Title
Evaluation of the diagnostic performance of laboratory-based c-reactive protein as a triage test for active pulmonary tuberculosis
Date Issued
01 July 2021
Access level
open access
Resource Type
journal article
Author(s)
London School of Hygiene and Tropical Medicine
Publisher(s)
Public Library of Science
Abstract
Introduction A highly sensitive triage test that captures most symptomatic patients at increased likelihood of having pulmonary tuberculosis (PTB) would 'rule-out' lower-risk patients from expensive confirmatory testing. Although studies have assessed the diagnostic accuracy of a C-reactive protein (CRP) triage test for PTB in HIV+ patients, limited data are available from HIVcohorts. Materials and methods In this retrospective case-control study, 765 serum samples were selected from FIND's biobank. Each sample had been collected from an adult presenting with respiratory symptomatology to district hospitals in South Africa and referral hospitals in Cambodia, Peru, Georgia and Vietnam between 2007-2017. Serum CRP measurements were obtained using a laboratory-based assay. CRP cutoff-points of ≥8mg/L and ≥10mg/L were predefined as a positive triage test result. The PTB reference standard was two contemporaneously collected sputum liquid culture results. Results CRP demonstrated an overall sensitivity for PTB of 79.8% (95%CI 75.5-83.5) and 77.7% (95%CI 73.4-81.6) for cutoff-points of 8mg/L and 10mg/L respectively. Specificity was 62.8% (95%CI 57.8-67.6%) and 66.6% (95%CI 61.1-70.7) respectively. Area-under-thecurve using Receiver Operating Characteristic analysis was 0.77 (95%CI 0.74-0.81). Threshold analysis showed optimal CRP cutoff-points were higher in HIV+ than HIV- participants. An algorithm in which CRP triage was followed by confirmatory Xpert MTB/Rif testing achieved a sensitivity of 75.1% (95%CI 69.0-80.4%) whilst decreasing Xpert usage by 40.6%. Discussion CRP may not meet the challenge of a catch-all TB triage test. However, it shows promise in HIV+ individuals. Further research is required in a prospective study using point-of-care platforms to further evaluate its capabilities.
Volume
16
Issue
7 July
Number
e0254002
Language
English
OCDE Knowledge area
Sistema respiratorio
Epidemiología
Inmunología
Salud pública, Salud ambiental
Scopus EID
2-s2.0-85109769774
PubMed ID
Source
PLoS ONE
ISSN of the container
19326203
Sponsor(s)
Ministerie van Buitenlandse Zaken - PDP15CH14
This work was funded by the UK Department for International Development (DFID) grant number 300341-102 (https://www.gov.uk/ government/organisations/department-forinternational- development), Dutch Ministry of Foreign Affairs grant number PDP15CH14 (https:// www.government.nl/ministries/ministry-of-foreignaffairs), Australian Department of Foreign Affairs and Trade (DFAT) grant number 70957 (https:// www.dfat.gov.au/). CD received all awarded funding. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Sources of information:
Directorio de Producción Científica
Scopus