Interleukin-8 genetic polymorphism and its relation to Helicobacter pylori infection and Helicobacter pylori-associated gastric diseases.

Helicobacter pylori (H. pylori) infection has a variety of clinical outcomes, and host genetic factors play an important role in this process. Cytokines are important factors in mediating and controlling the inflammatory process during H. pylori infection. Interleukin-8 (IL-8) plays a critical role in the epithelial cell response to H. pylori infection and the development of H. pylori-related gastric disorders. The IL-8 gene has an A/T base pair polymorphism in the promoter region (-251), which has been linked to an increase in interleukin production by gastric epithelial cells. In this context, the goal of our study was to determine the polymorphism in the IL-8 gene and its relation to H. pylori infection and H. pylori-associated gastric diseases. Gastric biopsy specimens were collected from 44 patients with H. pylori infection and 29 patients without H. pylori infection. The rapid urease test and detection of the glmM gene were used to diagnose H. pylori infection. Polymerase chain reaction-restriction fragment length polymorphism was used to identify the polymorphism in the Il-8 gene (at position-251). The presence of the A/A and T/A genotypes of the IL-8 gene was found to be significantly associated with susceptibility to H. pylori infection (p = 0.012 and p = 0.004, respectively). Also, the IL-8 A allele was significantly associated with H. pylori infection in our study (p = 0.002). We did not find a significant association between IL-8 gene polymorphism and a higher risk of gastritis and peptic ulcer disease. In conclusion, IL-8 gene polymorphism at -251 position was significantly associated with H. pylori infection.

Evaluation of Non Invasive versus Invasive Methods for Diagnosis of Helicobacter pylori Infection among Patients with Gastroduodenal Disorders.

H. pylori, a spiral gram-negative bacterium, is associated with gastroduodenal diseases. All H. pylori diagnostic assays have limitations. Cytotoxin-associated gene A (cag A), a virulence marker, can be identified by PCR. We evaluated H. pylori diagnostic methods, invasive: rapid urease test (RUT), and histopathological examination (HE), and serology as non-invasive method. Positive cases were studied for presence of cag A gene. Upper endoscopies and gastric biopsies were performed on 67 dyspeptic patients for RUT, HE and PCR. Anti H. pyloriIgG were measured by ELISA. Of 67 dyspeptic patients, 23 (34%) had more than one endoscopic finding, 46 (68.7%) were H.pylori positive by HE, and 21(31.3%) were negative with variable grades of mucosal antral neutrophil infiltration. Of the 46 HE positives, PCR detected CagA in 22 (47.8%). Using HE as the gold standard test, the sensitivity of ELISA and RUT was 93.48% and 86.96%, respectively; and the specificity was 85.71% and 47.62%, respectively. In conclusion, IgG detection by ELISA is a suitable screening test for diagnosis of H. pylori associated gastroduodenal diseases. Histopathology should be performed in ELISA negative cases to exclude infection.