Genotyping of Helicobacter pylori Virulence Genes cagA and vacA: Regional and National Study

Abstract

Helicobacter pylori (H. pylori) plays a crucial role in the pathogenesis of gastritis, peptic ulcer, and gastric cancer. The presence of pathogenicity islands (PAI) genes contributes to the pathogenesis of many gastrointestinal disorders. Cytotoxin-associated gene A (cagA) and vacuolating cytotoxin gene (vacA) are the most known virulence genes in H. pylori. So, our aim was to study H. pylori virulence genes’ role in gastric disorders pathogenesis. Our study included 150 adult patients who suffered dyspeptic symptoms and were referred to the GIT endoscopy unit. Gastric biopsies were attained for rapid urease test (RUT) and histopathological examination, and multiplex PCR technique for detection of virulence genes was performed. It was found that 100 specimens were (RUT) positive, of which sixty samples (60%) were PCR positive for H. pylori ureC gene. The vacA and cagA genes were identified in 61.6% and 53% of H. pylori strains, respectively. Only 5 cases were vacA-positive and cagA-negative. The most virulent vacA s1 allele existed in 56.6% of cases. Out of the 60 H. pylori strains, 66% had at least one virulence gene and 34% did not show any virulence gene. H. pylori infection showed significant increase with age. H. pylori are prevalent amid dyspeptic patients in our region. The main genotype combinations were vacA+/cagA+ of s1m1 genotype and they were frequently associated with peptic ulcer diseases, gastritis, and gastroesophageal reflux disease.

Clinical Observation of Helicobacter pylori Infection and Risk Factors and Cytotoxin-Associated Protein A in Patients with Coronary Heart Disease

“…e researchers collected medical data related to hospital admission, including the patient's gender, age, occupation, height, weight, BMI index, smoking and cessation history, history of hypertension, diabetes, and family history, as well as a diagnosis of the patient's 'modern', pedigree, biochemical, Hcy, and inflammatory factors [10,11].…”

“…According to the results of 14C breath test, there were 175 cases in HP infection positive group and 62 cases in HP infection negative group, including 114 males and 61 females in HP infection positive group, aged from 36 to 87 years, the average age was (60.85 ± 10.41) years old, the HP negative group had 33 males and 29 females, ranging in age from 36 to 79 years old, with an average of (61.79 ± 9.31) years old. The researchers collected medical data related to hospital admission, including the patient's gender, age, occupation, height, weight, BMI index, smoking and cessation history, history of hypertension, diabetes, and family history, as well as a diagnosis of the patient's ‘modern', pedigree, biochemical, Hcy, and inflammatory factors [ 10 , 11 ].…”

Characteristics of Helicobacter pylori Heteroresistance in Gastric Biopsies and Its Clinical Relevance

“…And the clinical significance of heteroresistance has been the subject of debate; many studies, such as in vitro experiments, mathematical modeling, animal infection models, and clinical studies, have shown that resistant subpopulations can be enriched during antibiotic exposure and might eventually lead to treatment failure (Kao et al, 2014;Band and Weiss, 2019;Zhang et al, 2021). Some studies have proven that virulence factors, such as vacA, babA2, and oipA, are related to an increased risk of peptic ulcer disease in subjects with H. pylori infection (Kishk et al, 2021;Shahini et al, 2021). Do patients infected with heteroresistance genotype strains have different clinical outcomes?…”

Detection of Helicobacter Pylori in Saliva and Oral Swab Versus Biopsy Samples Using Urease Test, Culture, PCR Technique

“…The VacA gene was detected in 48% of biopsy samples in the current investigation. while in recent study done by Kishk et al, (2021) (Kishk et al, 2021) found that the vacA was identified in 61.6% of H. pylori strains.…”