Whole cell ELISA for detection of Helicobacter pylori antibodies with reference to peptic ulcers

ABSTRACT

The specific objectives of this study are to compare isolation of the H. pylori from biopsies with results of a whole cell enzyme linked immunosorbent assay [ELISA] for specific antibodies in serum and saliva. One hundred and nine patients attending outpatient endoscopy clinics were randomly selected. Two biopsies were collected from each patient, one biopsy from each site was cultured and an additional biopsy was taken from the antrum for campylobacter like organism [CLO] test. Blood and saliva samples were also collected to determine specific antibodies to H. pylori using whole cell ELISA. H. pylori specific serum IgG, IgM, IgA and salivary IgA in patients were determined by whole cell ELISA. The results confirmed the diagnostic value of ELISA for determination of serum IgG antibodies against H. pylori and showed that 1/100 dilutions of serum and 1 /5 dilutions of saliva distinguished between H. pylori infected and non-infected patients which is correlated with CLO test. The results of the ELISA assay are significantly correlated with the presence of H. pylori in gastric biopsies determined with CLO test, microscopy and culture. In addition, the assay differentiated between patients with and without peptic ulcers. These results suggest that ELISA might be useful for screening patients referred for endoscopy, thereby reducing the endoscopy list in the clinic