Background: Helicobacter pylori (H. pylori) is a gram-negative,
micro-aerophilic, curved rod that causes a transmissible bacterial infection of
the gastric mucosal surface and affect about one half of the world?s
population. It induces chronic gastritis in all infected individuals, but only
induces clinical diseases in 10-20% of them. This may be related to differences
in genetic susceptibility of the host, environmental factors, and genetic
diversity of H. pylori. Aim: This study was conducted to identify the frequency
of the genetic virulence factors (cagA, vacA and babA2) of H. pylori and their
possible association with gastroduodenal diseases. Methods: The study was
conducted on 70 adult patients with upper gastrointestinal complaints. All
patients were subjected to full history taking, clinical examination,
gastroduodenoscopy. Four antral biopsies were taken for genotyping by PCR,
histopathological examination and culture. Results: All the patients (100%) had
chronic active H. pylori gastritis by histopathological examination. The most
frequent H. pylori genotype was cagA (67.8%) followed by vacA s1a (61%) and
vacA m2 (61%), while the least frequent was babA2 (18.6%). CagA was associated
with vacA s1a in (83.3%) with statistical significance. Most patients with cagA
positive isolates (77.8%) had no heart burn with statistical significance which
may support the protective role of cagA against GERD. There was no significant
difference between genotypes distribution as regards culture positive and
culture negative H. pylori strains. CagA, vacA s1a and vacA m2 had the highest
prevalence in patients with PUD, gastritis and duodenitis while babA2 had the
least prevalence. Although in patients with PUD and NUD the prevalence of cagA
was (65.1%, 75%) and vacA s1 was (62.8%, 56.3%) respectively, the association
between these H. pylori genotypes and PUD did not reach a level of statistical
significance. Conclusion: None of H. pylori genetic virulence factors
individually can accurately predict clinical outcome and one has to recognize
the importance of the bacteria-host interaction in the final outcome. - Seemore at:
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