title: Anisakis simplex hypersensitivity is associated with chronic urticaria in endemic areas.
abstract: BACKGROUND
  Chronic urticaria (CU) may affect up to 1% of the general population. Anisakis simplex hypersensitivity is frequent in areas where raw fish is consumed and A. simplex allergy represents a relevant cause of acute urticaria. We assessed the possible association between CU and A. simplex sensitization in an area where marinated fish is very frequently eaten.
  
  
  METHODS
  A thorough history of CU was sought in 919 adults seen at the Allergy Center, Bari. CU patients and 187 controls underwent skin-prick testing with a commercial extract of A. simplex, and reactors were recommended a 6-month raw-fish-free diet regimen. Responders were followed after a further 3 months.
  
  
  RESULTS
  Of 919 subjects, 213 (23%) met the criteria for CU and 106/213 (49.7%) were sensitized to A. simplex with a significant difference between patients aged >65 or <65 years (56 vs. 41%, respectively; p < 0.05). All patients hypersensitive to A. simplex were regular consumers of marinated fish. In a control population without CU, the prevalence of A. simplex sensitization was 16% (p < 0.001). The 6-month diet regimen led to the disappearance of urticaria in 82/106 cases (77%) versus 1/42 (2%) subjects who did not change their dietary habits (p < 0.001). All nonresponders were sensitized to house-dust mites. Of 75 responders who were followed-up after 3 months, CU relapsed in 88% of those who had reintroduced raw fish versus 14% of those who were still on the diet (p < 0.001).
  
  
  CONCLUSIONS
  In areas where raw or marinated fish is frequently eaten, A. simplex hypersensitivity is a frequent cause of CU.
authors.affiliation: Department of Internal Medicine, Immunology and Infectious Diseases (MIDIM), University of Bari Medical School, Policlinico, Bari, Italy. mt.ventura@allergy.uniba.it
authors.forename: M T
authors.initials: MT
authors.lastname: Ventura
authors.forename: S
authors.initials: S
authors.lastname: Napolitano
authors.forename: R
authors.initials: R
authors.lastname: Menga
authors.forename: R
authors.initials: R
authors.lastname: Cecere
authors.forename: R
authors.initials: R
authors.lastname: Asero
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D017163:Anisakis / Q000276:immunology*; D000947:Antigens, Helminth / Q000009:adverse effects / Q000276:immunology*; D002908:Chronic Disease; D019353:Endemic Diseases / Q000517:prevention & control / Q000706:statistics & numerical data*; D005260:Female; D005396:Fish Products / Q000009:adverse effects; D005500:Follow-Up Studies; D005512:Food Hypersensitivity / Q000178:diet therapy / Q000453:epidemiology*; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012882:Skin Tests; D014581:Urticaria / Q000178:diet therapy / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D000947:Antigens, Helminth