Contact urticaria, eczema and dermatitis to chapatti flour
Chapatti flour is a whole-wheat flour, sometimes blended with malted barley, and is used frequently in Asian cookery. Chapattis are made by combining flour with water and then cooking them on a flat heavy hot plate.
Davies and Orton highlighted three cases of contact reactions to chapatti flour.
One woman had a history of developing itchy weals on her hands immediately after handling chapatti flour. Prick testing to her chapatti flour as well as wheat flour and a scratch patch test to chapatti flour all produced positive weal and flare reactions.
A 36 year-old woman had a ten year history of hand eczema as well as sneezing within minutes of exposure to chapatti flour. Patch testing to her flour was negative, but scratch patch testing to chapatti flour and prick testing to wheat were both positive.
Another had a three year history of persistent hand eczema, affecting the palms of both hands and the fingertips. She experienced itching and burning of her hands immediately after handling chapatti flour. Skin prick tests to chapatti and wheat flour were both positive.
These are all examples of contact reactions to the flour with none of the women reporting any symptoms after eating cooked chapatti.
Davies E, Orton D.
Contact urticaria and protein contact dermatitis to chapatti flour.
Contact Dermatitis 2009 Feb;60(2):113-114