|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.|
|Publication Type||Journal Article|
|Authors||Frota CC, Freitas MVC, Foss NT, Lima LNC, Rodrigues LC, Barreto ML, Kerr LRS|
|Abbrev. Journal||Trans. R. Soc. Trop. Med. Hyg.|
|Journal||Transactions of the Royal Society of Tropical Medicine and Hygiene|
|Year of Publication||2010|
|Keywords||Adolescent, Adult, Aged, Aged, 80 and over, Antibodies, Bacterial, Antigens, Bacterial, Biomarkers, Brazil, Contact Tracing, Cross-Sectional Studies, Enzyme-Linked Immunosorbent Assay, Female, Glycolipids, Humans, Immunoglobulin M, Leprosy, Leprosy, Lepromatous, Leprosy, Tuberculoid, Male, Middle Aged, Seroepidemiologic Studies, Young Adult|
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.