Estudo de marcadores de virulência do Helicobacter pylori e sua associação com gastrite, úlcera péptica e câncer gástrico no nordeste do Brasil

Abstract

The main gastric diseases are associated with H. pylori infection, a bacterium that demonstrates a high level of genotypic diversity , the expression of various genes that confer greater virulence strains. The objective was to evaluate genetic markers of virulence of H. pylori strains of in patients with gastritis, ulcers and gastric cancer. Genotyping of the strains was performed by PCR. We evaluated 183 patients, attended at Walter Cantídio University Hospital, 88 men , 95 women , ranging in age from 18-88 + 52.8 years , diagnosed positive for infection by H. pylori, 48 with gastric cancer, 71 with peptic ulcer and 64 with gastritis. The prevalence of genotypes was: 75/183 (40.9 %) vacA i1, 29/183 (15.8 %) vacA i2, 146/183 (79.8 %) babA2, 81/183 (44.3 %) oipA, 107/183 (58.5%) iceA1 and 56/183 (30.6%) iceA2. In the group of patients with gastric cancer was observed that the most frequent genotype was babA2 35/48 (72.9 %), followed by the gene iceA1; 31/48 (64.6 % ) and oipA 18/48 (37 , 5%). In the group of patients with peptic ulcer the most frequent genotype was babA2 63/71 (88.7 %), followed by the gene iceA1; 40/71 (56.3 %) and oipA 31/71 (43.7 %). In the group of patients with gastritis the most frequent genotype was babA2 48/64 (75.0%), followed by the gene iceA1 vacA i1 and 36/64 (56.2%) and oipA 32/64 (50.0 %). The i2 vacA allele was associated with gastric cancer. In peptic ulcer the prevalence of all genotypes and was associated with babA2. Gastritis was associated with vacA i1 allele. There were no association between the diseases and the other genotypes. The genetic strains of H. pylori and its association with gastric disorder is important to clearly establish their pathogenic role for the various clinical outcomes related to this infection