title: Increased prevalence of Listeria monocytogenes in the faeces of patients receiving long-term H2-antagonists.
abstract: BACKGROUND
  Human listeriosis is an uncommon infection caused by the Gram-positive organism Listeria monocytogenes.
  
  
  OBJECTIVE
  To investigate the effects of therapeutic gastric acid suppression on faecal isolation of L. monocytogenes and the incidence of human listeriosis.
  
  
  METHODS
  Five stool specimens from each of 20 patients on continuous H2-antagonist therapy and two faecal samples from each of 47 healthy controls were investigated for the presence of Listeria spp.
  
  
  RESULTS
  A higher faecal isolation rate of L. monocytogenes was detected amongst the patients (20%) compared with the controls (2.1%) (P < 0.025). All subjects with stools positive for Listeria spp. were female, this sex difference being significant in the patient group (P < 0.0036) compared with controls. No patient, however, developed listeriosis.
  
  
  CONCLUSIONS
  Patients on long-term gastric acid suppressive therapy may be at increased risk of faecal carriage of L. monocytogenes.
authors.affiliation: Department of Gastroenterology, John Radcliffe Hospital, Oxford, UK.
authors.forename: C A
authors.initials: CA
authors.lastname: Cobb
authors.forename: G D
authors.initials: GD
authors.lastname: Curtis
authors.forename: D S
authors.initials: DS
authors.lastname: Bansi
authors.forename: E
authors.initials: E
authors.lastname: Slade
authors.forename: W
authors.initials: W
authors.lastname: Mehal
authors.forename: R G
authors.initials: RG
authors.lastname: Mitchell
authors.forename: R W
authors.initials: RW
authors.lastname: Chapman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005243:Feces / Q000382:microbiology*; D005260:Female; D005745:Gastric Acidity Determination; D006635:Histamine H2 Antagonists / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D008089:Listeria monocytogenes / Q000302:isolation & purification*; D008088:Listeriosis / Q000139:chemically induced / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D013997:Time Factors
chemical_list: D006635:Histamine H2 Antagonists