Diagnostic accuracy of tests for leprosy: a systematic review and meta-analysis

Abstract

Objectives: Owing to difficulties in the clinical diagnosis of leprosy, several complementary tests have been developed and used. The aim was to systematically summarize the accuracy of diagnostic tests for leprosy. Methods: We searched for relevant articles in Embase, Medline, and Global Health databases, until June 2017. Studies evaluating the accuracy of any diagnostic techniques for differentiating between people with and without leprosy were included. Studies solely focusing on differentiating between the separate forms of leprosy were excluded. Our protocol was registered on PROSPERO (CRD42017071803). We assessed study quality using the QUADAS-2 checklist. A bivariate random effects regression model was used for the meta-analyses. Results: We included 78 studies, most of those evaluating the detection of IgM antibodies against phenolic glycolipid I using ELISA. Sensitivity of the 39 studies evaluating ELISA was 63.8% (95% CI 55.0 e71.8); specificity 91.0% (95% CI 86.9e93.9). The lateral flow test (nine studies) and the agglutination test (five studies) had a slightly higher sensitivity and a slightly lower specificity. Sensitivity of qPCR was (five studies) 78.5% (95% CI 61.9e89.2) and specificity 89.3% (95% CI 61.4e97.8). Sensitivity of conventional PCR was (17 studies) 75.3% (95% CI 67.9e81.5) and specificity 94.5% (95% CI 91.4e96.5). Conclusions: Although the test accuracy looks reasonable, the studies suffered from heterogeneity and low methodological quality.

The accuracy of the Montenegro skin test for leishmaniasis in PCR-negative patients

“…A maximum sensitivity of 75% for PCR and 90% for MST may seem insufficient for field diagnosis, but this result is in line with previous studies conducted in this geographical region 7,8 . It is also important to remember that cross-sectional accuracy studies result in reduced sensitivity values as compared to other methodologies conducted in well-controlled enviroments 8,19,20 .…”

T Cell Responses to Mycobacterial Glycolipids: On the Spectrum of “Innateness”

“…High-affinity IgG antibodies targeting LAM have been incorporated into a urinebased assay for TB and have shown clinical utility in the setting of HIV co-infection (94). IgM antibodies targeting phenolic glycolipids (PGLs) are being used for the diagnosis of leprosy (95). Even though the current standard for leprosy diagnosis incorporates IgM antibodies to PGL, this could improve as PGLs also likely contain T cell epitopes, which could be leveraged to develop higher affinity IgG antibodies to PGLs.…”

Leprosy incidence and risk estimates in a 33-year contact cohort of leprosy patients

“…A meta-analysis study regarding the accuracy of ELISAs in detecting antibodies against mycobacterium leprae concluded that traditional ELISAs have good accuracy in detecting MB leprosy and poor accuracy in detecting PB leprosy 40 . Another meta-analysis evaluating diagnostic accuracy of tests concluded that although the test accuracy looks reasonable, the studies suffered from heterogeneity and low methodological quality 41 .…”