Occasionally, agents that are applied to the skin produce an immediate wheal-and-flare reaction rather than the usual delayed-type hypersensitivity dermatitis. Open tests that are observed for 30 minutes detect the urticarial reaction, whereas standard closed patch tests that are removed after 48 hours are negative. In this article, we report contact urticaria due to sensitivity to formaldehyde and terpinyl acetate, which are found in a commercial spray starch.
Report of a Case
A 20-year-old woman had a one-year history of pruritus and hives that occurred within minutes of wearing spray-starched clothes. New "wash-and-wear" clothes produced similar symptoms, but washed, unstarched clothes were worn without difficulty. Personal and family histories were negative for atopy. Open tests were applied at different times to her forearm and back with the commercial spray starch and its ingredients (Table). Within 15 minutes, urticaria was observed resulting from the spray starch, formaldehyde, and perfume. Further testing