title: Iron Deficiency and IL1β Polymorphisms in Helicobacter pylori-infected Children.
abstract: BACKGROUND
  Helicobacter pylori infection has been associated with an imbalance of iron homeostasis. IL-1β has been related with iron absorption disturbances through a variety of mechanisms. The aim of this study was to evaluate the presence of polymorphic variants for IL-1β cluster and gastric IL1β mRNA expression in H. pylori-infected children and their relationship with hypochlorhydria and iron deficiency (ID).
  
  
  METHODS
  Prospective study of 123 symptomatic children. At endoscopy, antral biopsies were taken for urease test, pathology and culture and blood for analysis of ferritin, transferrin, serum iron, and total iron-binding capacity. Polymorphisms in the IL-1β cluster (positions -511, -31, +3954, ILRN) were determined by PCR-RFLP. Gastric mucosal expression of IL-1β mRNA was determined by RT-PCR.
  
  
  RESULTS
  After exclusions, of 105 patients, 33 (31.4%) were H. pylori positive. Nine (8.6%) children were classified as iron deficient (ID). Helicobacter pylori positivity was associated with ID (OR: 5.1; 95% CI: 1.2-21.9) (p = .04). No significant differences were found in allele frequency for IL1β gene cluster polymorphisms between infected and uninfected children. Helicobacter pylori-infected children with ID had significantly increased gastric IL1β mRNA in comparison with infected children without ID. In addition, a significant positive correlation was observed between mucosal IL-1β mRNA and fasting gastric juice pH. Gastric pH values were significantly increased in H. pylori-infected patients with ID compared to uninfected children.
  
  
  CONCLUSIONS
  The established association between H. pylori infection and ID in children may be mediated by increased gastric mucosal IL-1β.
authors.affiliation: Department of Pediatric Gastroenterology and Nutrition, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Carolina A
authors.initials: CA
authors.lastname: Serrano
authors.affiliation: Department of Pediatric Gastroenterology and Nutrition, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Andrea
authors.initials: A
authors.lastname: Villagrán
authors.affiliation: Laboratory of Molecular Microbiology, Celular and Molecular Biology Program, Faculty of Medicine, Universidad de Chile, Santiago, Chile.
authors.forename: Héctor
authors.initials: H
authors.lastname: Toledo
authors.affiliation: Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK.
authors.forename: Jean E
authors.initials: JE
authors.lastname: Crabtree
authors.affiliation: Department of Pediatric Gastroenterology and Nutrition, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Harris
mesh_terms: D000126:Achlorhydria / Q000453:epidemiology; D000293:Adolescent; D001706:Biopsy; D002648:Child; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D020869:Gene Expression Profiling; D016481:Helicobacter Infections / Q000150:complications*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053583:Interleukin-1beta / Q000096:biosynthesis* / Q000235:genetics*; D000090463:Iron Deficiencies; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011446:Prospective Studies; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics
chemical_list: D053583:Interleukin-1beta; D012333:RNA, Messenger
keywords: Helicobacter pylori; Interleukin-1β polymorphisms; children; iron deficiency