Comparison of an [HM -CAPs] ELISA test and the gold standard tests for detecting helicobacter pylori infection

ABSTRACT

Helicobacter pylori [H. pylori] is one of the main causes of gastritis and is highly related to gastric and duodenal cancer. Different methods are i n t roduced for diagnosis of bacterial infections, but serologic tests are more common. In this study, an ELISA [Enzyme linked immunosorbent assay] test was performed using bacterial high molecular cell-associated proteins [HM-CAPs] containing urease. The sensitivity and specificity of this method was then compared with those using histological [Giemsa and/or modified Gram staining] as well as bacterial culture findings, both considered as gold standard tests for diagnosis. HM-CAPs containing bacterialurease, were extracted by NOG [n-octyl-beta-Dglycopyranoside] detergent and purified on sephacryl gel S-300 HR. Besides, biopsy specimens from antral portion of gastric mucosa together with sera of 168 patients [85 male and 83 female], suspected of H. pylori infection, were obtained. The results of culture and/or histological examinations [gold standard tests] were compared with those of serum ELISA test. Sensitivity and specificity of HM-CAPs ELISA test as compared with histological findings and/or bacterial culture were 93.3% and 95.1% respectively. ELISA test using HM-CAPs antigen is highly specific and sensitive. Therefore, it could be used for serological diagnosis of H. pylori infection