Serum pretreatment with Schistosoma mansoni antigens for serological diagnosis of fascioliasis.
Cross-reactivity between Fasciola and Schistosoma often causes false positive results in serological assays for diagnosis of fascioliasis. The authors tried to reduce cross-reactivity in ELISA for diagnosis of fascioliasis by preincubation of serum samples with a mixture of Schistosoma mansoni adult worm and egg antigens. This method was evaluated using serum samples from 4 groups: 25 patients infected with Fasciola, 40 healthy controls, 113 patients infected with S. mansoni and a group of 100 patients with suspected Fasciola infection. In group with confirmed Fasciola infection, the sensitivity of ELISA was 96% without any change after serum pretreatment while, in control group, the specificity was elevated from 90% to 97.5% after serum pretreatment with S. mansoni antigens. In S. mansoni infection and suspected Fasciola infection groups, there was a highly significant reduction in number of ELISA positive cases after serum pretreatment with S. mansoni antigens (McNemar P < 0.001 for each). In logistic regression model, seroconversion showed significant dependence on presence of S. mansoni infection (P = 0.012). The probability of seroconversion was more than three times higher in S. mansoni infected individuals than in non-infected ones (Odds ratio = 3.5).
Noureldin
M S
MS
Department of Parasitology, Faculty of Medicine, Mansoura University, Egypt.
el-Shinnawy
H
H
Abou Elenin
A
A
D000293:Adolescent; D000328:Adult; D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005211:Fascioliasis / Q000175:diagnosis*; D006801:Humans; D012550:Schistosoma mansoni / Q000276:immunology*
D000947:Antigens, Helminth