title: The association of intestinal parasitosis and H. pylori infection in children and adults from a Mexican community with high prevalence of parasitosis.
abstract: BACKGROUND
  Experimental evidences have suggested that a Th1 response is unable to eliminate H. pylori colonization; whereas a Th2 response, like the one induced by vaccination, reduces H. pylori infection in animal models. Some parasitic infections induce a polarized Th2 response, which theoretically would favor a reduced H. pylori prevalence. The aim of this work was to study the possible association between parasitic infections and H. pylori prevalence.
  
  
  METHODS
  The study population included 120 children and 188 adults from a low socioeconomic level village. H. pylori prevalence was determined in serum by ELISA; parasitic infections were identified in feces by microscopic examination; and total serum IgE levels, as an indirect indicator of some parasitic infections, were determined by ELISA.
  
  
  RESULTS
  In children, H. pylori prevalence was no different between those with and without intestinal parasitic infection. By contrast, adults with intestinal parasitic infection had a significantly lower H. pylori prevalence than adults without parasites (62.6% compared with 80.4%; p = 0.006, OR 2.45). Also in adults, but not in children, total IgE levels were significantly higher in those without H. pylori infection than in those with H. pylori infection (p < 0.001).
  
  
  CONCLUSIONS
  Intestinal parasitic infections and serum IgE levels showed an age-dependent association with H. pylori prevalence. In adults, but not in children, intestinal parasitic infections and increased IgE levels where associated with a reduced H. pylori prevalence.
authors.affiliation: Unidad de Investigación en Enfermedades Infecciosas, IMSS, México.
authors.forename: Javier
authors.initials: J
authors.lastname: Torres
authors.forename: G Perez
authors.initials: GP
authors.lastname: Perez
authors.forename: C
authors.initials: C
authors.lastname: Ximenez
authors.forename: L
authors.initials: L
authors.lastname: Muñoz
authors.forename: M
authors.initials: M
authors.lastname: Camorlinga-Ponce
authors.forename: F
authors.initials: F
authors.lastname: Ramos
authors.forename: A
authors.initials: A
authors.lastname: Gomez
authors.forename: O
authors.initials: O
authors.lastname: Muñoz
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000276:immunology; D016480:Helicobacter pylori; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007411:Intestinal Diseases, Parasitic / Q000453:epidemiology* / Q000276:immunology; D008800:Mexico / Q000453:epidemiology; D015995:Prevalence
chemical_list: D007073:Immunoglobulin E