Detection of antibody in serum and secretion for the diagnosis of Helicobacter pylori infection.

Helicobacter pylori plays a major role in chronic gastritis and peptic ulcer. In addition, it has been shown to be associated with gastric carcinoma. In this study, the authors compared the detection of IgG antibodies specific to H. pylori by enzyme-immunoassay with culture, histology and a CLO test as tools for diagnosis of H. pylori infection. If the criteria that patients will be considered as H. pylori infected only when their samples are positive by culture or CLO test and histology were used, the sensitivity and specificity of detecting IgG in sera were 96.84 and 72.04 per cent respectively. The use of serological test will be useful as a screening test for H. pylori infection without the need of endoscopy. The authors also performed the assay for detecting IgA antibodies in saliva and gastric juice. The sensitivity and specificity of IgA detection in saliva were 26.79 per oent and 75.00 per cent. As for the assay in gastric juice, although the specificity was as high as 91.67 per cent, the sensitivity is very low (22.22%).