Feasibility of using Determine TB-LAM to diagnose tuberculosis in HIV-positive patients in programmatic conditions: a multisite study

ABSTRACT

Background: Determine TB-LAM is a urine-based point-of-care assay for diagnosis of tuberculosis (TB).

Objective: To assess the feasibility of using LAM to diagnose TB in adult HIV-positive patients in resource-limited settings.

Methods: We performed a multi-centric mixed-methods cross-sectional descriptive study in the Democratic Republic of Congo, Malawi, and Mozambique. We used the study and program monitoring tools to estimate user workload, turn-around time (TAT), and proportion of patients with LAM and sputum-based results. We conducted semi-structured interviews to assess the user acceptability of the LAM.

Results: The duration of the LAM testing activity per patient was 27 min (IQR 26–29); staff continued with other duties whilst waiting for the result. More patients had a LAM versus a sputum-based result: 168/213 (78.9%) vs 77/213 (36.1%), p < 0.001 in DRC; 691/695 (99.4%) vs 429/695 (61.7%), p < 0.001 in Malawi; and 646/647 (99.8%) vs 262/647 (40.5%), p < 0.001 in Mozambique. The median TAT in minutes when LAM was performed in the consultation room was 75 (IQR 45–188) in DRC, 29 (IQR 27–39) in Malawi, and 36 (IQR 35–41) in Mozambique. In comparison, the overall median TAT for sputum-based tests (smear or GeneXpert) was 2 (IQR 1–3) days. The median time to the first anti-TB drug dose for LAM-positive patients was 155 (IQR 90–504) minutes in DRC and 90 (IQR 60–117) minutes in Mozambique. The overall inter-reader agreement for the interpretation of the LAM result as positive or negative was 98.9%, kappa 0.97 (95%CI 0.96–0.99). Overall, LAM users found the test easy to perform. Major concerns were use of the reading card and the prior requirement of CD4 results before LAM testing.

Conclusion: It is feasible to implement the LAM test in low resource settings. The short TAT permitted same day initiation of TB treatment for LAM-positive patients.

KEYWORDS:

• Lipoarabinomannan
• implementation
• tuberculosis
• diagnosis
• low income settings

Responsible Editor Jennifer Stewart Williams, Umeå University, Sweden

Responsible Editor Jennifer Stewart Williams, Umeå University, Sweden

Acknowledgments

The authors would like to thank the staff and patients from all the participating sites. Special thanks to Elisabeth Sanchez-Padilla for her suggestions, and critical review of the article, to Rose Burns for her input related to the qualitative aspects of the article and to Emily Lynch for editing the text.

Disclosure statement

No potential conflict of interest was reported by the authors.

Ethics and consent

Ethics approval was granted by the MSF Ethics Review Board (Protocol number 1845) in DRC, the National Research Committee of Malawi (Protocol number 850), and the Mozambique Ethics Board, (Protocol number 1422).

Paper context

In 2015, the Determine TB-LAM test was recommended as a tuberculosis diagnosis tool among HIV positive people. The accuracy of the test has been assessed in several studies, but there are still knowledge gaps related to its practical implementation. Our paper discusses the benefits and bottlenecks identified during programmatic implementation of the LAM test. These findings can guide policymakers and program managers as they consider wider use of the LAM test outside of study settings.

Additional information

Funding

Funding for this study was provided by Médecins Sans Frontières.

Notes on contributors

Sekai Chenai Mathabire Rucker

SCMR and HH designed the study protocols. SCMR, REH, LC coordinated the data collection and cleaning. SCMR and HH performed the data analysis and drafted the research manuscript. LC, REH, JM, SL, PKK, FMK, IAQ, LM, ES, OT, and ZN, critically revised the protocol, abstract and paper for content.