title: Arthritis risk after acute bacterial gastroenteritis.
abstract: OBJECTIVE
  Reactive arthritis (ReA) may occur from bacterial gastroenteritis. We studied the risk of arthritis after an outbreak of Escherichia coli O157:H7 and Campylobacter species within a regional drinking water supply to examine the relationship between the severity of acute diarrhoea and subsequent symptoms of arthritis.
  
  
  METHODS
  Participants with no known history of arthritis before the outbreak participated in a long-term follow-up study. Of the 2299 participants, 788 were asymptomatic during the outbreak, 1034 had moderate symptoms of acute gastroenteritis and 477 had severe symptoms that necessitated medical attention. The outcomes of interest were new arthritis by self-report and a new prescription of medication for arthritis during the follow-up period.
  
  
  RESULTS
  After a mean follow-up of 4.5 yrs after the outbreak, arthritis was reported in 15.7% of participants who had been asymptomatic during the outbreak, and in 17.6 and 21.6% of those who had moderate and severe symptoms of acute gastroenteritis, respectively (P-value for trend = 0.009). Compared with the asymptomatic participants, those with moderate and severe symptoms of gastroenteritis had an adjusted relative risk of arthritis of 1.19 [95% confidence interval (CI) 0.99-1.43] and 1.33 (95% CI 1.07-1.66), respectively. No association was observed between gastroenteritis and the subsequent risk of prescription medication for arthritis (P = 0.49).
  
  
  CONCLUSIONS
  Acute bacterial gastroenteritis necessitating medical attention was associated with a higher risk of arthritic symptoms, but not arthritic medications, up to 4 yrs afterwards. The nature and chronicity of these arthritic symptoms requires further study.
authors.affiliation: London Kidney Research Unit, Division of Nephrology, London Health Sciences Centre, ON, Canada.
authors.forename: A X
authors.initials: AX
authors.lastname: Garg
authors.forename: J E
authors.initials: JE
authors.lastname: Pope
authors.forename: H
authors.initials: H
authors.lastname: Thiessen-Philbrook
authors.forename: W F
authors.initials: WF
authors.lastname: Clark
authors.forename: J
authors.initials: J
authors.lastname: Ouimet
mesh_terms: D016918:Arthritis, Reactive / Q000453:epidemiology* / Q000382:microbiology; D001424:Bacterial Infections / Q000150:complications* / Q000382:microbiology; D016123:Campylobacter jejuni / Q000302:isolation & purification; D004196:Disease Outbreaks; D019453:Escherichia coli O157 / Q000302:isolation & purification; D005500:Follow-Up Studies; D005759:Gastroenteritis / Q000453:epidemiology* / Q000382:microbiology; D006801:Humans; D009864:Ontario / Q000453:epidemiology; D018579:Patient Selection; D000091402:Prohibitins; D012307:Risk Factors; D013997:Time Factors; D014871:Water Microbiology; D014881:Water Supply / Q000592:standards