title: Seropositivity to anti-phenolic glycolipid-I in leprosy cases, contacts and no known contacts of leprosy in an endemic and a non-endemic area in northeast Brazil.
abstract: The seroprevalence rates of IgM anti-phenolic glycolipid-I (PGL-I) antibodies in four study groups with differing exposure to Mycobacterium leprae in Ceará, Brazil were investigated between March 2005 and August 2006. The first three groups in a high prevalence area included 144 cases of leprosy, their 380 contacts and 317 participants with no known leprosy contact. The fourth group in a low prevalence area consisted of 87 participants with no known leprosy contact living in an area in which no cases of leprosy had been reported in the previous 6 months. Seropositivity and levels of IgM antibodies to PGL-I were investigated using ELISA. The seropositivity levels of anti-PGL-I among the different clinical forms of leprosy cases were 61% for lepromatous, 25% for tuberculoid and 27% indeterminate. The levels of anti-PGL-I antibodies in the endemic area differentiated leprosy cases from non-cases. However, the seropositivity was similar among contact cases (15.8%) and no known leprosy contact cases from high (15.1%) and low (13.8%) prevalence areas. The seropositivity of both contacts and no known contacts was much higher than previously reported among no known contacts in other endemic areas. The study indicates that anti-PGL-I antibodies are not useful as immunological markers of household leprosy contacts and no known leprosy contacts in endemic areas.
authors.affiliation: Departamento de Patologia, Faculdade de Medicina, Federal University of Ceará, Fortaleza, CE, Brazil. ccfrota@hotmail.com
authors.forename: Cristiane C
authors.initials: CC
authors.lastname: Frota
authors.forename: Max V C
authors.initials: MV
authors.lastname: Freitas
authors.forename: Norma T
authors.initials: NT
authors.lastname: Foss
authors.forename: Luana N C
authors.initials: LN
authors.lastname: Lima
authors.forename: Laura C
authors.initials: LC
authors.lastname: Rodrigues
authors.forename: Maurício L
authors.initials: ML
authors.lastname: Barreto
authors.forename: Ligia R S
authors.initials: LR
authors.lastname: Kerr
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D016358:Contact Tracing; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006017:Glycolipids / Q000276:immunology*; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood* / Q000276:immunology; D007918:Leprosy / Q000097:blood / Q000453:epidemiology / Q000276:immunology*; D015440:Leprosy, Lepromatous / Q000097:blood / Q000453:epidemiology / Q000276:immunology; D015441:Leprosy, Tuberculoid / Q000097:blood / Q000453:epidemiology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D015415:Biomarkers; D006017:Glycolipids; D007075:Immunoglobulin M; C045169:phenolic glycolipid I, Mycobacterium leprae