A comparative study on different diagnostic methods for Helicobacter Pylori

History and Considering the high incidence of gastrointestinal disorders and the involvement of Helicobacter pylori in the occurrence of gastritis, duodenal ulcers and gastric adenocarcinoma and the absence of a generally-accepted and standard method for its diagnosis, this study was carried out to compare the invasive and non-invasive methods on referrals of Shaheed Beheshti hospital in Kashan in 2000. The clinical trial and diagnostic strategy of this study was performed on 127 cases with variant symptoms of gastric disorder and with endoscopic indication. During gastroscopy, samples were collected from antrum for culture, pathological diagnosis and fast urease and 5ml of blood was obtained for evaluation of IgG against, bacterium. The golden standard in this study was on the basis of a positive result for culture, pathological evaluation and fast urease. Then, the sensitivity, specificity, PPV and NPV were determined for criteria of culture, fast urease, histology and ELIZA. The study was performed on 127 cases with an age of 46.3±18 years and 57.5% out of them were male and the remainder (42.5%) were female. The results showed that each test individually or two of the three tests (Histology, fast urease and ELIZA) can not have an appropriate diagnostic value. In this respect, a combination of urease with PPV and/or with NPV can have the greater diagnostic value of 59.3% and 92.3% respectively. Meanwhile, combination of culture and PPV and/or NPV showed the least diagnostic value, i.e. 56.7% and 50% respectively and combination of histology and PPV and/or NPV showed the highest value, i.e. 90% and 100% respectively. Furthermore, ELIZA test in comparison with golden standard had the least sensitivity, even in the presence of histologic evaluation and fast urease. It can be concluded that a combination of fast urease and histology is of high value in diagnosis of Helicobacter pylori in Iran. In addition, the serologic ELIZA test recommended not to be performed because of its low specificity. However, its negative results might be helpful in some cases.