Serological studies on shistosomiasis mansoni in the Northeast Brasil

Abstract

Sera from the patients (N = 10) with schistosomiasis mansoni of the hospital of Federal University of Pernambuco, the Schistosoma mansoni egg-positive (N = 51) and -negative (N = 452) inhabitants in Cabo City area, out-patients (N = 37) of the IMIP hospital and Japanese immigrants (N = 127) in Petrolina City area of northeast Brazil as well as Japanese healthy subjects (N = 30) were examined by serological tests including an enzyme-linked immunosorbent assay with antigens prepared from eggs (ELISA-egg) and adult worms (ELISA-adult). The ELISA with egg or adult antigen correctly identified 100% of the uninfected individuals lived in non-endemic area of schistosomiasis. Moreover, when examined cross-reactivity of our ELISA with sera isolated from 78 subjects infected with various intestinal parasitic infections, only one of these sera reacted with the egg and adult antigens. On the examination of 51 sera from the egg-positive subjects, the ELISA-egg revealed the highest sensitivity (98.0%), whereas a large number of false negative reactions of ELISA-adult, Ouchterlony method using adult antigen, circumoval precipitation and immediate intradermal skin test were observed. A low sensitivity of these serologic tests except for ELISA-egg appears to be primarily due to their inability to detect antibody in the sera from egg-positive infantiles. There was no positive correlation between the absorbance values of these two types of ELISA among the sera isolated from ELISA-positive subjects. Rather, by the reactivity of these sera to egg or adult antigen, they could be divided into two subgroups; one reacted more positively with egg antigen and the other with adult antigen. Moreover, it was confirmed that the sera from young subjects (under 20 years old) appear to be highly reactive to the egg antigen than did aged ones. These data suggest that the ELISA with egg antigen, but not with the adult antigen, appears to be useful for the serological survey of schistosomiasis mansoni in the endemic area of northeast Brazil.

Seroprevalence of schistosomiasis in African patients infected with HIV

“…From March 2005, all HIV‐positive patients of sub‐Saharan African origin attending our department were tested for the presence of schistosomal antibodies in serum using an enzyme‐linked immunosorbent assay (ELISA), employing an unfractionated, water‐soluble extract of S. mansoni egg antigen (SEA/ELISA) [8,9] which detects immunoglobulin G antibodies to both S. mansoni and S. haematobium with high sensitivity and specificity and minimal cross‐reactivity to other helminths or internal parasites [10,11]. The method is currently used in all UK accredited clinical parasitology diagnostic laboratories (Clinical Pathology Association UK Accreditation) and has been validated against an indirect haemagglutination test using S. mansoni adult worm antigen (WA/IHA) [10] and against egg counts in an area of high endemicity [12].…”

Prevalence of Toxocariasis in Northeastern Brazil Based on Serology Using Recombinant Toxocara Canis Antigen

“…It has also been reported that schistosomiasis mansoni is still endemic in the surrounding district. 28,29 Human serum samples. Serum samples were collected from 215 children (age range ‫ס‬ 1−17 years), after informed consent was obtained, for epidemiologic and clinical surveys on helminth infections.…”

ELISA-IgM para diagnóstico da esquistossomose mansoni em área de baixa endemicidade

“…Entretanto, sua utilização no nosso meio é ainda muito limitada, devido sobretudo à falta de reagentes comerciais aplicáveis ao diagnóstico da esquistossomose. Variantes técnicas têm sido empregadas para detecção de anticorpos contra antígenos de vermes adultos (Sathe et al, 1991;Silva et al, 1998;Valli et al, 1997) ou de ovos (Doenhoff et al, 1993;Eltiro et al, 1992;Kamal et al, 1994;Tanabe et al, 1990), de Schistosoma mansoni (Sambon, 1907). No entanto, alguns pesquisadores verificaram a presença de reações cruzadas em amostras de soro de indivíduos infestados com outros parasitas que não o S. mansoni, quando se utiliza extrato total como antígeno no método de ELISA e Western-blot para pesquisa de anticorpos IgG (Correia-Oliveira et al, 1988;Valli et al, 1997).…”