Helicobacter pylori genotypes among patients in a university hospital in Egypt: identifying the determinants of disease severity

Abstract

Objective: To detect the various of H. pylori genotypes, determine the most prevalent one, and to identify the determinants of disease severity. Methods: Biopsies from 90 patients were collected, however 69 were exclusively analyzed. Recognition of H. pylori was made by rapid urease test, histopathology and polymerase chain reaction. The latter was used to amplify genes encoding for virulence markers such as CagA, vacAs1 and vacAs2. Results: cagA was identified in 45 isolates (65.2%), vacAs1 in 54 (78.3%, predominantly vacAs1a), vacAs2 in 15 (21.7%), vacAm1 in 37 (53.6%), vacAm2 in 32 (46.4%), vacAi1 in 36 (52.2%), and vacAi2 in 32 (46.4%) of strains. vacAi1 gene was the only independent marker of pathogenicity. cagA/vacAs1(a)i1m1 was the most prevalent genotype. Conclusion: isolates possess vacAs1(a) as the predominant allelic variant of vacAs types, with a closely equal distributions of m1 and m2 alleles and of i1 and i2 alleles. The majority of the strains from the population studied are of the cagA/vacAs1(a)i1m1 genotype. vacAi1 is the only determinant of disease severity.

Keywords

• H. pylori, vacAs, vacAi, cagA, gastroduodenal disease

Helicobacter pylori genotypes among patients in a university hospital in Egypt: identifying the determinants of disease severity

Öz

Amaç: Çeşitli H. pylori genotiplerini saptamak, en yaygın olanı belirlemek ve hastalığın ciddiyetini gösteren belirteçleri saptamakYöntem: Doksan hastadan alınan biyopsiler toplandı ancak bunlardan sadece 69’u analiz edildi. H. pylori tanınması hızlı üreaz testi, histopatoloji ve polimeraz zincir reaksiyonu ile yapıldı. Bu sonuncu aynı zamanda CagA, vacAs1 ve vacAs2 gibi virülans belirteçlerini kodlayan genleri amplifiye etmek için kullanıldı.Bulgular: cagA 45 suşta (% 65,2), vacAs1 54 suşta (% 78,3, ağırlıklı olarak vacAs1a), vacAs2 15 suşta (% 21,7), vacAm1 37 suşta (% 53,6) olarak, vacAm2 32 suşta (% 46,4), vacAi1 36 suşta (% 52,2) ve vacAi2 32 (% 46,4) tespit edildi. vacAi1 geni patojenite ile ilgili tek markerdı. cagA/vacAs1 (a) i1m1 geni en yaygın genotip idi.Sonuç: m1 ve m2 alelleri ve i1 ve i2 alellerinin çok yakın eşit dağılımları ile vacAs tipleri içinde vacAs1(a) genine sahip olan izolatlar en baskın alelik varyant idi. Çalışılan suşların büyük çoğunluğu cagA/vacAs1(a)i1m1 genotipinde idi. Hastalığın ciddiyetini gösteren tek tek belirteç vacAi1 idi

Anahtar Kelimeler

• H. pylori, vacAs, vacAi, cagA, gastroduodenal hastalık

Kaynakça

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