1
|
Chen SY, Wu AY, Lunde R, Lai JJ. Osmotic Processor for Enabling Sensitive and Rapid Biomarker Detection via Lateral Flow Assays. Front Bioeng Biotechnol 2022; 10:884271. [PMID: 35721843 PMCID: PMC9199386 DOI: 10.3389/fbioe.2022.884271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Urine is an attractive biospecimen for in vitro diagnostics, and urine-based lateral flow assays are low-cost devices suitable for point-of-care testing, particularly in low-resource settings. However, some of the lateral flow assays exhibit limited diagnostic utility because the urinary biomarker concentration is significantly lower than the assay detection limit, which compromises the sensitivity. To address the challenge, we developed an osmotic processor that statically and spontaneously concentrated biomarkers. The specimen in the device interfaces with the aqueous polymer solution via a dialysis membrane. The polymer solution induces an osmotic pressure difference that extracts water from the specimen, while the membrane retains the biomarkers. The evaluation demonstrated that osmosis induced by various water-soluble polymers efficiently extracted water from the specimens, ca. 5–15 ml/h. The osmotic processor concentrated the specimens to improve the lateral flow assays’ detection limits for the model analytes—human chorionic gonadotropin and SARS-CoV-2 nucleocapsid protein. After the treatment via the osmotic processor, the lateral flow assays detected the corresponding biomarkers in the concentrated specimens. The test band intensities of the assays with the concentrated specimens were very similar to the reference assays with 100-fold concentrations. The mass spectrometry analysis estimated the SARS-CoV-2 nucleocapsid protein concentration increased ca. 200-fold after the osmosis. With its simplicity and flexibility, this device demonstrates a great potential to be utilized in conjunction with the existing lateral flow assays for enabling highly sensitive detection of dilute target analytes in urine.
Collapse
Affiliation(s)
- Sheng-You Chen
- Department of Mechanical Engineering, University of Washington, Seattle, WA, United States
| | - Abe Y. Wu
- Department of Bioengineering, University of Washington, Seattle, WA, United States
| | - Ruby Lunde
- Department of Bioengineering, University of Washington, Seattle, WA, United States
| | - James J. Lai
- Department of Bioengineering, University of Washington, Seattle, WA, United States
- *Correspondence: James J. Lai,
| |
Collapse
|
2
|
Yin X, Ye QQ, Wu KF, Zeng JY, Li NX, Mo JJ, Huang PY, Xie LM, Xie LY, Guo XG. Diagnostic value of Lipoarabinomannan antigen for detecting Mycobacterium tuberculosis in adults and children with or without HIV infection. J Clin Lab Anal 2022; 36:e24238. [PMID: 35034374 PMCID: PMC8842169 DOI: 10.1002/jcla.24238] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/05/2021] [Accepted: 01/01/2022] [Indexed: 11/16/2022] Open
Abstract
Objectives Even today, tuberculosis (TB) remains a leading public health problem; yet, the current diagnostic methods still have a few shortcomings. Lipoarabinomannan (LAM) provides an opportunity for TB diagnosis, and urine LAM detection seems to have a promising and widely applicable prospect. Design or methods Four databases were systematically searched for eligible studies, and the quality of the studies was evaluated using the quality assessment of diagnostic accuracy studies‐2 (QUADAS‐2). Graphs and tables were created to show sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR), the area under the curve (AUC), and so on. Results Based on the included 67 studies, the pooled sensitivity of urine LAM was 48% and specificity was 89%. In the subgroup analyses, the FujiLAM test had higher sensitivity (69%) and specificity (92%). Furthermore, among patients infected with human immunodeficiency virus (HIV), 50% of TB patients were diagnosed using a urine LAM test. Besides, the CD4+ cell count was inversely proportional to the sensitivity. Conclusions Urine LAM is a promising diagnostic test for TB, particularly using the FujiLAM in HIV‐infected adults whose CD4+ cell count is ≤100 per μl. Besides, the urine LAM test shows various sensitivities and specificities in different subgroups in terms of age, HIV infection status, CD4+ cell count, and testing method.
Collapse
Affiliation(s)
- Xin Yin
- Department of Clinical Laboratory Medicine, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Department of Pediatrics, The Pediatrics School of Guangzhou Medical University, Guangzhou, China
| | - Qi-Qing Ye
- Department of Pediatrics, The Pediatrics School of Guangzhou Medical University, Guangzhou, China
| | - Ke-Fan Wu
- Department of Clinical Medicine, The Sixth Clinical School of Guangzhou Medical university, Guangzhou, China
| | - Ji-Yuan Zeng
- Department of Pediatrics, The Pediatrics School of Guangzhou Medical University, Guangzhou, China
| | - Nan-Xi Li
- Department of Psychiatric Medicine, The Mental Health School of Guangzhou Medical University, Guangzhou, China
| | - Jun-Jian Mo
- Department of Clinical Medicine, The Sixth Clinical School of Guangzhou Medical university, Guangzhou, China
| | - Pei-Ying Huang
- Nanshan School, Guangzhou Medical University, Guangzhou, China
| | - Li-Min Xie
- Department of Clinical Medicine, The Third Clinical School of Guangzhou Medical University, Guangzhou, China
| | - Li-Ying Xie
- Department of Pediatrics, The Pediatrics School of Guangzhou Medical University, Guangzhou, China
| | - Xu-Guang Guo
- Department of Clinical Laboratory Medicine, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Department of Clinical Medicine, The Third Clinical School of Guangzhou Medical University, Guangzhou, China.,Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| |
Collapse
|
3
|
Field evaluation of a prototype tuberculosis lipoarabinomannan lateral flow assay on HIV-positive and HIV-negative patients. PLoS One 2021; 16:e0254156. [PMID: 34310609 PMCID: PMC8312950 DOI: 10.1371/journal.pone.0254156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 06/21/2021] [Indexed: 11/19/2022] Open
Abstract
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.
Collapse
|
4
|
Sossen B, Ryan A, Bielawski J, Greyling R, Matthews G, Hurribunce-James S, Goliath R, Caldwell J, Meintjes G. Urine lipoarabinomannan for rapid tuberculosis diagnosis in HIV-infected adult outpatients in Khayelitsha. South Afr J HIV Med 2021; 22:1226. [PMID: 34007476 PMCID: PMC8111664 DOI: 10.4102/sajhivmed.v22i1.1226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 03/22/2021] [Indexed: 11/09/2022] Open
Abstract
Background Decreasing tuberculosis (TB) mortality is constrained by diagnostic and treatment delays. The World Health Organization (WHO) recently actively recommended the point-of-care Alere Determine Lipoarabinomannan Ag assay (AlereLAM) to assist in the diagnosis of tuberculosis in specific HIV-infected outpatients. Objectives The primary objective of this study was to compare time to ambulatory TB treatment in HIV-infected adults with CD4 ≤ 100 cells/μL before and after (‘primary comparison groups’) availability of AlereLAM. In pre-specified subgroups, we prospectively assessed AlereLAM-positive prevalence. Method Clinicians prospectively performed AlereLAM in HIV-infected adults with TB symptoms and either CD4 ≤ 100 cells/μL or ‘seriously ill’ criteria. In a retrospective arm of equal duration, clinicians retrospectively collected data on HIV-infected adults with CD4 ≤ 100 cells/μL who initiated TB treatment. Results A total of 115 prospectively eligible adults (of whom 55 had CD4 ≤ 100 cells/μL) and 77 retrospectively eligible patients were included. In the primary comparison groups, the retrospective and prospective arms had similar age and sex distribution. With availability of AlereLAM, the time to TB treatment decreased from a median of 4 to 3 days (p = 0.0557). With availability of AlereLAM, same-day TB treatment initiation rose from 9.1% to 32.7% (p = 0.0006). In those with CD4 ≤ 100 only, those with ‘seriously ill’ criteria only, and in those meeting either, or both, of these criteria, AlereLAM was positive in 10.5%, 21.9%, 34.8% and 48.4% respectively. Conclusion Availability of AlereLAM led to more patients initiating same-day TB treatment. Using both CD4 ≤ 100 and ‘seriously ill’ criteria gave the greatest yield. Results of this study have informed local policy design.
Collapse
Affiliation(s)
- Bianca Sossen
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Amanda Ryan
- Town 2 Clinic, Cape Town City Health Department, Cape Town, South Africa
| | | | - Riana Greyling
- Matthew Goniwe Clinic, Cape Town City Health Department, Cape Town, South Africa
| | - Gillian Matthews
- Matthew Goniwe Clinic, Cape Town City Health Department, Cape Town, South Africa
| | | | - René Goliath
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Judy Caldwell
- Cape Town City Health Department, Cape Town, South Africa
| | - Graeme Meintjes
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
5
|
Zifodya JS, Kreniske JS, Schiller I, Kohli M, Dendukuri N, Schumacher SG, Ochodo EA, Haraka F, Zwerling AA, Pai M, Steingart KR, Horne DJ. Xpert Ultra versus Xpert MTB/RIF for pulmonary tuberculosis and rifampicin resistance in adults with presumptive pulmonary tuberculosis. Cochrane Database Syst Rev 2021; 2:CD009593. [PMID: 33616229 DOI: 10.1002/14651858.cd009593.pub5] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Xpert MTB/RIF and Xpert MTB/RIF Ultra (Xpert Ultra) are World Health Organization (WHO)-recommended rapid tests that simultaneously detect tuberculosis and rifampicin resistance in people with signs and symptoms of tuberculosis. This review builds on our recent extensive Cochrane Review of Xpert MTB/RIF accuracy. OBJECTIVES To compare the diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for the detection of pulmonary tuberculosis and detection of rifampicin resistance in adults with presumptive pulmonary tuberculosis. For pulmonary tuberculosis and rifampicin resistance, we also investigated potential sources of heterogeneity. We also summarized the frequency of Xpert Ultra trace-positive results, and estimated the accuracy of Xpert Ultra after repeat testing in those with trace-positive results. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, LILACS, Scopus, the WHO ICTRP, the ISRCTN registry, and ProQuest to 28 January 2020 with no language restriction. SELECTION CRITERIA We included diagnostic accuracy studies using respiratory specimens in adults with presumptive pulmonary tuberculosis that directly compared the index tests. For pulmonary tuberculosis detection, the reference standards were culture and a composite reference standard. For rifampicin resistance, the reference standards were culture-based drug susceptibility testing and line probe assays. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data using a standardized form, including data by smear and HIV status. We assessed risk of bias using QUADAS-2 and QUADAS-C. We performed meta-analyses comparing pooled sensitivities and specificities, separately for pulmonary tuberculosis detection and rifampicin resistance detection, and separately by reference standard. Most analyses used a bivariate random-effects model. For tuberculosis detection, we estimated accuracy in studies in participants who were not selected based on prior microscopy testing or history of tuberculosis. We performed subgroup analyses by smear status, HIV status, and history of tuberculosis. We summarized Xpert Ultra trace results. MAIN RESULTS We identified nine studies (3500 participants): seven had unselected participants (2834 participants). All compared Xpert Ultra and Xpert MTB/RIF for pulmonary tuberculosis detection; seven studies used a paired comparative accuracy design, and two studies used a randomized design. Five studies compared Xpert Ultra and Xpert MTB/RIF for rifampicin resistance detection; four studies used a paired design, and one study used a randomized design. Of the nine included studies, seven (78%) were mainly or exclusively in high tuberculosis burden countries. For pulmonary tuberculosis detection, most studies had low risk of bias in all domains. Pulmonary tuberculosis detection Xpert Ultra pooled sensitivity and specificity (95% credible interval) against culture were 90.9% (86.2 to 94.7) and 95.6% (93.0 to 97.4) (7 studies, 2834 participants; high-certainty evidence) versus Xpert MTB/RIF pooled sensitivity and specificity of 84.7% (78.6 to 89.9) and 98.4% (97.0 to 99.3) (7 studies, 2835 participants; high-certainty evidence). The difference in the accuracy of Xpert Ultra minus Xpert MTB/RIF was estimated at 6.3% (0.1 to 12.8) for sensitivity and -2.7% (-5.7 to -0.5) for specificity. If the point estimates for Xpert Ultra and Xpert MTB/RIF are applied to a hypothetical cohort of 1000 patients, where 10% of those presenting with symptoms have pulmonary tuberculosis, Xpert Ultra will miss 9 cases, and Xpert MTB/RIF will miss 15 cases. The number of people wrongly diagnosed with pulmonary tuberculosis would be 40 with Xpert Ultra and 14 with Xpert MTB/RIF. In smear-negative, culture-positive participants, pooled sensitivity was 77.5% (67.6 to 85.6) for Xpert Ultra versus 60.6% (48.4 to 71.7) for Xpert MTB/RIF; pooled specificity was 95.8% (92.9 to 97.7) for Xpert Ultra versus 98.8% (97.7 to 99.5) for Xpert MTB/RIF (6 studies). In people living with HIV, pooled sensitivity was 87.6% (75.4 to 94.1) for Xpert Ultra versus 74.9% (58.7 to 86.2) for Xpert MTB/RIF; pooled specificity was 92.8% (82.3 to 97.0) for Xpert Ultra versus 99.7% (98.6 to 100.0) for Xpert MTB/RIF (3 studies). In participants with a history of tuberculosis, pooled sensitivity was 84.2% (72.5 to 91.7) for Xpert Ultra versus 81.8% (68.7 to 90.0) for Xpert MTB/RIF; pooled specificity was 88.2% (70.5 to 96.6) for Xpert Ultra versus 97.4% (91.7 to 99.5) for Xpert MTB/RIF (4 studies). The proportion of Ultra trace-positive results ranged from 3.0% to 30.4%. Data were insufficient to estimate the accuracy of Xpert Ultra repeat testing in individuals with initial trace-positive results. Rifampicin resistance detection Pooled sensitivity and specificity were 94.9% (88.9 to 97.9) and 99.1% (97.7 to 99.8) (5 studies, 921 participants; high-certainty evidence) for Xpert Ultra versus 95.3% (90.0 to 98.1) and 98.8% (97.2 to 99.6) (5 studies, 930 participants; high-certainty evidence) for Xpert MTB/RIF. The difference in the accuracy of Xpert Ultra minus Xpert MTB/RIF was estimated at -0.3% (-6.9 to 5.7) for sensitivity and 0.3% (-1.2 to 2.0) for specificity. If the point estimates for Xpert Ultra and Xpert MTB/RIF are applied to a hypothetical cohort of 1000 patients, where 10% of those presenting with symptoms have rifampicin resistance, Xpert Ultra will miss 5 cases, and Xpert MTB/RIF will miss 5 cases. The number of people wrongly diagnosed with rifampicin resistance would be 8 with Xpert Ultra and 11 with Xpert MTB/RIF. We identified a higher number of rifampicin resistance indeterminate results with Xpert Ultra, pooled proportion 7.6% (2.4 to 21.0) compared to Xpert MTB/RIF pooled proportion 0.8% (0.2 to 2.4). The estimated difference in the pooled proportion of indeterminate rifampicin resistance results for Xpert Ultra versus Xpert MTB/RIF was 6.7% (1.4 to 20.1). AUTHORS' CONCLUSIONS Xpert Ultra has higher sensitivity and lower specificity than Xpert MTB/RIF for pulmonary tuberculosis, especially in smear-negative participants and people living with HIV. Xpert Ultra specificity was lower than that of Xpert MTB/RIF in participants with a history of tuberculosis. The sensitivity and specificity trade-off would be expected to vary by setting. For detection of rifampicin resistance, Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity. Ultra trace-positive results were common. Xpert Ultra and Xpert MTB/RIF provide accurate results and can allow rapid initiation of treatment for rifampicin-resistant and multidrug-resistant tuberculosis.
Collapse
Affiliation(s)
- Jerry S Zifodya
- Department of Medicine, Section of Pulmonary, Critical Care, & Environmental Medicine , Tulane University, New Orleans, LA, USA
| | - Jonah S Kreniske
- Department of Internal Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Ian Schiller
- Centre for Outcomes Research, McGill University Health Centre - Research Institute, Montreal, Canada
| | - Mikashmi Kohli
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
| | - Nandini Dendukuri
- Centre for Outcomes Research, McGill University Health Centre - Research Institute, Montreal, Canada
| | | | - Eleanor A Ochodo
- Centre for Evidence-based Health Care, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Frederick Haraka
- Elizabeth Glaser Pediatric AIDS Foundation, Dar es Salaam, Tanzania
- Ifakara Health Institute, Bagamoyo, Tanzania
| | - Alice A Zwerling
- School of Epidemiology & Public Health, University of Ottawa, Ottawa, Canada
| | - Madhukar Pai
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
| | - Karen R Steingart
- Honorary Research Fellow, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David J Horne
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, and Firland Northwest TB Center, University of Washington, Seattle, WA, USA
| |
Collapse
|
6
|
Chatla C, Mishra N, Jojula M, Adepu R, Puttala M. A systematic review of utility of urine lipoarabinomannan in detecting tuberculosis among HIV-positive tuberculosis suspects. Lung India 2021; 38:64-73. [PMID: 33402640 PMCID: PMC8066934 DOI: 10.4103/lungindia.lungindia_574_19] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Sputum smear microscopy (SSM), though regarded as an inexpensive and popular method for detecting tuberculosis (TB), lacks adequate sensitivity, specifically in adult people living with HIV/AIDS (PLHIV). Urine lipoarabinomannan (LAM) is a promising diagnostic tool among PLHIV with CD4 cell count < 200 cells/μl. We attempted to review all the studies undertaken in identifying the utility of urine LAM in diagnosing TB, especially among PLHIV. We searched PubMed, Google Scholar, and MEDLINE databases for studies reporting diagnostic utility of urine LAM status in PLHIV, published in the last 20 years till December 2019. The keywords used for searching were “Tuberculosis,” “HIV/AIDS,” “Diagnosis,” “Screening” “Lipoarabinomannan,” and “Urine.” Our search resulted in 137 shortlisted citations, of which 67 related manuscripts were identified for detailed study. Based on inclusion and exclusion criteria, 37 studies were reviewed in detail. Average sample size of these studies was 464 (range = 81–2528; SD = 427). Crude average sensitivity of urine LAM in culture-confirmed TB cases was 44.1% (range = 8.3–93) while that of SSM was 38.6% (range = 14–65). However, sensitivity of urine LAM + SSM was 60.4% (range = 38.3–92.7), demonstrating the utility of SSM + urine LAM combination for detecting TB. Specificity was similar between urine LAM and SSM with 92.7% (range = 76–100) and 97.9% (range = 93.9–100), respectively. Majority of the studies demonstrated higher sensitivity of urine LAM in those with lesser the CD4 count, with immunocompromised and with debilitation who cannot produce self-expectorated sputum. We conclude that urine LAM is a potential diagnostic test in the algorithms involving immunocompromised, debilitated patients and specifically in PLHIV whose CD4 count is ≤100 cells/μl.
Collapse
Affiliation(s)
- Chakrapani Chatla
- Symbiosis School of Biological Sciences, Symbiosis International (Deemed University), Pune, Maharashtra; Department of Microbiology, Sri Shivani College of Pharmacy, Warangal, Telangana, India
| | - Neetu Mishra
- Symbiosis School of Biological Sciences, Symbiosis International (Deemed University), Pune, Maharashtra, India
| | - Malathi Jojula
- Department of Microbiology, Sri Shivani College of Pharmacy, Warangal, Telangana, India
| | | | | |
Collapse
|
7
|
Gupta A, Kumar A, Ashraf AA, Madigubba H, Chawla K. A pilot study to evaluate urine LAM assay for diagnosis of pulmonary tuberculosis among non-HIV patients. Trop Doct 2020; 50:343-346. [PMID: 32638652 DOI: 10.1177/0049475520936164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There is a great need to improve diagnostic tools for tuberculosis where the majority are without HIV co-infection in resource-poor settings and high-burden areas such as India. The urine LAM assay has not hitherto been studied and may have a role to play. Our study found that, as a stand-alone diagnostic tool, the assay was suboptimal when compared to Xpert MTB/Rif. However, a combination of LAM assay along with sputum microscopy may be useful in settings where molecular testing is unavailable.
Collapse
Affiliation(s)
- Akshita Gupta
- Junior Resident, Department of Microbiology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Ajay Kumar
- Research Fellow, Department of Microbiology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Asem Ali Ashraf
- Junior Resident, Department of Microbiology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Haritha Madigubba
- Junior Resident, Department of Microbiology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Kiran Chawla
- Professor, Department of Microbiology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| |
Collapse
|
8
|
Should Urine-LAM Tests Be Used in TB Symptomatic HIV-Positive Patients When No CD4 Count Is Available? A Prospective Observational Cohort Study From Malawi. J Acquir Immune Defic Syndr 2020; 83:24-30. [PMID: 31633613 PMCID: PMC6903332 DOI: 10.1097/qai.0000000000002206] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Supplemental Digital Content is Available in the Text. Current eligibility criteria for urine lateral-flow lipoarabinomannan assay (LF-LAM) in ambulatory, HIV-positive patients rely on the CD4 count. We investigated the diagnostic yield of LF-LAM and the 6-month mortality in ambulatory, TB symptomatic, HIV-positive patients regardless of their CD4 count.
Collapse
|
9
|
Yoon C, Semitala FC, Asege L, Katende J, Mwebe S, Andama AO, Atuhumuza E, Nakaye M, Armstrong DT, Dowdy DW, McCulloch CE, Kamya M, Cattamanchi A. Yield and Efficiency of Novel Intensified Tuberculosis Case-Finding Algorithms for People Living with HIV. Am J Respir Crit Care Med 2020; 199:643-650. [PMID: 30192649 DOI: 10.1164/rccm.201803-0490oc] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
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.
Collapse
Affiliation(s)
- Christina Yoon
- 1 Division of Pulmonary & Critical Care Medicine, Department of Medicine, Zuckerberg San Francisco General Hospital, and
| | - Fred C Semitala
- 2 Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda.,3 Makerere University Joint AIDS Program, Kampala, Uganda
| | - Lucy Asege
- 4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | - Jane Katende
- 3 Makerere University Joint AIDS Program, Kampala, Uganda
| | - Sandra Mwebe
- 4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | - Alfred O Andama
- 2 Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda.,4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | - Elly Atuhumuza
- 4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | - Martha Nakaye
- 4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | | | - David W Dowdy
- 6 Division of Infectious Disease Epidemiology, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and
| | - Charles E McCulloch
- 7 Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California
| | - Moses Kamya
- 2 Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda.,3 Makerere University Joint AIDS Program, Kampala, Uganda.,4 Makerere University-University of California, San Francisco Research Collaboration, Kampala, Uganda
| | - Adithya Cattamanchi
- 1 Division of Pulmonary & Critical Care Medicine, Department of Medicine, Zuckerberg San Francisco General Hospital, and.,8 Curry International Tuberculosis Center, University of California, San Francisco, Oakland, California
| |
Collapse
|
10
|
Brief Report: Real-World Performance and Interobserver Agreement of Urine Lipoarabinomannan in Diagnosing HIV-Associated Tuberculosis in an Emergency Center. J Acquir Immune Defic Syndr 2019; 81:e10-e14. [PMID: 30865176 DOI: 10.1097/qai.0000000000002002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The urine lipoarabinomannan (LAM) lateral flow assay is a point-of-care test to diagnose HIV-associated tuberculosis (TB). We assessed the performance of urine LAM in HIV-positive patients presenting to the emergency center and evaluated the interobserver agreement between emergency center physicians and laboratory technologists. SETTING A cross-sectional diagnostic study was performed at the emergency center of a district hospital in a high HIV-prevalence community in South Africa. METHODS Consecutive HIV-positive adults presenting with ≥1 WHO TB symptom were enrolled over a 16-month period. A urine LAM test was performed at point-of-care by an emergency physician and interpreted independently by 2 physicians. A second test was performed in the laboratory and interpreted independently by 2 laboratory technologists. The reference standard was a positive TB culture or Xpert MTB/RIF test on sputum or appropriate extrapulmonary samples. We compared diagnostic accuracy and reproducibility of urine LAM between point-of-care readers and laboratory readers. RESULTS One thousand three hundred eighty-eight samples (median, 3 samples/participant) were sent for TB microbiology tests in 411 participants; 170 had confirmed TB (41.4%). Point-of-care and laboratory-performed urine LAM had similar sensitivity (41.8% vs 42.0%, P = 1.0) and specificity (90.5% vs 87.5%, P = 0.23). Moderate agreement was found between point-of-care and laboratory testing (κ = 0.62), but there was strong agreement between point-of-care readers (κ = 0.95) and between laboratory readers (κ = 0.94). Positive percent agreement between point-of-care and laboratory readers was 68% and negative percent agreement 92%. CONCLUSION There is no diagnostic accuracy advantage in laboratory-performed versus point-of-care-performed urine LAM tests in emergency care centers in high-burden settings.
Collapse
|
11
|
Bjerrum S, Schiller I, Dendukuri N, Kohli M, Nathavitharana RR, Zwerling AA, Denkinger CM, Steingart KR, Shah M. Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in people living with HIV. Cochrane Database Syst Rev 2019; 10:CD011420. [PMID: 31633805 PMCID: PMC6802713 DOI: 10.1002/14651858.cd011420.pub3] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The lateral flow urine lipoarabinomannan (LF-LAM) assay Alere Determine™ TB LAM Ag is recommended by the World Health Organization (WHO) to help detect active tuberculosis in HIV-positive people with severe HIV disease. This review update asks the question, "does new evidence justify the use of LF-LAM in a broader group of people?", and is part of the WHO process for updating guidance on the use of LF-LAM. OBJECTIVES To assess the accuracy of LF-LAM for the diagnosis of active tuberculosis among HIV-positive adults with signs and symptoms of tuberculosis (symptomatic participants) and among HIV-positive adults irrespective of signs and symptoms of tuberculosis (unselected participants not assessed for tuberculosis signs and symptoms).The proposed role for LF-LAM is as an add on to clinical judgement and with other tests to assist in diagnosing tuberculosis. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register; MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, without language restriction to 11 May 2018. SELECTION CRITERIA Randomized trials, cross-sectional, and observational cohort studies that evaluated LF-LAM for active tuberculosis (pulmonary and extrapulmonary) in HIV-positive adults. We included studies that used the manufacturer's recommended threshold for test positivity, either the updated reference card with four bands (grade 1 of 4) or the corresponding prior reference card grade with five bands (grade 2 of 5). The reference standard was culture or nucleic acid amplification test from any body site (microbiological). We considered a higher quality reference standard to be one in which two or more specimen types were evaluated for tuberculosis diagnosis and a lower quality reference standard to be one in which only one specimen type was evaluated. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data using a standardized form and REDCap electronic data capture tools. We appraised the quality of studies using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool and performed meta-analyses to estimate pooled sensitivity and specificity using a bivariate random-effects model and a Bayesian approach. We analyzed studies enrolling strictly symptomatic participants separately from those enrolling unselected participants. We investigated pre-defined sources of heterogeneity including the influence of CD4 count and clinical setting on the accuracy estimates. We assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS We included 15 unique studies (nine new studies and six studies from the original review that met the inclusion criteria): eight studies among symptomatic adults and seven studies among unselected adults. All studies were conducted in low- or middle-income countries. Risk of bias was high in the patient selection and reference standard domains, mainly because studies excluded participants unable to produce sputum and used a lower quality reference standard.Participants with tuberculosis symptomsLF-LAM pooled sensitivity (95% credible interval (CrI) ) was 42% (31% to 55%) (moderate-certainty evidence) and pooled specificity was 91% (85% to 95%) (very low-certainty evidence), (8 studies, 3449 participants, 37% with tuberculosis).For a population of 1000 people where 300 have microbiologically-confirmed tuberculosis, the utilization of LF-LAM would result in: 189 to be LF-LAM positive: of these, 63 (33%) would not have tuberculosis (false-positives); and 811 to be LF-LAM negative: of these, 174 (21%) would have tuberculosis (false-negatives).By clinical setting, pooled sensitivity was 52% (40% to 64%) among inpatients versus 29% (17% to 47%) among outpatients; and pooled specificity was 87% (78% to 93%) among inpatients versus 96% (91% to 99%) among outpatients. Stratified by CD4 cell count, pooled sensitivity increased, and specificity decreased with lower CD4 cell count.Unselected participants not assessed for signs and symptoms of tuberculosisLF-LAM pooled sensitivity was 35% (22% to 50%), (moderate-certainty evidence) and pooled specificity was 95% (89% to 96%), (low-certainty evidence), (7 studies, 3365 participants, 13% with tuberculosis).For a population of 1000 people where 100 have microbiologically-confirmed tuberculosis, the utilization of LF-LAM would result in: 80 to be LF-LAM positive: of these, 45 (56%) would not have tuberculosis (false-positives); and 920 to be LF-LAM negative: of these, 65 (7%) would have tuberculosis (false-negatives).By clinical setting, pooled sensitivity was 62% (41% to 83%) among inpatients versus 31% (18% to 47%) among outpatients; pooled specificity was 84% (48% to 96%) among inpatients versus 95% (87% to 99%) among outpatients. Stratified by CD4 cell count, pooled sensitivity increased, and specificity decreased with lower CD4 cell count. AUTHORS' CONCLUSIONS We found that LF-LAM has a sensitivity of 42% to diagnose tuberculosis in HIV-positive individuals with tuberculosis symptoms and 35% in HIV-positive individuals not assessed for tuberculosis symptoms, consistent with findings reported previously. Regardless of how people are enrolled, sensitivity is higher in inpatients and those with lower CD4 cell, but a concomitant lower specificity. As a simple point-of-care test that does not depend upon sputum evaluation, LF-LAM may assist with the diagnosis of tuberculosis, particularly when a sputum specimen cannot be produced.
Collapse
Affiliation(s)
- Stephanie Bjerrum
- University of Southern DenmarkDepartment of Clinical Research, Research Unit of Infectious DiseasesOdenseDenmark
- Odense University HospitalMyCRESD, Mycobacterial Research Centre of Southern Denmark, Department of Infectious DiseasesSdr. Boulevard 29OdenseDenmark
- Odense University HospitalOPEN, Odense Patient data Explorative NetworkOdenseDenmarkDenmark
| | - Ian Schiller
- McGill University Health Centre ‐ Research InstituteDivision of Clinical EpidemiologyMontrealQCCanada
| | - Nandini Dendukuri
- McGill University Health Centre ‐ Research InstituteDivision of Clinical EpidemiologyMontrealQCCanada
| | - Mikashmi Kohli
- McGill UniversityDepartment of Epidemiology, Biostatistics and Occupational HealthMontrealCanada
| | - Ruvandhi R Nathavitharana
- Beth Israel Deaconess Medical Center, Harvard Medical SchoolDivision of Infectious DiseasesBostonUSA
| | - Alice A Zwerling
- University of OttawaSchool of Epidemiology & Public Health600 Peter Morand Crescent, Room 301EOttawaOntarioCanadaK1G5Z3
| | - Claudia M Denkinger
- FINDGenevaSwitzerland
- University Hospital HeidelbergCenter of Infectious DiseasesHeidelbergGermany
| | - Karen R Steingart
- Department of Clinical Sciences, Liverpool School of Tropical MedicineHonorary Research FellowPembroke PlaceLiverpoolUK
| | - Maunank Shah
- John Hopkins University School of MedicineDepartment of Medicine, Division of Infectious DiseasesBaltimoreMarylandUSA
| | | |
Collapse
|
12
|
Andama A, Jaganath D, Crowder R, Asege L, Nakaye M, Katumba D, Mwebe S, Semitala F, Worodria W, Joloba M, Mohanty S, Somoskovi A, Cattamanchi A. Accuracy and incremental yield of urine Xpert MTB/RIF Ultra versus Determine TB-LAM for diagnosis of pulmonary tuberculosis. Diagn Microbiol Infect Dis 2019; 96:114892. [PMID: 31727376 DOI: 10.1016/j.diagmicrobio.2019.114892] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/09/2019] [Accepted: 08/29/2019] [Indexed: 02/07/2023]
Abstract
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.
Collapse
Affiliation(s)
- A Andama
- Department of Internal Medicine, Makerere University College of Health Sciences, Kampala, Uganda; Infectious Diseases Research Collaboration, Kampala, Uganda.
| | - D Jaganath
- University of California, San Francisco, Department of Medicine, Division of Pulmonary & Critical Care Medicine, San Francisco, California, USA; University of California, San Francisco, Department of Pediatrics, Division of Pediatric Infectious Diseases, San Francisco, California, USA; Center for Tuberculosis, University of California, San Francisco, San Francisco, California, USA
| | - R Crowder
- University of California, San Francisco, Department of Medicine, Division of Pulmonary & Critical Care Medicine, San Francisco, California, USA; Center for Tuberculosis, University of California, San Francisco, San Francisco, California, USA
| | - L Asege
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - M Nakaye
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - D Katumba
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - S Mwebe
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - F Semitala
- Department of Internal Medicine, Makerere University College of Health Sciences, Kampala, Uganda; Infectious Diseases Research Collaboration, Kampala, Uganda
| | - W Worodria
- Department of Internal Medicine, Makerere University College of Health Sciences, Kampala, Uganda; Mulago National Referral Hospital, Kampala, Uganda
| | - M Joloba
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
| | - S Mohanty
- University of Utah, Department of Metallurgical Engineering, Department of Chemical Engineering, Salt Lake City, USA
| | - A Somoskovi
- Global Good Intellectual Ventures Laboratory, Seattle, USA
| | - A Cattamanchi
- University of California, San Francisco, Department of Medicine, Division of Pulmonary & Critical Care Medicine, San Francisco, California, USA; Center for Tuberculosis, University of California, San Francisco, San Francisco, California, USA; Center for Vulnerable Populations, Department of Medicine, University of California, San Francisco, USA; Curry International Tuberculosis Center, University of California, San Francisco, USA
| |
Collapse
|
13
|
Horne DJ, Kohli M, Zifodya JS, Schiller I, Dendukuri N, Tollefson D, Schumacher SG, Ochodo EA, Pai M, Steingart KR. Xpert MTB/RIF and Xpert MTB/RIF Ultra for pulmonary tuberculosis and rifampicin resistance in adults. Cochrane Database Syst Rev 2019; 6:CD009593. [PMID: 31173647 PMCID: PMC6555588 DOI: 10.1002/14651858.cd009593.pub4] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Xpert MTB/RIF (Xpert MTB/RIF) and Xpert MTB/RIF Ultra (Xpert Ultra), the newest version, are the only World Health Organization (WHO)-recommended rapid tests that simultaneously detect tuberculosis and rifampicin resistance in persons with signs and symptoms of tuberculosis, at lower health system levels. A previous Cochrane Review found Xpert MTB/RIF sensitive and specific for tuberculosis (Steingart 2014). Since the previous review, new studies have been published. We performed a review update for an upcoming WHO policy review. OBJECTIVES To determine diagnostic accuracy of Xpert MTB/RIF and Xpert Ultra for tuberculosis in adults with presumptive pulmonary tuberculosis (PTB) and for rifampicin resistance in adults with presumptive rifampicin-resistant tuberculosis. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, to 11 October 2018, without language restriction. SELECTION CRITERIA Randomized trials, cross-sectional, and cohort studies using respiratory specimens that evaluated Xpert MTB/RIF, Xpert Ultra, or both against the reference standard, culture for tuberculosis and culture-based drug susceptibility testing or MTBDRplus for rifampicin resistance. DATA COLLECTION AND ANALYSIS Four review authors independently extracted data using a standardized form. When possible, we also extracted data by smear and HIV status. We assessed study quality using QUADAS-2 and performed meta-analyses to estimate pooled sensitivity and specificity separately for tuberculosis and rifampicin resistance. We investigated potential sources of heterogeneity. Most analyses used a bivariate random-effects model. For tuberculosis detection, we first estimated accuracy using all included studies and then only the subset of studies where participants were unselected, i.e. not selected based on prior microscopy testing. MAIN RESULTS We identified in total 95 studies (77 new studies since the previous review): 86 studies (42,091 participants) evaluated Xpert MTB/RIF for tuberculosis and 57 studies (8287 participants) for rifampicin resistance. One study compared Xpert MTB/RIF and Xpert Ultra on the same participant specimen.Tuberculosis detectionOf the total 86 studies, 45 took place in high tuberculosis burden and 50 in high TB/HIV burden countries. Most studies had low risk of bias.Xpert MTB/RIF pooled sensitivity and specificity (95% credible Interval (CrI)) were 85% (82% to 88%) and 98% (97% to 98%), (70 studies, 37,237 unselected participants; high-certainty evidence). We found similar accuracy when we included all studies.For a population of 1000 people where 100 have tuberculosis on culture, 103 would be Xpert MTB/RIF-positive and 18 (17%) would not have tuberculosis (false-positives); 897 would be Xpert MTB/RIF-negative and 15 (2%) would have tuberculosis (false-negatives).Xpert Ultra sensitivity (95% confidence interval (CI)) was 88% (85% to 91%) versus Xpert MTB/RIF 83% (79% to 86%); Xpert Ultra specificity was 96% (94% to 97%) versus Xpert MTB/RIF 98% (97% to 99%), (1 study, 1439 participants; moderate-certainty evidence).Xpert MTB/RIF pooled sensitivity was 98% (97% to 98%) in smear-positive and 67% (62% to 72%) in smear-negative, culture-positive participants, (45 studies). Xpert MTB/RIF pooled sensitivity was 88% (83% to 92%) in HIV-negative and 81% (75% to 86%) in HIV-positive participants; specificities were similar 98% (97% to 99%), (14 studies).Rifampicin resistance detectionXpert MTB/RIF pooled sensitivity and specificity (95% Crl) were 96% (94% to 97%) and 98% (98% to 99%), (48 studies, 8020 participants; high-certainty evidence).For a population of 1000 people where 100 have rifampicin-resistant tuberculosis, 114 would be positive for rifampicin-resistant tuberculosis and 18 (16%) would not have rifampicin resistance (false-positives); 886 would be would be negative for rifampicin-resistant tuberculosis and four (0.4%) would have rifampicin resistance (false-negatives).Xpert Ultra sensitivity (95% CI) was 95% (90% to 98%) versus Xpert MTB/RIF 95% (91% to 98%); Xpert Ultra specificity was 98% (97% to 99%) versus Xpert MTB/RIF 98% (96% to 99%), (1 study, 551 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS We found Xpert MTB/RIF to be sensitive and specific for diagnosing PTB and rifampicin resistance, consistent with findings reported previously. Xpert MTB/RIF was more sensitive for tuberculosis in smear-positive than smear-negative participants and HIV-negative than HIV-positive participants. Compared with Xpert MTB/RIF, Xpert Ultra had higher sensitivity and lower specificity for tuberculosis and similar sensitivity and specificity for rifampicin resistance (1 study). Xpert MTB/RIF and Xpert Ultra provide accurate results and can allow rapid initiation of treatment for multidrug-resistant tuberculosis.
Collapse
Affiliation(s)
- David J Horne
- University of WashingtonDepartment of Medicine, Division of Pulmonary and Critical Care Medicine, and Firland Northwest TB CenterSeattleUSA
| | - Mikashmi Kohli
- McGill UniversityDepartment of Epidemiology, Biostatistics and Occupational HealthMontrealCanada
| | - Jerry S Zifodya
- University of WashingtonPulmonary and Critical Care Medicine325 9th Avenue – Campus Box 359762SeattleUSA98104
| | - Ian Schiller
- McGill University Health Centre ‐ Research InstituteDivision of Clinical EpidemiologyMontrealCanada
| | - Nandini Dendukuri
- McGill University Health Centre ‐ Research InstituteDivision of Clinical EpidemiologyMontrealCanada
| | | | | | - Eleanor A Ochodo
- Stellenbosch UniversityCentre for Evidence‐based Health Care, Faculty of Medicine and Health SciencesPO Box 241Cape TownSouth Africa8000
| | - Madhukar Pai
- McGill UniversityDepartment of Epidemiology, Biostatistics and Occupational HealthMontrealCanada
| | - Karen R Steingart
- Department of Clinical Sciences, Liverpool School of Tropical MedicineHonorary Research FellowPembroke PlaceLiverpoolUK
| |
Collapse
|
14
|
Huerga H, Mathabire Rucker SC, Cossa L, Bastard M, Amoros I, Manhiça I, Mbendera K, Telnov A, Szumilin E, Sanchez-Padilla E, Molfino L. Diagnostic value of the urine lipoarabinomannan assay in HIV-positive, ambulatory patients with CD4 below 200 cells/μl in 2 low-resource settings: A prospective observational study. PLoS Med 2019; 16:e1002792. [PMID: 31039161 PMCID: PMC6490904 DOI: 10.1371/journal.pmed.1002792] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/28/2019] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Current guidelines recommend the use of the lateral flow urine lipoarabinomannan assay (LAM) in HIV-positive, ambulatory patients with signs and symptoms of tuberculosis (TB) only if they are seriously ill or have CD4 count ≤ 100 cells/μl. We assessed the diagnostic yield of including LAM in TB diagnostic algorithms in HIV-positive, ambulatory patients with CD4 < 200 cells/μl, as well as the risk of mortality in LAM-positive patients who were not diagnosed using other diagnostic tools and not treated for TB. METHODS AND FINDINGS We conducted a prospective observational study including HIV-positive adult patients with signs and symptoms of TB and CD4 < 200 cells/μl attending 6 health facilities in Malawi and Mozambique. Patients were included consecutively from 18 September 2015 to 27 October 2016 in Malawi and from 3 December 2014 to 22 August 2016 in Mozambique. All patients had a clinical exam and LAM, chest X-ray, sputum microscopy, and Xpert MTB/RIF assay (Xpert) requested. Culture in sputum was done for a subset of patients. The diagnostic yield was defined as the proportion of patients with a positive assay result among those with laboratory-confirmed TB. For the 456 patients included in the study, the median age was 36 years (IQR 31-43) and the median CD4 count was 50 cells/μl (IQR 21-108). Forty-five percent (205/456) of the patients had laboratory-confirmed TB. The diagnostic yields of LAM, microscopy, and Xpert were 82.4% (169/205), 33.7% (69/205), and 40.0% (84/205), respectively. In total, 50.2% (103/205) of the patients with laboratory-confirmed TB were diagnosed only through LAM. Overall, the use of LAM in diagnostic algorithms increased the yield of algorithms with microscopy and with Xpert by 38.0% (78/205) and 34.6% (71/205), respectively, and, specifically among patients with CD4 100-199 cells/μl, by 27.5% (14/51) and 29.4% (15/51), respectively. LAM-positive patients not diagnosed through other tools and not treated for TB had a significantly higher risk of mortality than LAM-positive patients who received treatment (adjusted risk ratio 2.57, 95% CI 1.27-5.19, p = 0.009). Although the TB diagnostic conditions in the study sites were similar to those in other resource-limited settings, the added value of LAM may depend on the availability of microscopy or Xpert results. CONCLUSIONS LAM has diagnostic value for identifying TB in HIV-positive patients with signs and symptoms of TB and advanced immunodeficiency, including those with a CD4 count of 100-199 cells/μl. In this study, the use of LAM enabled the diagnosis of TB in half of the patients with confirmed TB disease; without LAM, these patients would have been missed. The rapid identification and treatment of TB enabled by LAM may decrease overall mortality risk for these patients.
Collapse
Affiliation(s)
| | | | - Loide Cossa
- Médecins Sans Frontières, Maputo, Mozambique
| | | | | | | | | | - Alex Telnov
- Médecins Sans Frontières, Geneva, Switzerland
| | | | | | | |
Collapse
|
15
|
Boyles TH, Griesel R, Stewart A, Mendelson M, Maartens G. Incremental yield and cost of urine Determine TB-LAM and sputum induction in seriously ill adults with HIV. Int J Infect Dis 2018; 75:67-73. [PMID: 30125689 PMCID: PMC6202059 DOI: 10.1016/j.ijid.2018.08.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/07/2018] [Accepted: 08/09/2018] [Indexed: 11/23/2022] Open
Abstract
Background: Tuberculosis is a major cause of mortality among HIV-infected inpatients, and the World Health Organization (WHO) recommends an algorithm to improve diagnosis. The urine lateral flow lipoarabinomannan (LAM) and sputum Xpert MTB/RIF tests are promising tools, but the optimal diagnostic algorithm is unclear. Methods: This prospective cohort study enrolled HIV-positive inpatients with cough and WHO danger signs. The Xpert MTB/RIF test and mycobacterial culture were performed on sputum using sputum induction when necessary, and the LAM test was performed on stored urine. Tuberculosis was diagnosed by culture from any site. The diagnostic accuracy and costs of testing were determined for single and combined tests. Results: Tuberculosis was confirmed in 169 of 332 patients (50.9%). The yield of LAM, Xpert MTB/RIF on spontaneous sputum (Xpert Spot), and Xpert MTB/RIF on spontaneous or induced sputum (Xpert SI) was 35.5%, 23.1%, and 90.5%, respectively. When LAM was placed before Xpert Spot and Xpert SI in an algorithm, the yield was 50.9% and 92.3%, respectively. Adding culture to Xpert MTB/RIF only increased the yield by 1.2% and 2.7%, respectively. Use of the LAM test reduced costs. Conclusions: Sputum induction is important to increase the yield of Xpert MTB/RIF for seriously ill patients with HIV and cough. LAM testing has little effect on yield when sputum induction is available, but reduces costs and may have other benefits.
Collapse
Affiliation(s)
- Tom H Boyles
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town, Cape Town, South Africa.
| | - Rulan Griesel
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Annemie Stewart
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Marc Mendelson
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Gary Maartens
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
16
|
Gounden S, Perumal R, Magula NP. Extrapulmonary tuberculosis in the setting of HIV hyperendemicity at a tertiary hospital in Durban, South Africa. S Afr J Infect Dis 2018. [DOI: 10.1080/23120053.2017.1403207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
- S Gounden
- Department of Internal Medicine, School of Clinical Medicine, University of KwaZulu-Natal , Durban, South Africa
| | - R Perumal
- Department of Pulmonology and Critical Care, Centre for the AIDS Programme of Research in South Africa, University of KwaZulu-Natal , Durban, South Africa
| | - NP Magula
- Department of Internal Medicine, School of Clinical Medicine, University of KwaZulu-Natal , Durban, South Africa
| |
Collapse
|
17
|
Point of care diagnostics for tuberculosis. Pulmonology 2018; 24:73-85. [DOI: 10.1016/j.rppnen.2017.12.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 12/07/2017] [Indexed: 01/01/2023] Open
|
18
|
Drain PK, Losina E, Coleman SM, Giddy J, Ross D, Katz JN, Freedberg KA, Bassett IV. Clinic-Based Urinary Lipoarabinomannan as a Biomarker of Clinical Disease Severity and Mortality Among Antiretroviral Therapy-Naive Human Immunodeficiency Virus-Infected Adults in South Africa. Open Forum Infect Dis 2017; 4:ofx167. [PMID: 28979922 PMCID: PMC5622366 DOI: 10.1093/ofid/ofx167] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 08/08/2017] [Indexed: 01/29/2023] Open
Abstract
Background Urinary lipoarabinomannan (LAM) has limited sensitivity for diagnosing active human immunodeficiency virus (HIV)-associated tuberculosis (TB) disease, but LAM screening at HIV diagnosis might identify adults with more severe clinical disease or greater risk of mortality. Methods We enrolled antiretroviral therapy-naive HIV-infected adults from 4 clinics in Durban. Nurses performed urine LAM testing using a rapid assay (Determine TB LAM) graded from low (1+) to high (≥3+) intensity. Urine LAM results were not used to guide anti-TB therapy. We assessed TB-related symptoms and obtained sputum for mycobacterial smear and culture. Participants were observed for 12 months, and we used multivariable Cox proportional hazard models to determine hazard ratios for all-cause mortality. Results Among 726 HIV-infected adults with median CD4 of 205 cells/mm3 (interquartile range, 79–350 cells/mm3), 93 (13%) were LAM positive and 89 (12%) participants died during the follow-up period. In multivariable analyses, urine LAM-positive participants had a mortality hazard ratio (MHR) of 3.58 (95% confidence interval [CI], 2.20–5.81) for all-cause mortality. Among participants with mycobacterial-confirmed TB, urine LAM-positivity had a 2.91 (95% CI, 1.26–6.73) MHR for all participants and a 4.55 (95% CI, 1.71–12.1) MHR for participants with CD4 ≤100 cell/mm3. Participants with LAM-positive TB had significantly more clinical signs and symptoms of disease, compared with participants with LAM-negative TB disease. Conclusions Among HIV-infected adults, urinary LAM-positive patients had more clinical disease severity and a 3-fold increase in 12-month mortality compared with those who were LAM negative.
Collapse
Affiliation(s)
- Paul K Drain
- Departments of Global Health.,Medicine, and.,Epidemiology, University of Washington, Seattle; Departments of.,Surgery and
| | - Elena Losina
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachussetts.,Boston University School of Public Health, Massachussetts
| | | | - Janet Giddy
- Department of Medicine, McCord Hospital, Durban, South Africa
| | - Douglas Ross
- Department of Medicine, St. Mary's Hospital, Durban, South Africa
| | - Jeffrey N Katz
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachussetts
| | - Kenneth A Freedberg
- Medicine, Massachusetts General Hospital, Harvard Medical School, Boston.,Boston University School of Public Health, Massachussetts
| | - Ingrid V Bassett
- Medicine, Massachusetts General Hospital, Harvard Medical School, Boston
| |
Collapse
|
19
|
Incremental Yield of Including Determine-TB LAM Assay in Diagnostic Algorithms for Hospitalized and Ambulatory HIV-Positive Patients in Kenya. PLoS One 2017; 12:e0170976. [PMID: 28125693 PMCID: PMC5268475 DOI: 10.1371/journal.pone.0170976] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 01/13/2017] [Indexed: 11/19/2022] Open
Abstract
Background Determine-TB LAM assay is a urine point-of-care test useful for TB diagnosis in HIV-positive patients. We assessed the incremental diagnostic yield of adding LAM to algorithms based on clinical signs, sputum smear-microscopy, chest X-ray and Xpert MTB/RIF in HIV-positive patients with symptoms of pulmonary TB (PTB). Methods Prospective observational cohort of ambulatory (either severely ill or CD4<200cells/μl or with Body Mass Index<17Kg/m2) and hospitalized symptomatic HIV-positive adults in Kenya. Incremental diagnostic yield of adding LAM was the difference in the proportion of confirmed TB patients (positive Xpert or MTB culture) diagnosed by the algorithm with LAM compared to the algorithm without LAM. The multivariable mortality model was adjusted for age, sex, clinical severity, BMI, CD4, ART initiation, LAM result and TB confirmation. Results Among 474 patients included, 44.1% were severely ill, 69.6% had CD4<200cells/μl, 59.9% had initiated ART, 23.2% could not produce sputum. LAM, smear-microscopy, Xpert and culture in sputum were positive in 39.0% (185/474), 21.6% (76/352), 29.1% (102/350) and 39.7% (92/232) of the patients tested, respectively. Of 156 patients with confirmed TB, 65.4% were LAM positive. Of those classified as non-TB, 84.0% were LAM negative. Adding LAM increased the diagnostic yield of the algorithms by 36.6%, from 47.4% (95%CI:39.4–55.6) to 84.0% (95%CI:77.3–89.4%), when using clinical signs and X-ray; by 19.9%, from 62.2% (95%CI:54.1–69.8) to 82.1% (95%CI:75.1–87.7), when using clinical signs and microscopy; and by 13.4%, from 74.4% (95%CI:66.8–81.0) to 87.8% (95%CI:81.6–92.5), when using clinical signs and Xpert. LAM positive patients had an increased risk of 2-months mortality (aOR:2.7; 95%CI:1.5–4.9). Conclusion LAM should be included in TB diagnostic algorithms in parallel to microscopy or Xpert request for HIV-positive patients either ambulatory (severely ill or CD4<200cells/μl) or hospitalized. LAM allows same day treatment initiation in patients at higher risk of death and in those not able to produce sputum.
Collapse
|
20
|
Naidoo N, Pillay M. Bacterial pili, with emphasis on Mycobacterium tuberculosis curli pili: potential biomarkers for point-of care tests and therapeutics. Biomarkers 2016; 22:93-105. [PMID: 27797276 DOI: 10.1080/1354750x.2016.1252960] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
CONTEXT Novel biomarkers are essential for developing rapid diagnostics and therapeutic interventions Objective: This review aimed to highlight biomarker characterisation and assessment of unique bacterial pili. METHODS A PubMed search for bacterial pili, diagnostics, vaccine and therapeutics was performed, with emphasis on the well characterised pili. RESULTS In total, 46 papers were identified and reviewed. CONCLUSION Extensive analyses of pili enabled by advanced nanotechnology and whole genome sequencing provide evidence that they are strong biomarker candidates. Mycobacterium tuberculosis curli pili are emphasised as important epitopes for the development of much needed point-of-care diagnostics and therapeutics.
Collapse
Affiliation(s)
- Natasha Naidoo
- a Medical Microbiology and Infection Control , School of Laboratory Medicine and Medical Sciences, College of Health Science, University of KwaZulu-Natal, Congella , Durban , South Africa
| | - Manormoney Pillay
- a Medical Microbiology and Infection Control , School of Laboratory Medicine and Medical Sciences, College of Health Science, University of KwaZulu-Natal, Congella , Durban , South Africa
| |
Collapse
|
21
|
Hanifa Y, Fielding KL, Chihota VN, Adonis L, Charalambous S, Karstaedt A, McCarthy K, Nicol MP, Ndlovu NT, Sahid F, Churchyard GJ, Grant AD. Diagnostic Accuracy of Lateral Flow Urine LAM Assay for TB Screening of Adults with Advanced Immunosuppression Attending Routine HIV Care in South Africa. PLoS One 2016; 11:e0156866. [PMID: 27271432 PMCID: PMC4896615 DOI: 10.1371/journal.pone.0156866] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 05/19/2016] [Indexed: 12/03/2022] Open
Abstract
Background We assessed the diagnostic accuracy of Determine TB-LAM (LF-LAM) to screen for tuberculosis among ambulatory adults established in HIV care in South Africa. Methods A systematic sample of adults attending for HIV care, regardless of symptomatology, were enrolled in the XPHACTOR study, which tested a novel algorithm for prioritising investigation with Xpert MTB/RIF. In this substudy, restricted to participants with enrolment CD4<200x106/l, urine was stored at enrolment for later testing with LF-LAM. Sputum was sent for immediate Xpert MTB/RIF if any of: current cough, fever ≥3 weeks, body mass index (BMI)<18.5kg/m2, CD4<100x106/l (or <200x106/l if pre-ART), weight loss ≥10% or strong clinical suspicion were present; otherwise, sputum was stored for Xpert testing at study completion. Participants were reviewed monthly, with reinvestigation if indicated, to 3 months, when sputum and blood were taken for mycobacterial culture. We defined tuberculosis as “confirmed” if Xpert, line probe assay or culture for M. tuberculosis within six months of enrolment were positive, and “clinical” if tuberculosis treatment started without microbiological confirmation. Results Amongst 424 participants, 61% were female and 57% were taking ART (median duration 22 months); median age, CD4 and BMI were 39 years, 111x106/l, and 23 kg/m2. 56/424 (13%) participants had tuberculosis (40 confirmed, 16 clinical). 24/424 (5.7%) vs. 8/424 (1.9%) were LAM-positive using grade 1 vs. grade 2 cut-off. Using grade 1 cut-off, sensitivity for confirmed TB (all clinical TB excluded) was 12.5% (95% CI 4.2%, 26.8%) and in CD4<100x106/l vs. CD4 ≥100x106/l was 16.7% (95% CI 4.7%, 37.4%) vs. 6.3% (95% CI 0.2%, 30.2%). Specificity was >95% irrespective of diagnostic reference standard, CD4 stratum, or whether grade 1 or grade 2 cut-off was used. Conclusion Sensitivity of LF-LAM is too low to recommend as part of intensified case finding in ambulatory patients established in HIV care.
Collapse
Affiliation(s)
- Yasmeen Hanifa
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
| | | | - Violet N. Chihota
- Aurum Institute, Johannesburg, South Africa
- University of the Witwatersrand, Johannesburg, South Africa
| | | | - Salome Charalambous
- Aurum Institute, Johannesburg, South Africa
- University of the Witwatersrand, Johannesburg, South Africa
| | - Alan Karstaedt
- University of the Witwatersrand, Johannesburg, South Africa
- Department of Medicine, Chris Hani Baragwanath Hospital, Johannesburg, South Africa
| | | | - Mark P. Nicol
- National Health Laboratory Service, Johannesburg, South Africa
- University of Cape Town, Cape Town, South Africa
| | | | - Faieza Sahid
- University of the Witwatersrand, Johannesburg, South Africa
- Department of Medicine, Chris Hani Baragwanath Hospital, Johannesburg, South Africa
| | - Gavin J. Churchyard
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- Aurum Institute, Johannesburg, South Africa
- University of the Witwatersrand, Johannesburg, South Africa
- Advancing Care and Treatment (ACT) for TB/HIV, South African Medical Research Council Collaborating Centre for HIV and TB, Cape Town, South Africa
| | - Alison D. Grant
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- University of the Witwatersrand, Johannesburg, South Africa
| |
Collapse
|
22
|
Shah M, Hanrahan C, Wang ZY, Dendukuri N, Lawn SD, Denkinger CM, Steingart KR. Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in HIV-positive adults. Cochrane Database Syst Rev 2016; 2016:CD011420. [PMID: 27163343 PMCID: PMC4916932 DOI: 10.1002/14651858.cd011420.pub2] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Rapid detection of tuberculosis (TB) among people living with human immunodeficiency virus (HIV) is a global health priority. HIV-associated TB may have different clinical presentations and is challenging to diagnose. Conventional sputum tests have reduced sensitivity in HIV-positive individuals, who have higher rates of extrapulmonary TB compared with HIV-negative individuals. The lateral flow urine lipoarabinomannan assay (LF-LAM) is a new, commercially available point-of-care test that detects lipoarabinomannan (LAM), a lipopolysaccharide present in mycobacterial cell walls, in people with active TB disease. OBJECTIVES To assess the accuracy of LF-LAM for the diagnosis of active TB disease in HIV-positive adults who have signs and symptoms suggestive of TB (TB diagnosis).To assess the accuracy of LF-LAM as a screening test for active TB disease in HIV-positive adults irrespective of signs and symptoms suggestive of TB (TB screening). SEARCH METHODS We searched the following databases without language restriction on 5 February 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE (PubMed,1966); EMBASE (OVID, from 1980); Science Citation Index Expanded (SCI-EXPANDED, from 1900), Conference Proceedings Citation Index-Science (CPCI-S, from 1900), and BIOSIS Previews (from 1926) (all three using the Web of Science platform; MEDION; LILACS (BIREME, from 1982); SCOPUS (from 1995); the metaRegister of Controlled Trials (mRCT); the search portal of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); and ProQuest Dissertations & Theses A&l (from 1861). SELECTION CRITERIA Eligible study types included randomized controlled trials, cross-sectional studies, and cohort studies that determined LF-LAM accuracy for TB against a microbiological reference standard (culture or nucleic acid amplification test from any body site). A higher quality reference standard was one in which two or more specimen types were evaluated for TB, and a lower quality reference standard was one in which only one specimen type was evaluated for TB. Participants were HIV-positive people aged 15 years and older. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data from each included study using a standardized form. We appraised the quality of studies using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. We evaluated the test at two different cut-offs: (grade 1 or 2, based on the reference card scale of five intensity bands). Most analyses used grade 2, the manufacturer's currently recommended cut-off for positivity. We carried out meta-analyses to estimate pooled sensitivity and specificity using a bivariate random-effects model and estimated the models using a Bayesian approach. We determined accuracy of LF-LAM combined with sputum microscopy or Xpert® MTB/RIF. In addition, we explored the influence of CD4 count on the accuracy estimates. We assessed the quality of the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS We included 12 studies: six studies evaluated LF-LAM for TB diagnosis and six studies evaluated the test for TB screening. All studies were cross-sectional or cohort studies. Studies for TB diagnosis were largely conducted among inpatients (median CD4 range 71 to 210 cells per µL) and studies for TB screening were largely conducted among outpatients (median CD4 range 127 to 437 cells per µL). All studies were conducted in low- or middle-income countries. Only two studies for TB diagnosis (33%) and one study for TB screening (17%) used a higher quality reference standard.LF-LAM for TB diagnosis (grade 2 cut-off): meta-analyses showed median pooled sensitivity and specificity (95% credible interval (CrI)) of 45% (29% to 63%) and 92% (80% to 97%), (five studies, 2313 participants, 35% with TB, low quality evidence). The pooled sensitivity of a combination of LF-LAM and sputum microscopy (either test positive) was 59% (47% to 70%), which represented a 19% (4% to 36%) increase over sputum microscopy alone, while the pooled specificity was 92% (73% to 97%), which represented a 6% (1% to 24%) decrease from sputum microscopy alone (four studies, 1876 participants, 38% with TB). The pooled sensitivity of a combination of LF-LAM and sputum Xpert® MTB/RIF (either test positive) was 75% (61% to 87%) and represented a 13% (1% to 37%) increase over Xpert® MTB/RIF alone. The pooled specificity was 93% (81% to 97%) and represented a 4% (1% to 16%) decrease from Xpert® MTB/RIF alone (three studies, 909 participants, 36% with TB). Pooled sensitivity and specificity of LF-LAM were 56% (41% to 70%) and 90% (81% to 95%) in participants with a CD4 count of less than or equal to 100 cells per µL (five studies, 859 participants, 47% with TB) versus 26% (16% to 46%) and 92% (78% to 97%) in participants with a CD4 count greater than 100 cells per µL (five studies, 1410 participants, 30% with TB).LF-LAM for TB screening (grade 2 cut-off): for individual studies, sensitivity estimates (95% CrI) were 44% (30% to 58%), 28% (16% to 42%), and 0% (0% to 71%) and corresponding specificity estimates were 95% (92% to 97%), 94% (90% to 97%), and 95% (92% to 97%) (three studies, 1055 participants, 11% with TB, very low quality evidence). There were limited data for additional analyses.The main limitations of the review were the use of a lower quality reference standard in most included studies, and the small number of studies and participants included in the analyses. The results should, therefore, be interpreted with caution. AUTHORS' CONCLUSIONS We found that LF-LAM has low sensitivity to detect TB in adults living with HIV whether the test is used for diagnosis or screening. For TB diagnosis, the combination of LF-LAM with sputum microscopy suggests an increase in sensitivity for TB compared to either test alone, but with a decrease in specificity. In HIV-positive individuals with low CD4 counts who are seriously ill, LF-LAM may help with the diagnosis of TB.
Collapse
Affiliation(s)
- Maunank Shah
- John Hopkins University School of MedicineDepartment of Medicine, Division of Infectous DiseasesBaltimoreUSA
| | - Colleen Hanrahan
- Johns Hopkins Bloomberg School of Public HealthDepartment of Epidemiology615 N Wolfe StreetBaltimoreMarylandUSAMD 21205
| | - Zhuo Yu Wang
- McGill UniversityDepartment of Epidemiology, Biostatistics and Occupational HealthMontrealCanada
| | - Nandini Dendukuri
- McGill UniversityDepartment of Epidemiology, Biostatistics and Occupational HealthMontrealCanada
| | - Stephen D Lawn
- London School of Hygiene and Tropical MedicineDepartment of Clinical Research, Faculty of Infectious and Tropical DiseasesKeppel StreetLondonUKWC1E 7HT
| | | | - Karen R Steingart
- Liverpool School of Tropical MedicineCochrane Infectious Diseases GroupPembroke PlaceLiverpoolUK
| |
Collapse
|
23
|
Gupta-Wright A, Peters JA, Flach C, Lawn SD. Detection of lipoarabinomannan (LAM) in urine is an independent predictor of mortality risk in patients receiving treatment for HIV-associated tuberculosis in sub-Saharan Africa: a systematic review and meta-analysis. BMC Med 2016; 14:53. [PMID: 27007773 PMCID: PMC4804532 DOI: 10.1186/s12916-016-0603-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/17/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Simple immune capture assays that detect mycobacterial lipoarabinomannan (LAM) antigen in urine are promising new tools for the diagnosis of HIV-associated tuberculosis (HIV-TB). In addition, however, recent prospective cohort studies of patients with HIV-TB have demonstrated associations between LAM in the urine and increased mortality risk during TB treatment, indicating an additional utility of urinary LAM as a prognostic marker. We conducted a systematic review and meta-analysis to summarise the evidence concerning the strength of this relationship in adults with HIV-TB in sub-Saharan Africa, thereby quantifying the assay's prognostic value. METHODS We searched MEDLINE and Embase databases using comprehensive search terms for 'HIV', 'TB', 'LAM' and 'sub-Saharan Africa'. Identified studies were reviewed and selected according to predefined criteria. RESULTS We identified 10 studies eligible for inclusion in this systematic review, reporting on a total of 1172 HIV-TB cases. Of these, 512 patients (44 %) tested positive for urinary LAM. After a variable duration of follow-up of between 2 and 6 months, overall case fatality rates among HIV-TB cases varied between 7 % and 53 %. Pooled summary estimates generated by random-effects meta-analysis showed a two-fold increased risk of mortality for urinary LAM-positive HIV-TB cases compared to urinary LAM-negative HIV-TB cases (relative risk 2.3, 95 % confidence interval 1.6-3.1). Some heterogeneity was explained by study setting and patient population in sub-group analyses. Five studies also reported multivariable analyses of risk factors for mortality, and pooled summary estimates demonstrated over two-fold increased mortality risk (odds ratio 2.5, 95 % confidence interval 1.4-4.5) among urinary LAM-positive HIV-TB cases, even after adjustment for other risk factors for mortality, including CD4 cell count. CONCLUSIONS We have demonstrated that detectable LAM in urine is associated with increased risk of mortality during TB treatment, and that this relationship remains after adjusting for other risk factors for mortality. This may simply be due to a positive test for urinary LAM serving as a marker of higher mycobacterial load and greater disease dissemination and severity. Alternatively, LAM antigen may directly compromise host immune responses through its known immunomodulatory effects. Detectable LAM in the urine is an independent risk factor for mortality among patients receiving treatment for HIV-TB. Further research is warranted to elucidate the underlying mechanisms and to determine whether this vulnerable patient population may benefit from adjunctive interventions.
Collapse
Affiliation(s)
- Ankur Gupta-Wright
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, College of Medicine, University of Malawi, Blantyre, Malawi.
| | - Jurgens A Peters
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Clare Flach
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Stephen D Lawn
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
- The Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
24
|
Bates M, Zumla A. The development, evaluation and performance of molecular diagnostics for detection of Mycobacterium tuberculosis. Expert Rev Mol Diagn 2016; 16:307-22. [PMID: 26735769 DOI: 10.1586/14737159.2016.1139457] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The unique pathogenesis of tuberculosis (TB) poses several barriers to the development of accurate diagnostics: a) the establishment of life-long latency by Mycobacterium tuberculosis (M.tb) after primary infection confounds the development of classical antibody or antigen based assays; b) our poor understanding of the molecular pathways that influence progression from latent to active disease; c) the intracellular nature of M.tb infection in tissues means that M.tb and/or its components, are not readily detectable in peripheral specimens; and d) the variable presence of M.tb bacilli in specimens from patients with extrapulmonary TB or children. The literature on the current portfolio of molecular diagnostics tests for TB is reviewed here and the developmental pipeline is summarized. Also reviewed are data from recently published operational research on the GeneXpert MTB/RIF assay and discussed are the lessons that can be taken forward for the design of studies to evaluate the impact of TB diagnostics.
Collapse
Affiliation(s)
- Matthew Bates
- a UNZA-UCLMS Research & Training Programme , University Teaching Hospital , Lusaka , Zambia.,b Centre for Clinical Microbiology, Division of Infection and Immunity , University College London , London , UK
| | - Alimuddin Zumla
- a UNZA-UCLMS Research & Training Programme , University Teaching Hospital , Lusaka , Zambia.,b Centre for Clinical Microbiology, Division of Infection and Immunity , University College London , London , UK.,c NIHR Biomedical Research Centre , University College London Hospitals , London , UK
| |
Collapse
|
25
|
|
26
|
Linguissi LSG, Vouvoungui CJ, Poulain P, Essassa GB, Kwedi S, Ntoumi F. Diagnosis of smear-negative pulmonary tuberculosis based on clinical signs in the Republic of Congo. BMC Res Notes 2015; 8:804. [PMID: 26683052 PMCID: PMC4684611 DOI: 10.1186/s13104-015-1774-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 11/30/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The diagnosis of pulmonary tuberculosis (PTB) and smear-negative pulmonary tuberculosis (SNPT) in resource-limited countries is often solely based on clinical signs, chest X-ray radiography and sputum smear microscopy. We investigated currently used methods for the routine diagnosis of SNPT in the Republic of Congo (RoC) among TB suspected patients. The specific case of HIV positive patients was also studied. METHODS A cross-sectional study was conducted at the anti-tuberculosis center (CAT) of Brazzaville, RoC. Tuberculosis suspects were examined for physical signs of TB. Clinical signs, results from sputum smear microscopy, tuberculin skin test (TST) and chest X-ray were recorded. RESULTS Of the 772 enrolled participants, 372 were diagnosed PTB. Cough was a common symptom for PTB and no PTB patients. Pale skin, positive TST, weight loss and chest X-ray with abnormalities compatible with PTB (PTB-CXR) were significant indicators of PTB. Thirty-six percent of PTB patients were diagnosed SNPT. This category of patients presented less persistent cough and less PTB-CXR. Anorexia and asthenia were significant indicators of SNPT. In the case of HIV+ patients, 57% were SNPT with anorexia, asthenia and shorter cough being strong indicators of SNPT. CONCLUSION Chest X-ray abnormalities, weight loss, pale skin and positive TST were significant indicators of PTB. Anorexia and asthenia showed good diagnostic performance for SNPT, which deserve to be recommended as index indicators of SNPT diagnosis. Duration of cough is also a relevant indicator, especially for HIV+ patients.
Collapse
Affiliation(s)
- Laure Stella Ghoma Linguissi
- Fondation Congolaise pour la Recherche Médicale, Cité OMS, villa D6, Djoué, Brazzaville, Republic of Congo. .,Centre de Recherche Biomoleculaire Pietro Annigoni (CERBA), Labiogene, Université de Ouagadougou, 01 BP 364, Ouaga 01, Burkina Faso.
| | | | - Pierre Poulain
- Fondation Congolaise pour la Recherche Médicale, Cité OMS, villa D6, Djoué, Brazzaville, Republic of Congo. .,Institut National de la Santé et de la Recherche Médicale U 1134, Paris, France. .,UMR_S 1134, DSIMB, Université Paris Diderot, Sorbonne Paris Cite, Paris, France. .,Institut National de la Transfusion Sanguine, DSIMB, Paris, France. .,UMR_S 1134, Laboratory of Excellence GR-Ex, DSIMB, Paris, France.
| | - Gaston Bango Essassa
- Centre Antituberculeux de Brazzaville, Programme de Lutte contre la Tuberculose, Brazzaville, Republic of Congo.
| | - Sylvie Kwedi
- Capacity for Leadership Excellence and Research, CLEAR, INC, Yaoundé, Cameroon. .,Faculty of Médecine and Biomedical Sciences, University of Yaoundé I, Yaounde, Cameroon.
| | - Francine Ntoumi
- Fondation Congolaise pour la Recherche Médicale, Cité OMS, villa D6, Djoué, Brazzaville, Republic of Congo. .,Faculty of Sciences and Techniques, University Marien Ngouabi, BP 2672, Brazzaville, Republic of Congo. .,Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany.
| |
Collapse
|