title: Atopic manifestations are more common in patients with Crohn disease than in the general population.
abstract: BACKGROUND
  The role of TNF-alpha in Crohn disease is now well established and anti-TNF-alpha is frequently used as a second- or third-line treatment. Tumor necrosis factor-alpha (TNF-alpha) is traditionally associated with macrophages but has recently also been found in mast cells of the ileal wall in patients with Crohn disease. As it is well known that mast cells and TNF-alpha play important roles in atopic manifestations like asthma, allergic rhinitis; and eczema the aim of this study was to investigate whether these are seen more commonly in Crohn patients than in the general population.
  
  
  METHODS
  Patients with Crohn disease (n = 308), aged 18-50 years, living in the Linköping region in southeast Sweden, were asked to answer a questionnaire regarding the presence of any kind of atopic manifestations. The questionnaire was also sent to 930 controls collected from the Southeastern Region Population Registry. The controls were matched according to age, sex, and place of residence.
  
  
  RESULTS
  The response rate among the Crohn patients was 91% (280/308) and among controls 84% (779/930). Eczema was a significantly more frequent manifestation, being almost twice as common in Crohn patients (27%) as in the general population (16%). Adjustment by logistic regression for place of residence, gender, age and coexistence of any other atopic manifestation did not change the odds ratios significantly.
  
  
  CONCLUSIONS
  Atopic manifestations as a group, and eczema as a single manifestation, are significantly more frequent in Crohn patients than in the general population.
authors.affiliation: Dept. of Surgery, Unit of Colorectal Surgery, University Hospital, Linkoping, Sweden. par.myrelid@lio.se
authors.forename: P
authors.initials: P
authors.lastname: Myrelid
authors.forename: M
authors.initials: M
authors.lastname: Dufmats
authors.forename: I
authors.initials: I
authors.lastname: Lilja
authors.forename: C
authors.initials: C
authors.lastname: Grinn
authors.forename: O
authors.initials: O
authors.lastname: Lannerstad
authors.forename: R
authors.initials: R
authors.lastname: Sjödahl
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000150:complications; D003424:Crohn Disease / Q000150:complications* / Q000276:immunology; D004485:Eczema / Q000150:complications; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000150:complications*; D008297:Male; D008875:Middle Aged; D012221:Rhinitis, Allergic, Perennial / Q000150:complications; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications