Diagnostic accuracy of leptospirosis whole-cell lateral flow assays: a systematic review and meta-analysis

Citation: 
Michael J.MazeMB ChB1Katrina J.SharplesPhD2Kathryn J.AllanPhD3Matthew P.RubachMD4John A.CrumpMD5 1 Centre for International Health, University of Otago, New Zealand; Department of Medicine, University of Otago, Christchurch, New Zealand and Kilimanjaro Christian Medical Centre, Moshi, Tanzania 2 Department of Mathematics and Statistics, University of Otago, Dunedin, New Zealand 3 Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom 4 Kilimanjaro Christian Medical Centre, Moshi, Tanzania; Division of Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America; Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America 5 Centre for International Health, University of Otago, Dunedin, New Zealand; Kilimanjaro Christian Medical Centre, Moshi, Tanzania; Division of Infectious Diseases, Duke University Medical Center, Durham, North Carolina, United States of America; Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America
Publication year: 
2018

Background

Leptospirosis is under-diagnosed by clinicians in many high-incidence countries, as reference diagnostic tests are largely unavailable. Lateral flow assays (LFA) that use antigen derived from heat-treated whole cell Leptospira biflexa serovar Patoc have potential to improve leptospirosis diagnosis in resource-limited settings.

Objectives

We sought to summarize estimates of sensitivity and specificity of LFA by conducting a systematic review and meta-analysis of evaluations of the accuracy of LFA to diagnose human leptospirosis.

Data sources

On 4 July 2017 we searched three medical databases.

Study eligibility criteria

Articles were included if they were a study of LFA sensitivity and specificity

Participants

Patients with suspected leptospirosis

Interventions

Nil

Methods

For included articles, we assessed study quality, characteristics of participants, and diagnostic testing methods. We estimated sensitivity and specificity for each study against the study-defined case definition as the reference standard, and performed a meta-analysis using a random-effects bivariate model.

Results

Our search identified 225 unique reports, of which we included nine (4%) published reports containing 11 studies. We classified one (9%) study as high quality. Nine (82%) studies used reference tests with considerable risk of misclassification. Our pooled estimates of sensitivity (95% confidence intervals) were 79% (70,86%) and specificity 92% (85,96%).

Conclusions

As the evidence base for determining the accuracy of LFA is small and at risk of bias, pooled estimates of sensitivity and specificity should be interpreted with caution. Further studies should use either reference tests with high sensitivity and specificity or statistical techniques that account for an imperfect reference standard.