Immunoassays as an auxiliary tool for the serodiagnosis of Schistosoma mansoni infection in individuals with low intensity of egg elimination

Acta Trop. 2006 Nov;100(1-2):24-30. doi: 10.1016/j.actatropica.2006.09.004. Epub 2006 Oct 27.

Abstract

In an attempt to improve the screening of Schistosoma mansoni-infected individuals from a low-transmission area, we established a protocol that includes three independent coproscopy examinations and two serological assays. Three stool samples were examined using the Kato-Katz and free sedimentation methods and serum samples were tested by IgG-ELISA and IgM-immunofluorescence. Two hundred and sixty-nine individuals participated in the survey: 132 individuals (49%) showed positive serological test results. Of these, 16 (6%) had positive results in stool examination in the first sample batch. However, there were also cases with positive serological test results in spite of negative Kato-Katz stool examinations. Additional stool samples were obtained from these subjects and in this way an additional 11 egg-excretors were found. Our findings suggest that a screening method that combines antibody isotype detection and repeated parasitological stool examinations could increase the chances of detecting S. mansoni-infected patients.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Helminth / blood*
  • Antigens, Helminth / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Feces / parasitology*
  • Fluorescent Antibody Technique
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Parasite Egg Count*
  • Schistosoma mansoni / growth & development
  • Schistosoma mansoni / immunology*
  • Schistosoma mansoni / isolation & purification
  • Schistosomiasis mansoni / diagnosis*
  • Schistosomiasis mansoni / parasitology
  • Serologic Tests

Substances

  • Antibodies, Helminth
  • Antigens, Helminth
  • Immunoglobulin G
  • Immunoglobulin M