title: The African enigma: low prevalence of gastric atrophy, high prevalence of chronic inflammation in West African adults and children.
abstract: BACKGROUND
  Helicobacter pylori infection is very common in Africa, yet peptic ulcer disease and gastric malignancy are rare.
  
  
  OBJECTIVE
  The aim of this study was to quantify mucosal responses to H. pylori in Gambian adults and children and to estimate the prevalence of antibodies to bacterial virulence factors (cagA and vacA) in a symptomatic population.
  
  
  METHODS
  Adults (mean 36 SD 12 years) with dyspepsia and children (mean 1.4 years SD 0.4 years) with malnutrition underwent gastroscopy with biopsy. Blood was simultaneously drawn for cagA and vacA antibody status. Histopathological scoring used the modified Sydney classification.
  
  
  RESULTS
  Both adults (n = 45) and children (n = 37) mainly demonstrated chronic mild antral inflammation. Only 2/83 cases of focal atrophy (GA) and 4/83 cases of intestinal metaplasia (IM) were observed. Adults tended to demonstrate more frequent acute (AI) and chronic inflammation (CI) (38% compared with 18% and 85% compared with 72%, respectively). Sixty-seven percent of children were cagA IgG+ and 21% vacA IgG+ and 93% of adults were IgG cagA+ and 86% vacA+. There were no differences in mucosal responses between those who were cagA or vacA positive compared with those who were negative.
  
  
  CONCLUSIONS
  Gambian adults and children mount a CI response to H. pylori but GA, IM and AI are uncommon. cagA and vacA are commonly expressed in Gambian strains of H. pylori. Further studies are needed in order to confirm that GA and IM are not late findings in old age.
authors.affiliation: Department of Paediatrics, Royal Victoria Infirmary, Newcastle, UK.
authors.forename: D I
authors.initials: DI
authors.lastname: Campbell
authors.forename: B F
authors.initials: BF
authors.lastname: Warren
authors.forename: J E
authors.initials: JE
authors.lastname: Thomas
authors.forename: N
authors.initials: N
authors.lastname: Figura
authors.forename: J L
authors.initials: JL
authors.lastname: Telford
authors.forename: P B
authors.initials: PB
authors.lastname: Sullivan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial; D001284:Atrophy; D001426:Bacterial Proteins / Q000276:immunology; D002675:Child, Preschool; D002908:Chronic Disease; D004382:Duodenitis / Q000453:epidemiology*; D005260:Female; D005714:Gambia / Q000453:epidemiology; D005756:Gastritis / Q000453:epidemiology*; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology*; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013270:Stomach / Q000473:pathology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori