title: Systematic review and meta-analysis of the proportion of Campylobacter cases that develop chronic sequelae.
abstract: BACKGROUND
  Understanding of chronic sequelae development after Campylobacter infection is limited. The objective of the study was to determine via systematic review and meta-analysis the proportion of Campylobacter cases that develop chronic sequelae.
  
  
  METHODS
  A systematic review of English language articles published prior to July 2011 located using Pubmed, Agricola, CabDirect, and Food Safety and Technology Abstracts. Observational studies reporting the number of Campylobacter cases that developed reactive arthritis (ReA), Reiter's syndrome (RS), haemolytic uraemic syndrome (HUS), irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) ,Guillain Barré syndrome (GBS) or Miller Fisher syndrome (MFS) were included. Data extraction through independent extraction of articles by four reviewers (two per article). Random effects meta-analysis was performed and heterogeneity was assessed using the I(2) value. Meta-regression was used to explore the influence of study level variables on heterogeneity.
  
  
  RESULTS
  A total of 31 studies were identified; 20 reported on ReA, 2 reported on RS, 9 reported on IBS, 3 studies reported on IBD, 8 reported on GBS, 1 reported on MFS and 3 reported on HUS. The proportion of Campylobacter cases that developed ReA was 2.86% (95% CI 1.40% - 5.61%, I(2) = 97.7%), irritable bowel syndrome was 4.01% (95% CI 1.41% - 10.88%, I(2) = 99.2%). Guillain Barré syndrome was 0.07% (95% CI 0.03% - 0.15%, I(2) = 72.7%).
  
  
  CONCLUSIONS
  A significant number of Campylobacter cases develop a chronic sequela. However, results should be interpreted with caution due to the high heterogeneity.
authors.affiliation: Centre for Public Health and Zoonoses, University of Guelph, Guelph, Ontario, Canada. jkeithlin@gmail.com.|Department of Population Medicine, Ontario Veterinary College, Guelph, Ontario, Canada. jkeithlin@gmail.com.
authors.forename: Jessica
authors.initials: J
authors.lastname: Keithlin
authors.affiliation: Centre for Public Health and Zoonoses, University of Guelph, Guelph, Ontario, Canada. sargeanj@uoguelph.ca.|Department of Population Medicine, Ontario Veterinary College, Guelph, Ontario, Canada. sargeanj@uoguelph.ca.
authors.forename: Jan
authors.initials: J
authors.lastname: Sargeant
authors.affiliation: Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada. Kate.Thomas@phac-aspc.gc.ca.
authors.forename: M Kate
authors.initials: MK
authors.lastname: Thomas
authors.affiliation: Laboratory for Foodborne Zoonoses, Public Health Agency of Canada, Guelph, Ontario, Canada. aamir.fazil@phac-aspc.gc.ca.
authors.forename: Aamir
authors.initials: A
authors.lastname: Fazil
mesh_terms: D016918:Arthritis, Reactive / Q000150:complications; D002169:Campylobacter Infections / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D020275:Guillain-Barre Syndrome / Q000150:complications; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications; D019846:Miller Fisher Syndrome / Q000150:complications; D000091402:Prohibitins; D012720:Severity of Illness Index