Helicobacter pylori in the Arab population compared with the Jewish population in northern Israel is more resistant to treatment. We assume that these results are caused by overexposure combined with unwise use of antibiotics. A correlation was also found between the type of residence and resistance rates to various antibiotics. Further research is needed to determine the resistance mechanism that may explain these results. Due to the high resistance rate and treatment failure, it is appropriate to consider replacing the standard treatment of H. pylori in these populations.

Background: One main challenge in Helicobacter pylori (H. pylori) eradication is its increasing antibiotic resistance. Additionally, resistance rates vary between geographic areas and periods. However, data are limited since susceptibility testing is not routinely performed. Thus, it is valuable to gather data regarding H. pylori's resistance rates in Israel that would aid in better adjustment of treatment.

BACKGROUND In recent years, associations between specific virulence markers of Helicobacter pylori ( H. pylori ) and gastrointestinal disorders have been suggested. AIM To investigate the presence of virulence factors including vacuolating cytotoxin A genotypes ( s1m1 , s1m2 , s2m1 , and s2m2 ), cytotoxin-associated gene A ( Cag A), and urease activity in H. pylori strains isolated from Arab and Jewish populations in northern Israel and to assess associations between these factors and patients’ demographics and clinical outcomes. METHODS Patients ( n = 108) who underwent gastroscopy at the Baruch Padeh Medical Center, Poriya due to symptomatic gastroduodenal pathologies as part of H. pylori diagnosis were enrolled in the study. Gastric biopsy specimens were collected from the antrum of the stomach. Clinical condition was assessed by clinical pathology tests. Bacteria were isolated on modified BD Helicobacter Agar (BD Diagnostics, Sparks, MD, United States). Bacterial DNA was extracted, and PCR was performed to detect Cag A and vacuolating cytotoxin A genes. Urease activity was assessed using a rapid urease test. RESULTS A significant correlation was found between disease severity and patient ethnicity ( P = 0.002). A significant correlation was found between Cag A presence and the s1m1 genotype ( P = 0.02), which is considered the most virulent genotype. Further, a higher level of urease activity was associated with isolates originating from the Jewish population. Moreover, higher urease activity levels were measured among Cag A-/ s1m1 and Cag A-/ s2m2 isolates. CONCLUSION Our study highlights the importance of incorporating molecular methods for detection of virulence markers of H. pylori in order to tailor optimal treatments for each patient. Further investigation should be performed regarding associations between H. pylori virulence factors and ethnicity.