Helicobacter pylori in Dyspepsia: Phenotypic and Genotypic Methods of Diagnosis

Helicobacter pylori affects almost half of the world's population and therefore is one of the most frequent and persistent bacterial infections worldwide. H. pylori is associated with chronic gastritis, ulcer disease (gastric and duodenal), mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Several diagnostic methods exist to detect infection and the option of one method or another depends on various genes, such as availability, advantages and disadvantages of each method, monetary value, and the age of patients.

Patients with complaints of abdominal pain, discomfort, acidity, and loss of appetite were chosen for endoscopy, detailed history was contained, and a physical examination was conducted before endoscopy. Biopsies (antrum + body) were received from each patient and subjected to rapid urease test (RUT), histopathological examination (HPE), polymerase chain reaction (PCR), and culture.

Of the total 223 biopsy specimens obtained from dyspeptic patients, 122 (54.7%) were positive for H. pylori for HPE, 109 (48.9%) by RUT, 65 (29.1%) by culture, and 117 (52.5%) by PCR. The specificity and sensitivity were as follows: RUT (99% and 88.5%), phosphoglucosamine mutase PCR assay (100% and 95.9%), and culture (100% and 53.3%), respectively.

In this study, we compared the various diagnostic methods used to identify H. pylori infection indicating that, in comparison with histology as gold standard for detection of H. pylori infection, culture and PCR showed 100% specificity whereas RUT and PCR showed 99% and 100% sensitivity, respectively.