title: Factors associated with Helicobacter pylori infection by a cagA-positive strain in children.
abstract: Although infection with a cagA-positive Helicobacter pylori strain is considered a risk factor for the development of duodenal peptic ulcer in adults, this association has not been demonstrated in children. The presence of cagA was investigated by polymerase chain reaction in H. pylori strains isolated from 27 children with duodenal ulcer and 53 without duodenal ulcer. All patients (100%) with duodenal ulcer and 33 (62.3%) without ulcer were colonized by a cagA-positive strain (P=.00007). A cagA-positive status was also associated with a more marked macroscopic gastritis, with a greater inflammatory infiltrate of both mononuclear and polymorphonuclear cells in the antral and oxyntic gastric mucosae and degenerative and regenerative changes of the gastric mucosa. Increased cagA positivity was also associated with increased age, but no association between cagA-positive status and sex was observed.
authors.affiliation: Laboratory of Research in Bacteriology, Faculdade de Medicina/UFMG, 30130-100, Belo Horizonte, MG, Brazil. dqueiroz@medicina.ufmg.br
authors.forename: D M
authors.initials: DM
authors.lastname: Queiroz
authors.forename: E N
authors.initials: EN
authors.lastname: Mendes
authors.forename: A S
authors.initials: AS
authors.lastname: Carvalho
authors.forename: G A
authors.initials: GA
authors.lastname: Rocha
authors.forename: A M
authors.initials: AM
authors.lastname: Oliveira
authors.forename: T F
authors.initials: TF
authors.lastname: Soares
authors.forename: A
authors.initials: A
authors.lastname: Santos
authors.forename: M M
authors.initials: MM
authors.lastname: Cabral
authors.forename: A M
authors.initials: AM
authors.lastname: Nogueira
mesh_terms: D000293:Adolescent; D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000032:analysis; D004381:Duodenal Ulcer / Q000150:complications / Q000382:microbiology; D005260:Female; D005753:Gastric Mucosa / Q000276:immunology / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D012307:Risk Factors
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C080866:cagA protein, Helicobacter pylori