Ceren ERDOĞDU, Zeynep SARIBAŞ, Yakut Akyön YILMAZ

Detection of cagA and vacA genotypes of Helicobacter pylori isolates from a university hospital in Ankara region, Turkey

The cagA and vacA profiles and their association with clinical findings show a distinct geographical distribution. In the present study, we aimed to determine the cagA status and vacA allelic subtypes in strains isolated from a university hospital in Ankara and to evaluate their associations with histopathological and endoscopic findings. Materials and methods: A total of 120 H. pylori strains from stock cultures positive for the ureA gene were randomly included in the present study. Of these strains, cagA and vacA allelic subtypes (s1a, s1b, s2, m1, m2) were examined by polymerase chain reaction. Results: Of the 120 strains, 64 (53.3%) were cagA-positive. However, no significant relationship was found between clinical outcomes and cagA positivity. There were 38 (33.6%) strains that had vacA m1 and 74 (65.5%) that had vacA m2 region. Overall, 75 (70.1%) samples were classified as vacA s1a, 3 (2.8%) as vacA s1b, and 29 (27.1%) as vacA s2. There was no significant relationship between vacA genotypes and endoscopic findings. The predominant vacA genotypes were s1am2 (35.6%) and s1am1 (33.6%), with almost the same rates. Furthermore, cagA positivity was found to be significantly related with the vacA s1am1 genotype. Conclusion: The cagA and vacA profiles of our study population are consistent with the Middle Eastern profile.

Anahtar Kelimeler:

Key words: Helicobacter pylori, cagA, vacA

Detection of cagA and vacA genotypes of Helicobacter pylori isolates from a university hospital in Ankara region, Turkey

Keywords:

Key words: Helicobacter pylori, cagA, vacA,

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Interestingly, this is in agreement with the majority of other reports from Turkey, in which cagA prevalence rates were also found between 55% and 69% (17,19). Moreover, although the majority of the isolated H. pylori strains are cagA-positive in Asian countries, associations of cagA status and disease outcome are not encountered in this region (35). This association was also not demonstrated in studies conducted on Iranian populations (36,37). In the present study, we aimed to determine the cagA prevalence, vacA subtypes, and their associations with clinical findings in Turkey. To the best of our knowledge, there are limited reports from this region regarding the cagA and vacA status of Turkey. This study may contribute to the regional findings, since the geographical data in this issue are of significant importance. In conclusion, we determined the cagA prevalence rate as 53.3% and the vacA predominant subtype as s1am However, no association was determined between clinical outcomes and virulence genotypes. A significant association between cagA positivity and vacA s1am1 genotype was found, in accordance with the previous reports in the literature. In the light of the present results, it can be said that the data from Turkey are consistent with the Middle Eastern profile regarding cagA positivity, vacA status, and their associations with clinical outcomes. Further studies with larger sample sizes are needed in order to clarify the cagA and vacA profile of Turkey.