title: Association of CagA-positive and CagA-negative Helicobacter pylori strains with patients' symptoms and gastritis in primary care patients with functional upper abdominal complaints.
abstract: BACKGROUND
  CagA-positive Helicobacter pylori strains have been reported to be associated with peptic ulcer or malignancy more often than cagA-negative strains. Less is known about the relation of H. pylori serology (CagA-negative or CagA-positive) to histologic changes in the stomach of patients with functional upper abdominal complaints. The association of H. pylori status with patient symptoms or with different subgroups of non-organic dyspepsia is also obscure. In the present study patients' symptoms and their relation to H. pylori serology (H. pylori-negative, H. pylori-positive but CagA-negative, and H. pylori-positive and CagA-positive) were evaluated in general practice patients who had functional upper abdominal complaints. The association of H. pylori serology with different symptom-based subgroups of functional upper abdominal complaints was also assessed. The severity and activity of inflammation and the presence of atrophy and intestinal metaplasia in the antrum and body were evaluated and compared with H. pylori status.
  
  
  METHODS
  Four hundred consecutive unselected dyspeptic patients in primary care were investigated by means of gastroscopy, upper abdominal ultrasound, laboratory screening including H. pylori and CagA serology, and other examinations if needed. Of these patients 193 with functional upper abdominal complaints were enrolled in this study.
  
  
  RESULTS
  Of the study patients 87 (45%) were H. pylori-negative, 70 (36%) were H. pylori- and CagA-positive, and 36 (19%) were H. pylori-positive but CagA-negative. There were no differences in the occurrence of any dyspeptic symptoms between H. pylori-related subgroups. Nor was there an association between H. pylori status and symptom-based subgroups in our study patients. Inflammation of the stomach was related to H. pylori infection, but CagA-seropositive patients did not have moderate or severe inflammation more often than CagA-seronegative ones. CagA-seropositive patients with functional upper abdominal complaints did not have atrophic changes or intestinal metaplasia in the stomach more often than those who were CagA-negative.
  
  
  CONCLUSIONS
  H. pylori or more specific CagA serology is not associated with any specific symptom profile of dyspepsia or with any symptom-based subgroups in patients with functional upper abdominal complaints in primary care. The study patients with CagA seropositivity did not have more severe histologic changes in the stomach than the patients who were H. pylori-seropositive but CagA-seronegative.
authors.affiliation: Dept. of Medicine, Kuopio University Hospital, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Heikkinen
authors.forename: K
authors.initials: K
authors.lastname: Mayo
authors.forename: F
authors.initials: F
authors.lastname: Mégraud
authors.forename: M
authors.initials: M
authors.lastname: Vornanen
authors.forename: S
authors.initials: S
authors.lastname: Marin
authors.forename: P
authors.initials: P
authors.lastname: Pikkarainen
authors.forename: R
authors.initials: R
authors.lastname: Julkunen
mesh_terms: D015746:Abdominal Pain / Q000209:etiology* / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000378:metabolism*; D001284:Atrophy; D001426:Bacterial Proteins / Q000378:metabolism*; D004415:Dyspepsia / Q000209:etiology; D005260:Female; D005756:Gastritis / Q000209:etiology* / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications* / Q000175:diagnosis* / Q000473:pathology; D016480:Helicobacter pylori / Q000276:immunology* / Q000302:isolation & purification*; D006801:Humans; D007249:Inflammation; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori