Pars Journal of Medical Sciences

Value of Urease Test in the detection of Helicobacter pylori infections

Authors

Abstract

Introduction: H. pylori is 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.


Material and Methods : The presence of H. pylori infection was determined in 100 patients undergoing upper gastrointestinal endoscopy over 9 month period. The presence of H. pyolri was detcted in gastric mucosal biopsy specimens by Biopsy Urease Test, PCR and histopathology. A media was used for urease test, Normal Broth Urea. The biopsy is placed in a broth containing urea and a PH indicator. The goldstandard is histopathology examination. We designed a PCR for amplifying the H. pylori gene encoding ure C (294 bp).


Results : 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.


Conclusion : The result of This study showed  that urease test was not a sensitive and specific method for accurate detection of  the infection. It a level of the sensitivity is too low to be used as the sole method of detection in ordinary practic. In this situation other/ tests should be used.

Keywords

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