ABSTRACT
H.pylori is a microaerophilic, garm-negative, spiral organism with 4-6 flagella. The bacterium is an etiologic agent for chronic gastritis and plays a major role in effecting peptic ulcer, gastric cancer, lymphoma, H. pylori infection has a high seroprevalence in iran [> 90%], thus, diagnosis and treatment of H. pylori infection is very important. The presence of H. pylori infection was determined in 100 patients undergoing upper gastrointestinal endoscopy over 9 month period. The presence of H. pylori was detected in gastric mucosal biopsy specimens through Biopsy Urease Test, PCR and histopathology. A medium was used for urease test, Normal Broth Urea. The biopsy is placed in a both containing urea and a PH indicator. The gold standard is histopathology examination. We designed a PCR for amplifying the H. pylori gene encoding ure C [294bp]. The results of urease test were 66.6% sensitivity and 69.7% specefity. The results of PCR assay were 98.6% sensitivity and 93% specifity. There was a significant difference between the specifity and sensitivity of urease test and PCR. The result of this study showed that urease test was not a sensitive and specific method for accurate detection of the infection, level of the sensitivity is too low to be used as the sole method of detection in ordinary practices. In this situation, other tests should be used