Urticaria is multifactorial disease. Type 1 hypersensitivity reaction plays an important role in developing or aggravating the disease, so determining of the causative allergens and avoiding them from patient's environment are helpful in treating the disease. The purpose of this study is to estimate the positive rate of each allergens in urticaria patients and to assess the differences by sex, age, year, residence type and the duration of the disease.

We retrospectively reviewed the medical records of 304 patients with urticaria who underwent skin prick test and 707 patients with urticaria who underwent serum allergen test at the department of dermatology in Mok-Dong Hospital, Ewha Womans University for 10 years from March 1998 to April 2008.

In skin prick test, the positive rates of major allergen were D.farinae 52.0%, D.pteronyssinus 47.7%, cockroach mix 27.3%, weeds 15.8%, shellfish 15.1% in that order. D.farinae, D.pteronyssinus and cockroach mix had the highest positive rates in acute and chronic urticaria, but the rates in acute urticaria were much lower than those in chronic urticaria. In serum allergen test, the positive rates of major allergen were D.farinae 31.8%, D.pteronyssinus 24.5%, housedust 24.0%, acarus siro 11.0%, cat fur 9.3%. D.farinae and D.pteronyssinus showed the highest positive rates in 20s and cockroach mix in 40s.

Some allergens had statistically significant differences of positive rates by each parameter. Therefore identifying and analysing allergen trends would play an important role in deprivation therapy in urticaria patients.