title: Role of Helicobacter pylori infection in pernicious anaemia.
abstract: BACKGROUND
  Pernicious anaemia is associated with atrophic body gastritis and considered an autoimmune disease. Whether Helicobacter pylori is involved in the induction of pernicious anaemia is uncertain.
  
  
  OBJECTIVE
  To investigate the prevalence of Helicobacter pylori infection in pernicious anaemia patients and to ascertain whether the Helicobacter pylori-positive patients had distinctive clinical and gastric morphofunctional characteristics.
  
  
  METHODS
  A series of 81 consecutive pernicious anaemia patients underwent serological, functional and endoscopic/histological investigations.
  
  
  RESULTS
  A total of 49 (60.5%) patients were Helicobacter pylori-positive (males 61.2% vs females 38.8%). No difference was observed in clinical and morphofunctional characteristics between Helicobacter pylori-positive and negative patients, whereas distinctive functional/histological features between histologically Helicobacter pylori-positive (n=8) and serologically Helicobacter pylori-positive (n=41) cases were detected. In the histologically Helicobacter pylori-positive group, Pepsinogen I was higher [13 (058) vs 5 (0-26) ng/ml; p=0.0025)] and positivity for anti-parietal cell antibodies was lower [42.9% vs 76.9, p=0.0867]. Antral histological variables of the gastritis score were significantly higher in the histologically Helicobacter pylori-positive than in the serologically Helicobacter pylori-positive patients, but this latter group had a higher score of body atrophy (2.63+/-0.12 vs 1.71+/-0.29; p=0.0051). Body inflammation was also significantly higher in the histologically Helicobacter pylori-positive group (chronic inflammation: 1.43+/-0.2 vs 1.05+/-0.06; p=0.0271; inflammation acitivity: 0. 57+/-0.3 vs 0.15+/-0.06, p=0.0220). Antral mucosa was normal in 24/41 (58.5%) of the serologically Helicobacter pylori-positive patients, but only in 1/8 (12.5%) of the histologically Helicobacter pylori-positive patients (p=0.0232).
  
  
  CONCLUSIONS
  Almost two thirds of pernicious anaemia patients have evidence of Helicobacter pylori, but only those with an active Helicobacter pylori infection have distinctive functional and histological features. These findings support the hypothesis that Helicobacter pylori infection could play a triggering role in a subgroup of pernicious anaemia patients.
authors.affiliation: Gastroenterology Department, University of Rome La Sapienza, Italy. bruno.annibale@uniroma1.it
authors.forename: B
authors.initials: B
authors.lastname: Annibale
authors.forename: E
authors.initials: E
authors.lastname: Lahner
authors.forename: C
authors.initials: C
authors.lastname: Bordi
authors.forename: G
authors.initials: G
authors.lastname: Martino
authors.forename: P
authors.initials: P
authors.lastname: Caruana
authors.forename: C
authors.initials: C
authors.lastname: Grossi
authors.forename: R
authors.initials: R
authors.lastname: Negrini
authors.forename: G
authors.initials: G
authors.lastname: Delle Fave
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000752:Anemia, Pernicious / Q000175:diagnosis / Q000453:epidemiology*; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis / Q000453:epidemiology*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011336:Probability; D011446:Prospective Studies; D018570:Risk Assessment; D017678:Sex Distribution