Parasitology

Biography

Biography: Babett Oesterreich

Abstract

Human infection by Strongyloides stercoralis can cause dermatological, intestinal and pulmonal symptoms often passing into a chronic disease. Coproscopic diagnosis is often flawed due to low parasitic loads and discontinuous excretion of larvae. Serodiagnosis is a sensitive tool to overcome these limitations though some available assays based on native antigens from S. ratti larvae lack specificity. We tested whether antigens from S. papillosus is a more specific alternative. Purified native antigens from S. papillosus and S. ratti larvae were tested in IgG ELISA. The following serum panels were used: A patient collective with 22 serum samples positive for anti-Strongyloides IgG, a control panel encompassing 84 serum samples from adult blood donors (n=56), pregnant women (n=12) and children (n=16) and a cross reactivity panel with 92 serum samples from patients infected with other parasites. The ELISA applying S. ratti antigens exhibited a sensitivity of 95% at a specificity of 81% with respect to the control group. Furthermore, the ELISA was reactive in 25% of the cross reactivity panel but not with the 10 Ascaris lumbricoides infected patient samples. When using S. papillosus antigens, the ELISA showed a sensitivity of 91% at a specificity of 92%. Within the cross reactivity panel, it revealed positive reactions in 12% of the samples excluding specimens infected with Trichomonas ssp., Trypanosoma ssp., or Ascaris lumbricoides. Thus, native antigens from S. papillosus larvae exhibit more specificity in the serological diagnosis of human strongyloidiasis.