title: Reciprocal impact of host factors and Helicobacter pylori genotypes on gastric diseases.
abstract: OBJECTIVE
  To assess the impact of Helicobacter pylori (H. pylori) genotypes and patient age and sex on the development of gastric diseases.
  
  
  METHODS
  H. pylori-infected patients (n = 233) referred to the endoscopy unit at Tehran University of Medical Sciences (Tehran, Iran) were diagnosed with chronic gastritis (CG), gastric ulcer (GU), or duodenal ulcer (DU). Brucella blood agar was used for biopsy cultures and H. pylori isolation under microaerobic conditions. H. pylori isolates were confirmed with biochemical tests and through amplification of the 16S rRNA gene. DNA was extracted from fresh cultures of the H. pylori isolates and used for amplification of vacA alleles and the cagA gene. Statistical analysis was performed to determine the association between H. pylori genotypes, age (< 40 years vs > 40 years) and sex of the patient, and gastric diseases.
  
  
  RESULTS
  CG was the most prevalent gastric disease (113/233; 48.5%), compared to GU (64/233; 27.5%) and DU (56/233; 24%). More patients were male, and gastric diseases were more frequent in patients > 40 years (P < 0.05). The percentage of CG and GU patients that were male and female did not show a significant difference; however DU was more common in males (P < 0.05). Interestingly, a diagnosis of CG in patients > 40 years was more common in females (18.5%) than males (11.6%) (P = 0.05), whereas a diagnosis of GU or DU in patients > 40 years was more frequent in males (14.6% vs 10.7% and 12.4% vs 4.3%, respectively). Overall, genotyping of the H. pylori isolates revealed that the vacA s1 (82%), vacA m2 (70%), and cagA (+) (72.5%) alleles were more frequent than vacA s2 (18%), vacA m1 (29.2%), and cagA(-) (all P < 0.05). The vacA s1m2cagA (+) genotype was the most prevalent within the three disease groups. vacA s1m2 frequency was 56.2% with a similar occurrence in all diagnoses, while vacA s1m1 appeared more often in DU patients (33.9%). A genotype of vacA s2m2 occurred in 15% of isolates and was more common in CG patients (21.2%); vacA s2m1 was the least common genotype (3%). The vacA s1 allele was found to be a risk factor for DU, vacA s2 for CG, and vacA s1 and vacA s2 for GU (all P < 0.05). The vacA s2m2 genotype was associated with the development of CG and GU compared to DU (P < 0.05). No correlation was found between vacA m or cagA and gastric diseases.
  
  
  CONCLUSIONS
  The outcome of H. pylori infection is the result of interaction between bacterial genotypes and the age and sex of infected individuals.
authors: Sahar Honarmand-Jahromy, Taher Nejad Sattari, Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
authors: Sahar
authors: S
authors: Honarmand-Jahromy
authors: Sahar Honarmand-Jahromy, Taher Nejad Sattari, Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
authors: Farideh
authors: F
authors: Siavoshi
authors: Sahar Honarmand-Jahromy, Taher Nejad Sattari, Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
authors: Reza
authors: R
authors: Malekzadeh
authors: Sahar Honarmand-Jahromy, Taher Nejad Sattari, Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
authors: Taher
authors: T
authors: Nejad Sattari
authors: Sahar Honarmand-Jahromy, Taher Nejad Sattari, Department of Biology, Tehran Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
authors: Saeid
authors: S
authors: Latifi-Navid
mesh_terms: D000328:Adult; D000367:Age Factors; D000942:Antigens, Bacterial / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001706:Biopsy; D002908:Chronic Disease; D004269:DNA, Bacterial / Q000235:genetics*; D004381:Duodenal Ulcer / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005756:Gastritis / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D005838:Genotype; D016481:Helicobacter Infections / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D054884:Host-Pathogen Interactions; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D021521:Ribotyping; D012307:Risk Factors; D012737:Sex Factors; D013276:Stomach Ulcer / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori
keywords: Age; Gastric disease; Gender; Genotype; Helicobacter pylori