title: Use of the anti-PGL-I antibody ELISA and the Mitsuda reaction in early diagnosis of leprosy.
abstract: Cutaneous reaction to the Mitsuda antigen and anti-PGL-I IgM antibodies (ELISA) were determined in 134 leprosy patients, 290 household contacts, 52 healthy controls and 43 tuberculous individuals. The multibacillary patients did not develop cell-mediated immunity (CMI), although they presented high levels of IgM (absorbance at 492 nm greater than 0.5). The paucibacillary patients presented CMI, although in varying degrees, and IgM levels did not exceed 0.5 absorbance units. Most of the contacts (107) showed a Mitsuda-positive test, and 25 of them were anti-PGL-I IgM seropositive (absorbance less than 0.5 but greater than 0.22), although none became ill during the two-year follow-up. Of the 17 Mitsuda-negative contacts, two exhibited an immunological status of lepromatous leprosy (negative Mitsuda test and positive serology; absorbance greater than 0.5) and became ill (one borderline lepromatous and one indeterminate leprosy). These results show that the immunological status of lepromatous leprosy can appear prior to clinical symptoms, and thus serology for anti-PGL-I IgM together with the Mitsuda test can be useful in an active search for new preclinical cases among high risk populations.
authors.affiliation: Setor de Hanseníase, Fundação Oswaldo Cruz, Rio de Janeiro, Brasil.
authors.forename: M H
authors.initials: MH
authors.lastname: Saad
authors.forename: M A
authors.initials: MA
authors.lastname: Medeiros
authors.forename: M E
authors.initials: ME
authors.lastname: Gallo
authors.forename: L S
authors.initials: LS
authors.lastname: Fonseca
mesh_terms: D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D006017:Glycolipids; D006801:Humans; D007111:Immunity, Cellular; D007075:Immunoglobulin M / Q000032:analysis; D007918:Leprosy / Q000175:diagnosis*; D009166:Mycobacterium leprae / Q000276:immunology*; D012882:Skin Tests
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D006017:Glycolipids; D007075:Immunoglobulin M; C045169:phenolic glycolipid I, Mycobacterium leprae