culture), and assessed incremental yield. Urine Xpert Ultra had low sensitivity (17.2%, 95% CI 12.3-23.2) but high specificity (98.1%, 95% CI 94.4-99.6). Sensitivity reached 50.0% (95% CI 28.2-71.8) among HIV-positive patients with CD4 <100 cells/μL. Compared to Determine TB-LAM, urine Xpert Ultra was 9.4% (95% CI 3.8-14.9, P = 0.01) more sensitive, and 17.2% (95% CI 4.5-29.8, P = 0.01) more sensitive among HIV-positive patients. However, the incremental sensitivity of urine Xpert Ultra relative to sputum Xpert MTB/RIF was only 1% (95% CI -0.9 to 2.8). Urine Xpert Ultra could be an alternative for patients with advanced HIV infection unable to produce sputum., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Tuberculosis (TB) risk varies among different HIV subgroups, potentially impacting intensified case finding (ICF) performance. We evaluated the performance of the current ICF algorithm [symptom screening, followed by Xpert MTB/RIF (Xpert) testing] in 2 HIV subgroups and evaluated whether ICF performance could be improved if TB screening was based on C-reactive protein (CRP) concentrations., Methods: We enrolled consecutive adults with CD4 counts ≤350 cells/µL initiating antiretroviral therapy and performed symptom screening, CRP testing using a low-cost point-of-care (POC) assay, and collected sputum for Xpert testing. We compared the yield and efficiency of the current ICF algorithm to POC CRP-based ICF among patients new to HIV care and patients engaged in care., Results: Of 1794 patients, 126/1315 (10%) new patients and 21/479 (4%) engaged patients had Xpert-positive TB. The current ICF algorithm detected ≥98% of all TB cases in both subgroups but required ≥85% of all patients to undergo Xpert testing. POC CRP-based ICF halved the proportion of patients in both subgroups requiring Xpert testing relative to the current ICF algorithm and had lower yield among patients engaged in care [81% vs. 100%, difference -19% (95% confidence interval: -41 to 3)]. Among patients new to care, POC CRP-based ICF had similar yield as the current ICF algorithm [93% vs. 98%, difference -6% (95% confidence interval: -11 to 0)]., Conclusions: Among patients new to care, POC CRP-based screening can improve ICF efficiency without compromising ICF yield, whereas symptom-based screening may be necessary to maximize ICF yield among patients engaged in care.

Background: Gene-expression profiles have been reported to distinguish between patients with and without active tuberculosis (TB), but no prior study has been conducted in the context of TB screening., Methods: We included all the patients (n = 40) with culture-confirmed TB and time-matched controls (n = 80) enrolled between July 2013 and April 2015 in a TB screening study among people living with human immunodeficiency virus (PLHIV) in Kampala, Uganda. We randomly split the patients into training (n = 80) and test (n = 40) datasets. We used the training dataset to derive candidate signatures that consisted of 1 to 5 differentially-expressed transcripts (P ≤ .10) and compared the performance of our candidate signatures with 4 published TB gene-expression signatures, both on the independent test dataset and in 2 external datasets., Results: We identified a novel, 5-transcript signature that met the accuracy thresholds recommended for a TB screening test. On the independent test dataset, our signature had an area under the curve (AUC) of 0.87 (95% confidence interval [CI] 0.72-0.98), with sensitivity of 94% and specificity of 75%. None of the 4 published TB signatures achieved desired accuracy thresholds. Our novel signature performed well in external datasets from both high (AUC 0.81, 95% CI 0.74-0.88) and low (0.81, 95% CI 0.77-0.85) TB burden settings., Conclusions: We identified the first gene-expression signature for TB screening. Our signature has the potential to be translated into a point-of-care test to facilitate systematic TB screening among PLHIV and other high-risk populations., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objectives: In resource-limited settings, mortality in the initial months following antiretroviral therapy (ART) initiation remains unacceptably high. Novel tools to identify patients at highest risk of poor outcomes are needed. We evaluated whether elevated C-reactive protein (CRP) concentrations predict poor outcomes among people living with HIV (PLWH) initiating ART., Methods: We enrolled and followed for 3-months consecutive PLWH with pre-ART CD4 T-cell counts 350 cells/μl or less initiating ART from two HIV clinics in Uganda. Pre-ART CRP concentrations were measured from capillary blood using a point-of-care (POC) assay. After excluding patients with prevalent tuberculosis - the leading cause of HIV death - we measured 3-month mortality rates using Kaplan-Meier curves, used Cox regression to compare differences in survival, and used logistic regression to compare differences in the odds of opportunistic infections, between patients with and without elevated POC CRP (≥8 mg/l)., Results: Of 1293 patients included [median CD4 T-cell count 181 (interquartile range 82-278)], 23 (1.8%) died within 3 months, including 19 of 355 (5.4%) with elevated POC CRP and four of 938 (0.4%) with nonelevated POC CRP. Eighty-six (6.7%) patients were diagnosed with opportunistic infections, including 39 of 355 (11.0%) with elevated POC CRP and 47 of 938 (5.0%) with nonelevated POC CRP. Elevated POC CRP was associated with mortality (adjusted hazard ratio 10.87, 95% confidence interval 3.64-32.47) and opportunistic infection (adjusted odds ratio 1.95, 95% confidence interval 1.23-3.07)., Conclusion: Among PLWH with advanced HIV, elevated pre-ART POC CRP concentrations are associated with early mortality and opportunistic infections. Pre-ART POC CRP testing may reduce mortality by identifying patients at high risk for poor outcomes.

Rationale: The recommended tuberculosis (TB) intensified case finding (ICF) algorithm for people living with HIV (symptom-based screening followed by Xpert MTB/RIF [Xpert] testing) is insufficiently sensitive and results in unnecessary Xpert testing., Objectives: To evaluate whether novel ICF algorithms combining C-reactive protein (CRP)-based screening with urine Determine TB-LAM (TB-LAM), sputum Xpert, and/or sputum culture could improve ICF yield and efficiency., Methods: We compared the yield and efficiency of novel ICF algorithms inclusive of point-of-care CRP-based TB screening and confirmatory testing with urine TB-LAM (if CD4 count ≤100 cells/μl), sputum Xpert, and/or a single sputum culture among consecutive people living with HIV with CD4 counts less than or equal to 350 cells/μl initiating antiretroviral therapy in Uganda., Measurements and Main Results: Of 1,245 people living with HIV, 203 (16%) had culture-confirmed TB including 101 (49%) patients with CD4 counts less than or equal to 100 cells/μl. Compared with the current ICF algorithm, point-of-care CRP-based TB screening followed by Xpert testing had similar yield (56% [95% confidence interval, 49-63] vs. 59% [95% confidence interval, 51-65]) but consumed less than half as many Xpert assays per TB case detected (9 vs. 4). Addition of TB-LAM did not significantly increase diagnostic yield relative to the current ICF algorithm but provided same-day diagnosis for 26% of TB patients with advanced HIV. Addition of a single culture to TB-LAM and Xpert substantially improved ICF yield, identifying 78% of all TB cases., Conclusions: Point-of-care CRP-based screening can improve ICF efficiency among people living with HIV. Addition of TB-LAM and a single culture to Xpert confirmatory testing could enable HIV programs to increase the speed of TB diagnosis and ICF yield.

Background: Symptom-based screening for tuberculosis is recommended for all people living with HIV. This recommendation results in unnecessary Xpert MTB/RIF testing in many individuals living in tuberculosis-endemic areas and thus poor implementation of intensified case finding and tuberculosis preventive therapy. Novel approaches to tuberculosis screening are needed to help achieve global targets for tuberculosis elimination. We assessed the performance of C-reactive protein (CRP) measured with a point-of-care assay as a screening tool for active pulmonary tuberculosis., Methods: For this prospective study, we enrolled adults (aged ≥18 years) living with HIV with CD4 cell count less than or equal to 350 cells per μL who were initiating antiretroviral therapy (ART) from two HIV/AIDS clinics in Uganda. CRP concentrations were measured at study entry with a point-of-care assay using whole blood obtained by fingerprick (concentration ≥10 mg/L defined as screen positive for tuberculosis). Sputum samples were collected for Xpert MTB/RIF testing and culture. We calculated the sensitivity and specificity of point-of-care CRP and WHO symptom-based screening in reference to culture results. We repeated the sensitivity analysis with Xpert MTB/RIF as the reference standard., Findings: Between July 8, 2013, and Dec 15, 2015, 1237 HIV-infected adults were enrolled and underwent point-of-care CRP testing. 60 (5%) patients with incomplete or contaminated cultures were excluded from the analysis. Of the remaining 1177 patients (median CD4 count 165 cells per μL [IQR 75-271]), 163 (14%) had culture-confirmed tuberculosis. Point-of-care CRP testing had 89% sensitivity (145 of 163, 95% CI 83-93) and 72% specificity (731 of 1014, 95% CI 69-75) for culture-confirmed tuberculosis. Compared with WHO symptom-based screening, point-of-care CRP testing had lower sensitivity (difference -7%, 95% CI -12 to -2; p=0·002) but substantially higher specificity (difference 58%, 95% CI 55 to 61; p<0·0001). When Xpert MTB/RIF results were used as the reference standard, sensitivity of point-of-care CRP and WHO symptom-based screening were similar (94% [79 of 84] vs 99% [83 of 84], respectively; difference -5%, 95% CI -12 to 2; p=0·10)., Interpretation: The performance characteristics of CRP support its use as a tuberculosis screening test for people living with HIV with CD4 count less than or equal to 350 cells per μL who are initiating ART. HIV/AIDS programmes should consider point-of-care CRP-based tuberculosis screening to improve the efficiency of intensified case finding and increase uptake of tuberculosis preventive therapy., Funding: National Institutes of Health; President's Emergency Plan for AIDS Relief; University of California, San Francisco, Nina Ireland Program for Lung Health., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

BackgroundThe World Health Organization (WHO) has endorsed the next-generation Xpert MTB/RIF Ultra (Ultra) cartridge, and Uganda is currently transitioning from the older generation Xpert MTB/RIF (Xpert) cartridge to Ultra as the initial diagnostic test for pulmonary tuberculosis (TB). We assessed the diagnostic accuracy of Ultra for pulmonary TB among adults in Kampala, Uganda.MethodsWe sampled adults referred for Xpert testing at two hospitals and a health center over a 12-month period. We enrolled adults with positive Xpert and a random 1:1 sample with negative Xpert results. Expectorated sputum was collected for Ultra, and for solid and liquid culture testing for Xpert-negative patients. We measured sensitivity and specificity of Ultra overall and by HIV status, prior history of TB, and hospitalization, in reference to Xpert and culture results. We also assessed how classification of results in the new "trace" category affects Ultra accuracy.ResultsAmong 698 participants included, 211 (30%) were HIV-positive and 336 (48%) had TB. The sensitivity of Ultra was 90.5% (95% CI 86.8-93.4) and specificity was 98.1% (95% CI 96.1-99.2). There were no significant differences in sensitivity and specificity by HIV status, prior history of TB or hospitalization. Xpert and Ultra results were concordant in 670 (96%) participants, with Ultra having a small reduction in specificity (difference 1.9, 95% CI 0.2 to 3.6, p=0.01). When "trace" results were considered positive for all patients, sensitivity increased by 2.1% (95% CI 0.3 to 3.9, p=0.01) without a significant reduction in specificity (- 0.8, 95% CI - 0.3 to 2.0, p=0.08).ConclusionsAfter 1 year of implementation, Ultra had similar performance to Xpert. Considering "trace" results to be positive in all patients increased case detection without significant loss of specificity. Longitudinal studies are needed to compare the benefit of greater diagnoses to the cost of overtreatment.