Cold Stimulation Test and Histamine Release in Primary Acquired Cold Urticaria

The patient was a 10-year-old boy who complained of urticaria upon exposure to cold air and after swimming in the pool. He also had seasonal asthma and wheezing after strenuous activities. To determine whether he had primary acquired cold urticaria, we performed a cold stimulation test twice. We likewise wanted to know whether a difference in response with regard to histamine release existed between blood samples taken from the challenged and the unchallenged sites. We obtained blood samples for histamine release initially at the site opposite the challenged forearm, and then on the same side on two separate occasions. We noted the appearance of constitutional signs and symptoms and correlated the time of their appearance with the result of histamine levels. The patient complained of pruritus and wheals appeared at the 5 minute in both tests. Results of plasma histamine release in the two measurements showed the highest releasability at 15 min. Our findings revealed that histamine is released systemically in response to cold stimulation regardless of the site where the blood sample was obtained.