title: Reactive arthritis in a population exposed to an extensive waterborne gastroenteritis outbreak after sewage contamination in Pirkanmaa, Finland.
abstract: To assess the occurrence, clinical picture, and triggering infections of reactive arthritis (ReA) associated with a large waterborne gastroenteritis outbreak.
  
  
  
  After an extensive sewage contamination of the water supply system, an estimated 8453 of the 30 016 inhabitants of the town of Nokia fell ill. General practitioners and occupational physicians were advised to refer any patients with suspicion of new ReA to rheumatological examination including faecal culture, human leucocyte antigen (HLA)-B27 and antibody tests for Campylobacter, Salmonella, and Yersinia.
  
  
  
  Forty-five patients (33 females, 12 males) aged 16-77 years (median 53) were referred. ReA was diagnosed in 21, postinfectious arthralgia in 13, and other musculoskeletal conditions in 11 patients. HLA-B27 was positive in five out of 44 patients (11%). Of the 21 patients with ReA, possible triggering infections were observed in seven (33%), Campylobacter in four, Yersinia in three, and Salmonella in one, who also had Campylobacter infection. ReA was mild in all but one patient who presented with persistent Salmonella enterica serotype enteritidis infection.
  
  
  
  Taking into account the large population contaminated with potentially arthritogenic agents, the occurrence of ReA was rare and mild in character.
authors.affiliation: Centre for Rheumatic Diseases, Tampere University Hospital, Tampere, Finland. uotila@pshp.fi
authors.forename: T
authors.initials: T
authors.lastname: Uotila
authors.forename: J
authors.initials: J
authors.lastname: Antonen
authors.forename: J
authors.initials: J
authors.lastname: Laine
authors.forename: E
authors.initials: E
authors.lastname: Kujansuu
authors.forename: A-M
authors.initials: AM
authors.lastname: Haapala
authors.forename: J
authors.initials: J
authors.lastname: Lumio
authors.forename: R
authors.initials: R
authors.lastname: Vuento
authors.forename: H
authors.initials: H
authors.lastname: Oksa
authors.forename: J
authors.initials: J
authors.lastname: Herrala
authors.forename: M
authors.initials: M
authors.lastname: Kuusi
authors.forename: J
authors.initials: J
authors.lastname: Mustonen
authors.forename: M
authors.initials: M
authors.lastname: Korpela
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018771:Arthralgia / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D016918:Arthritis, Reactive / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D002169:Campylobacter Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission; D005260:Female; D005387:Finland / Q000453:epidemiology; D005759:Gastroenteritis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D015796:HLA-B27 Antigen / Q000097:blood; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D000091402:Prohibitins; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission; D012477:Salmonella enteritidis / Q000302:isolation & purification; D012720:Severity of Illness Index; D012722:Sewage / Q000382:microbiology*; D015009:Yersinia Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission; D055815:Young Adult
chemical_list: D015796:HLA-B27 Antigen; C000717331:PHB2 protein, human; D000091402:Prohibitins; D012722:Sewage