Diagnostic accuracy of a urine lipoarabinomannan strip-test for TB detection in HIV-infected hospitalised patients
Open Access
- 23 February 2012
- journal article
- clinical trial
- Published by European Respiratory Society (ERS) in European Respiratory Journal
- Vol. 40 (5), 1211-1220
- https://doi.org/10.1183/09031936.00201711
Abstract
Lack of point-of-care tests for tuberculosis (TB) result in diagnostic delay, and increased mortality and healthcare-related costs. The urine DetermineTM TB-LAM point-of-care strip-test was evaluated in 335 prospectively-recruited hospitalised patients with suspected TB-HIV co-infection (group 1) and from 88 HIV-infected hospitalised patients with non-TB diagnoses (group 2). Cut-off point-specific analyses were performed using: 1) a microbiological reference standard (culture positive versus negative); and 2) a composite reference standard (exclusion of patients with clinical-TB from the culture-negative group). Using the microbiological reference and the manufacturer-recommended grade-1 cut-off point, LAM sensitivity and specificity was 66% (95% CI 57–74%). By contrast, using the composite reference sensitivity was 60% (95% CI 53–67%) and specificity improved to 96% (95% CI 89–100%) (p=0.001). The same pattern was seen when the grade-2 cut-off point was used (specificity 75% versus 96%; p=0.01). In group two patients specificity was poor using the grade-1 cut-off point, but improved significantly when the grade-2 cut-off point was used (90% versus 99%; p=0.009). The grade-2 cut-off point also offered superior inter-reader reliability (p=0.002). Sensitivity was highest in those with a CD4 Mycobacterium tuberculosis culture-positive patients. This preliminary study indicates that the LAM strip-test may be a potentially useful rapid rule-in test for TB in hospitalised patients with advanced immunosuppression. The grade 2, but not the manufacturer-recommended grade 1 cut-off point, offered superior rule-in utility and inter-reader reliability. Larger studies to evaluate cut-off points and diagnostic accuracy are urgently required.Keywords
This publication has 19 references indexed in Scilit:
- Diagnostic accuracy of a low-cost, urine antigen, point-of-care screening assay for HIV-associated pulmonary tuberculosis before antiretroviral therapy: a descriptive studyThe Lancet Infectious Diseases, 2012
- Lipoarabinomannan and related glycoconjugates: structure, biogenesis and role inMycobacterium tuberculosisphysiology and host–pathogen interactionFEMS Microbiology Reviews, 2011
- Systematic Review and Meta-Analysis of Antigen Detection Tests for the Diagnosis of TuberculosisClinical and Vaccine Immunology, 2011
- Diagnostic Accuracy of a Urine Lipoarabinomannan Enzyme-Linked Immunosorbent Assay for Screening Ambulatory HIV-Infected Persons for TuberculosisJAIDS Journal of Acquired Immune Deficiency Syndromes, 2011
- Use of a WHO-recommended algorithm to reduce mortality in seriously ill patients with HIV infection and smear-negative pulmonary tuberculosis in South Africa: an observational cohort studyThe Lancet Infectious Diseases, 2011
- Diagnosing tuberculosis with urine lipoarabinomannan: systematic review and meta-analysisEuropean Respiratory Journal, 2011
- The Prevalence and Drug Sensitivity of Tuberculosis among Patients Dying in Hospital in KwaZulu-Natal, South Africa: A Postmortem StudyPLoS Medicine, 2010
- An Algorithm for Tuberculosis Screening and Diagnosis in People with HIVThe New England Journal of Medicine, 2010
- Yield of Acid-fast Smear and Mycobacterial Culture for Tuberculosis Diagnosis in People with Human Immunodeficiency VirusAmerican Journal of Respiratory and Critical Care Medicine, 2009
- Diagnostic Accuracy of a Urine Lipoarabinomannan Test for Tuberculosis in Hospitalized Patients in a High HIV Prevalence SettingJAIDS Journal of Acquired Immune Deficiency Syndromes, 2009