Usefulness Of Immunoglobulin G Avidity Enzyme Linked Immunosorbent Assay (ELISA) As A Confirmatory Test In Serodiagnosis Of Acute Toxoplasma Infection

1Atef H. Hussein and 2Gamal Kenawy

Departments of 1Parasitology and 2Biochemistry, Benha Faculty of Medicine, Zagazig University, Egypt.

Avidity ELISA is an uprising method developed to discriminate between acute and chronic infections. The usefulness of this technique was tested on 143 sera screened for specific antitoxoplasma IgM and IgG antibodies using conventional ELISA. Of the 10 sera found IgM and IgG positive, only one (10%) showed low IgG avidity index (AI) indicative of acute Toxoplasma infection. Out of 63 sera found positive for specific antitoxoplasma IgG only, 60 (95.2%) showed high IgG avidity index, indicative of chronic infection. In conclusion, IgG avidity ELISA might facilitate more accurate diagnosis of acute Toxoplasma infection in pregnant women, particularly in Egypt where Gynecologists depend on a single serum sample in serodiagnosis of acute toxoplasmosis. Based on this additional information, many women will avoid repeated testing, unnecessary examinations, treatment and anxiety.