title: Increased gastric IL-1β concentration and iron deficiency parameters in H. pylori infected children.
abstract: Association between H. pylori infection, iron deficiency and iron deficiency anaemia has been described, but the mechanisms involved have not been established. We hypothesized that in H. pylori infected children increased gastric concentrations of IL-1β and/or TNF-α, both potent inhibitors of gastric acid secretion that is essential for iron absorption, are predictors for low blood concentrations of ferritin and haemoglobin, markers of early depletion of iron stores and anaemia, respectively. We evaluated 125 children undergoing endoscopy to clarify the origin of gastrointestinal symptoms. Gastric specimens were obtained for H. pylori status and cytokine evaluation and blood samples for determination of iron deficiency/iron deficiency anaemia parameters and IL1 cluster and TNFA polymorphisms that are associated with increased cytokine secretions. Higher IL-1β and TNF-α gastric concentrations were observed in H. pylori-positive (n = 47) than in -negative (n = 78) children. Multiple linear regression models revealed gastric IL-1β, but not TNF-α, as a significant predictor of low ferritin and haemoglobin concentrations; results were reproduced in young children in whom IL1RN polymorphic genotypes associated with higher gastric IL-1β expression and lower blood ferritin and haemoglobin concentrations. In conclusion, high gastric levels of IL-1β can be the link between H. pylori infection and iron deficiency/iron deficiency anaemia in childhood.
authors: Laboratory of Research in Bacteriology, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. dqueiroz@medicina.ufmg.br
authors: Dulciene Maria Magalhaes
authors: DM
authors: Queiroz
authors: Andreia Maria Camargos
authors: AM
authors: Rocha
authors: Fabricio Freire
authors: FF
authors: Melo
authors: Gifone Aguiar
authors: GA
authors: Rocha
authors: Kádima Nayara
authors: KN
authors: Teixeira
authors: Simone Diniz
authors: SD
authors: Carvalho
authors: Paulo Fernando Souto
authors: PF
authors: Bittencourt
authors: Lucia Porto Fonseca
authors: LP
authors: Castro
authors: Jean E
authors: JE
authors: Crabtree
mesh_terms: D000293:Adolescent; D018798:Anemia, Iron-Deficiency / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D004724:Endoscopy / Q000379:methods; D005260:Female; D005293:Ferritins / Q000235:genetics / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism*; D005838:Genotype; D016481:Helicobacter Infections / Q000097:blood / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000235:genetics / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000097:blood / Q000378:metabolism*; D008297:Male; D011110:Polymorphism, Genetic; D013270:Stomach / Q000382:microbiology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D005293:Ferritins; D007501:Iron