title: Prevalence and clinical relevance of cagA, vacA, and iceA genotypes of Helicobacter pylori isolated from Slovenian children.
abstract: BACKGROUND
  Although infection with Helicobacter pylori in children mostly induces asymptomatic chronic gastritis, the clinical outcome of H pylori infection is generally unpredictable. To identify the risk subgroup of infected children who can progress toward serious gastrointestinal disease, we assessed the prevalence of H pylori virulence genes cagA, vacA, and iceA in children from southeastern Europe and correlated their presence with the severity of histological changes in the stomach.
  
  
  METHODS
  A total of 165 children (age range 4-18 years, mean 13 years) with H pylori infection were studied for a 6-year period. Virulence genes were determined by polymerase chain reaction from biopsy samples.
  
  
  RESULTS
  The cagA gene was present in 61.2% of patients. The predominant vacA genotype was s1m1 (42%), followed by s1m2 (28%), and s2m2 (24%). IceA genotypes iceA1 and iceA2 were detected in 62% and 31% of the samples, respectively. Multiple genotypes were found in 11.5% of isolates. The H pylori density score, the degree of chronic and acute inflammation, correlated with a cagA-positive status (P < 0.01, P < 0.01, P = 0.01, respectively). Higher bacterial infiltration (P < 0.01) and degree of chronic inflammation (P = 0.03) were detected in vacA s1-positive samples.
  
  
  CONCLUSIONS
  CagA, vacA s1m1, and iceA1 genotypes are the predominant genotypes of H pylori isolated from the southeastern European pediatric population. CagA and vacA s1 are important virulence determinants of H pylori in children, but were not found associated with an increased incidence of precancerous gastric lesions.
authors.affiliation: Department of Gastroenterology, University Medical Center Ljubljana, Slovenia. matjaz.homan@guest.arnes.si
authors.forename: Matjaz
authors.initials: M
authors.lastname: Homan
authors.forename: Bostjan
authors.initials: B
authors.lastname: Luzar
authors.forename: Bostjan J
authors.initials: BJ
authors.lastname: Kocjan
authors.forename: Rok
authors.initials: R
authors.lastname: Orel
authors.forename: Tina
authors.initials: T
authors.lastname: Mocilnik
authors.forename: Maja
authors.initials: M
authors.lastname: Shrestha
authors.forename: Maja
authors.initials: M
authors.lastname: Kveder
authors.forename: Mario
authors.initials: M
authors.lastname: Poljak
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005798:Genes, Bacterial; D005838:Genotype; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D007249:Inflammation / Q000382:microbiology; D008297:Male; D017524:Slovenia; D013270:Stomach / Q000382:microbiology / Q000473:pathology*; D037521:Virulence Factors / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D037521:Virulence Factors