title: Helicobacter pylori immunization and atopic dermatitis in South Italian children.
abstract: BACKGROUND
  The epidemiological decrease of Helicobacter pylori (Hp) infection has been recently associated to the increase of several extra-intestinal allergic disorders.
  
  
  OBJECTIVE
  We investigated the role of specific Hp IgG production in the development of IgE or not IgE mediated food allergy (FA) in children affected by atopic dermatitis (AD).
  
  
  METHODS
  From January 2010 to July 2013, 290 South Italian children, aged between 26 and 142 months, were consecutively referred to the Pediatric Clinic of the Pediatric Department at Second University of Naples and were diagnosed as affected by AD. The patients were classified in two groups on the basis of diagnosis of food allergy (88 FA affected and 202 not FA affected) and further divided on the basis of the diagnosis of atopy (63 IgE mediated and 23 not IgE mediated). Hp serum IgG was detected using an enzyme linked immunosorbent assay (ELISA) kit (Wampole® Helicobactor pylori IgG ELISA II, Wampole Laboratories, Cranbury, NJ) and Hp stool antigens using enzyme immunoassay (Premier Platinum HpSa plus, Cincinnati OH).
  
  
  RESULTS
  We found a statistically significant higher prevalence of Hp serology positivity in not FA vs. FA AD-affected children (p = 0.032) and a significant inverse association between FA and Hp immunization (1/OR 0.32 95% CI 0.11-0.95). Further, we identified an absolute prevalence Hp serology positivity in not-IgE-mediated rather than in IgE-mediated FA AD-affected patients (p = 0.0006).
  
  
  CONCLUSIONS
  We hypothesize that specific Hp IgG production could protect against the development of both FA and atopy in AD-affected children.
authors.affiliation: Department of Pediatrics "Francesco Fede" - Second University of Naples, Naples, Italy.
authors.forename: Marcella
authors.initials: M
authors.lastname: Pedullà
authors.affiliation: Department of Pediatrics "Francesco Fede" - Second University of Naples, Naples, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Fierro
authors.affiliation: Department of Pediatrics "Francesco Fede" - Second University of Naples, Naples, Italy.
authors.forename: Ester
authors.initials: E
authors.lastname: Del Tufo
authors.affiliation: Department of Public Health - University of Naples Federico II, Naples, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Alfano
authors.affiliation: Department of Public Health - University of Naples Federico II, Naples, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Triassi
authors.affiliation: Department of Pediatrics "Francesco Fede" - Second University of Naples, Naples, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Perrone
keywords: Atopic dermatitis; Helicobacter pylori; atopy; children; food allergy
references.citation: Helicobacter. 2009 Sep;14 Suppl 1:58-68
references.pmid: 19712170
references.citation: Arch Intern Med. 2007 Apr 23;167(8):821-7
references.pmid: 17452546
references.citation: Allerg Immunol (Paris). 1999 Jun;31(6):201-10
references.pmid: 10443301
references.citation: J Clin Invest. 2006 Apr;116(4):1092-101
references.pmid: 16543949
references.citation: Helicobacter. 2001 Mar;6(1):60-5
references.pmid: 11328367
references.citation: PLoS One. 2008;3(12):e4060
references.pmid: 19112508
references.citation: Blood. 2004 Feb 1;103(3):890-6
references.pmid: 12920031
references.citation: J Am Acad Dermatol. 2000 Nov;43(5 Pt 1):884
references.pmid: 11050606
references.citation: Scand J Gastroenterol. 1998 Nov;33(11):1135-9
references.pmid: 9867089
references.citation: Skinmed. 2006 Jul-Aug;5(4):172-6
references.pmid: 16855407
references.citation: Joint Bone Spine. 2005 Mar;72(2):135-41
references.pmid: 15797493
references.citation: Pediatr Allergy Immunol. 2000 May;11(2):101-5
references.pmid: 10893012
references.citation: Jpn J Infect Dis. 2009 Mar;62(2):120-4
references.pmid: 19305051
references.citation: Pediatr Infect Dis J. 2009 Feb;28(2):157-9
references.pmid: 19106773
references.citation: Dig Dis Sci. 2005 Feb;50(2):381-4
references.pmid: 15745104
references.citation: J Asthma Allergy. 2010 Sep 29;3:139-47
references.pmid: 21437048
references.citation: J Oral Pathol Med. 2004 Mar;33(3):129-32
references.pmid: 15128053
references.citation: J Am Acad Dermatol. 2002 Jan;46(1):141
references.pmid: 11756964
references.citation: J Allergy Clin Immunol. 2002 Jun;109(6):1027-33
references.pmid: 12063536
references.citation: J Pediatr Gastroenterol Nutr. 2011 Aug;53(2):230-43
references.pmid: 21558964
references.citation: Helicobacter. 2007 Oct;12(5):567-71
references.pmid: 17760727
references.citation: Dig Dis Sci. 1999 Feb;44(2):229-36
references.pmid: 10063905
references.citation: J Infect Dis. 2008 Aug 15;198(4):553-60
references.pmid: 18598192