Clinical and biochemical aspects of "aspirin-sensitivity"

Progressively increasing doses of aspirin (acetylsalicylic acid--ASA) were tolerated by 14 out of 15 patients with confirmed aspirin-sensitive urticaria and in 7 out of 9 patients with aspirin-sensitive asthma. Blood levels of histamine and prostaglandin (PG) F2 alpha were significantly raised in these patients before ASA administration. PGF2 alpha levels fell to within the normal range after challenge doses of ASA which were sufficient to cause symptoms. Skin prick testing with histamine and codeine phosphate did not show evidence of abnormal tissue reactivity or mast cell reactivity. A wider spectrum of mediators will need to be considered if the mechanism of symptom production is to be understood.