[Immunoenzymatic assay for serodiagnosis of Helicobacter pylori infections]

Enzyme-linked immunosorbent assays (ELISA) have been developed to diagnose H. pylori infection. However, the methods are not standardized. We therefore evaluated the sensitivity of ELISA developed in our laboratory in a study population comprising 38 patients with dyspeptic symptoms and 41 healthy children under 10 years. The assays for immunoglobulin G used a pool of sonicated isolates of H. pylori from five patients with dyspeptic symptoms. Serum levels IgG antibodies to cell sonicates of H. pylori were significantly higher (p < 0.001) in patients with positive culture than in the control group. Cutoff score of 0.231 for positive results was determined with mean + 3ds of the healthy group analyzed. On the basis of this survey, we conclude that a serum dilution of 1:300 and 5 micrograms/ml of antigen, are the optimal condition for rapid screening with high sensitivity of 92% of symptomatic patients for the presence of H. pylori.