title: Comparison of two rapid tests for anti-phenolic glycolipid-I serology in Brazil and Nepal.
abstract: The diagnosis of leprosy continues to be based on clinical symptoms and early diagnosis and treatment are critical to preventing disability and transmission. Sensitive and specific laboratory tests are not available for diagnosing leprosy. Despite the limited applicability of anti-phenolic glycolipid-I (PGL-I) serology for diagnosis, it has been suggested as an additional tool to classify leprosy patients (LPs) for treatment purposes. Two formats of rapid tests to detect anti-PGL-I antibodies [ML immunochromatography assay (ICA) and ML Flow] were compared in different groups, multibacillary patients, paucibacillary patients, household contacts and healthy controls in Brazil and Nepal. High ML Flow intra-test concordance was observed and low to moderate agreement between the results of ML ICA and ML Flow tests on the serum of LPs was observed. LPs were "seroclassified" according to the results of these tests and the seroclassification was compared to other currently used classification systems: the World Health Organization operational classification, the bacilloscopic index and the Ridley-Jopling classification. When analysing the usefulness of these tests in the operational classification of PB and MB leprosy for treatment and follow-up purposes, the ML Flow test was the best point-of-care test for subjects in Nepal and despite the need for sample dilution, the ML ICA test yielded better performance among Brazilian subjects. Our results identified possible ways to improve the performance of both tests.
authors.affiliation: Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brasil.
authors.forename: Mariane Martins de Araújo
authors.initials: MM
authors.lastname: Stefani
authors.forename: Adriano Badotti
authors.initials: AB
authors.lastname: Grassi
authors.forename: Lucas Henrique
authors.initials: LH
authors.lastname: Sampaio
authors.forename: Ana Lúcia Osório Maroclo de
authors.initials: AL
authors.lastname: Sousa
authors.forename: Maurício Barcelos
authors.initials: MB
authors.lastname: Costa
authors.forename: Pauline
authors.initials: P
authors.lastname: Scheelbeek
authors.forename: Kapil D
authors.initials: KD
authors.lastname: Neupane
authors.forename: Deanna A
authors.initials: DA
authors.lastname: Hagge
authors.forename: Murdo
authors.initials: M
authors.lastname: Macdonald
authors.forename: Sang-Nae
authors.initials: SN
authors.lastname: Cho
authors.forename: Linda
authors.initials: L
authors.lastname: Oskam
authors.forename: Samira
authors.initials: S
authors.lastname: Bührer-Sékula
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000097:blood*; D001938:Brazil; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002846:Chromatography, Affinity / Q000379:methods; D005260:Female; D006017:Glycolipids / Q000097:blood*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007132:Immunoglobulin Isotypes / Q000097:blood*; D007918:Leprosy / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009166:Mycobacterium leprae / Q000276:immunology*; D009390:Nepal; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D006017:Glycolipids; D007132:Immunoglobulin Isotypes; D011933:Reagent Kits, Diagnostic; C045169:phenolic glycolipid I, Mycobacterium leprae