LSTM Home > LSTM Research > LSTM Online Archive

The Sensitivity and Specificity of Loop-Mediated Isothermal Amplification (LAMP) Assay for Tuberculosis Diagnosis in Adults with Chronic Cough in Malawi

Downloads

Downloads per month over past year

Fernandez-Reyes, Delmiro, Nliwasa, Marriott, MacPherson, Peter ORCID: https://orcid.org/0000-0002-0329-9613, Chisala, Palesa, Kamdolozi, Mercy, Khundi, McEwen, Kaswaswa, Kruger, Mwapasa, Mphatso, Msefula, Chisomo, Sohn, Hojoon, Flach, Clare and Corbett, Elizabeth L. (2016) 'The Sensitivity and Specificity of Loop-Mediated Isothermal Amplification (LAMP) Assay for Tuberculosis Diagnosis in Adults with Chronic Cough in Malawi'. PLoS ONE, Vol 11, Issue 5, e0155101.

[img]
Preview
Text
PLoS_One_11_5_e0155101_The Sensitivity and Specificity of LAMP.PDF - Published Version
Available under License Creative Commons Attribution.

Download (836kB) | Preview

Abstract

Background
Current tuberculosis diagnostics lack sensitivity, and are expensive. Highly accurate, rapid and cheaper diagnostic tests are required for point of care use in low resource settings with high HIV prevalence.

Objective
To investigate the sensitivity and specificity, and cost of loop-mediated isothermal amplification (LAMP) assay for tuberculosis diagnosis in adults with chronic cough compared to Xpert® MTB/RIF, fluorescence smear microscopy.

Methods
Between October 2013 and March 2014, consecutive adults at a primary care clinic were screened for cough, offered HIV testing and assessed for tuberculosis using LAMP, Xpert® MTB/RIF and fluorescence smear microscopy. Sensitivity and specificity (with culture as reference standard), and costs were estimated.

Results
Of 273 adults recruited, 44.3% (121/273) were HIV-positive and 19.4% (53/273) had bacteriogically confirmed tuberculosis. The sensitivity of LAMP compared to culture was 65.0% (95% CI: 48.3% to 79.4%) with 100% (95% CI: 98.0% to 100%) specificity. The sensitivity of Xpert® MTB/RIF (77.5%, 95% CI: 61.5% to 89.2%) was similar to that of LAMP, p = 0.132. The sensitivity of concentrated fluorescence smear microscopy with routine double reading (87.5%, 95% CI: 73.2% to 95.8%) was higher than that of LAMP, p = 0.020. All three tests had high specificity. The lowest cost per test of LAMP was at batch size of 14 samples (US$ 9.98); this was lower than Xpert® MTB/RIF (US$ 13.38) but higher than fluorescence smear microscopy (US$ 0.65).

Conclusion
The sensitivity of LAMP was similar to Xpert® MTB/RIF but lower than fluorescence smear microscopy; all three tests had high specificity. These findings support the Malawi policy that recommends a combination of fluorescence smear microscopy and Xpert® MTB/RIF prioritised for people living with HIV, already found to be smear-negative, or being considered for retreatment of tuberculosis.

Item Type: Article
Subjects: WA Public Health > Health Problems of Special Population Groups > WA 395 Health in developing countries
WB Practice of Medicine > Diagnosis > General Diagnosis > WB 141 General works
WC Communicable Diseases > Virus Diseases > Acquired Immunodeficiency Syndrome. HIV Infections > WC 503 Acquired immunodeficiency syndrome. HIV infections
WC Communicable Diseases > Virus Diseases > Acquired Immunodeficiency Syndrome. HIV Infections > WC 503.5 Complications
WF Respiratory System > Tuberculosis > WF 200 Tuberculosis (General)
WF Respiratory System > Tuberculosis > WF 220 Diagnosis. Prognosis
Faculty: Department: Clinical Sciences & International Health > Clinical Sciences Department
Digital Object Identifer (DOI): https://doi.org/10.1371/journal.pone.0155101
Depositing User: Jessica Jones
Date Deposited: 16 May 2016 08:43
Last Modified: 06 Feb 2018 13:12
URI: https://archive.lstmed.ac.uk/id/eprint/5886

Statistics

View details

Actions (login required)

Edit Item Edit Item