Low avidity IgG antibodies in diagnosis of recent human schistosomiasis

J Egypt Soc Parasitol. 2002 Dec;32(3):979-85.

Abstract

One hundred thirty school children from a schistosomiasis endemic area in Sharkia Governorate, were selected on parasitological findings. Seventy persons were negative on the first screen and turned positive after 3 months of the screening (recently infected). Stool examination, ELISA (IgG & IgM), low avid IgG, and circulating antigens were performed for all patients and controls. ELISA detected IgM in all cases. IgG and circulating antigens in 90% of schistosomiasis patients. Low avidity IgG were detected in 85.71% of recent cases. The specificity of ELISA appeared to be >99%. The IgM/IgG ratio was >1 in patients with recent infection. The percentage of fall of O.D. readings of IgG after addition of 6 molar urea was high among cases with recent infection. Low avid lgG appears to be good and valuable in diagnosis of recent schistosomiasis in man.

MeSH terms

  • Animals
  • Antibodies, Helminth / blood*
  • Antibody Affinity
  • Egypt
  • Enzyme-Linked Immunosorbent Assay / methods
  • Feces / parasitology
  • Immunoglobulin G / blood*
  • Immunoglobulin M / blood
  • Parasite Egg Count
  • Schistosomiasis / diagnosis*
  • Sensitivity and Specificity

Substances

  • Antibodies, Helminth
  • Immunoglobulin G
  • Immunoglobulin M