[Contact urticaria in atopic patients. Apropos of 2 cases].

Contact urticaria appears half an hour after application of allergens on skin area of contact. It is favoured by atopy. Two cases are reported. 16-years-old boy had dermatitis of perioral area, hands and more slightly nape of the neck with urticaria due to local application of potato, carrot and apple. Avoiding those allergens cleared urticaria and dermatitis. 45-years-old woman had face and hands dermatitis associated with contact urticaria to potato and banana on those areas. She had cold urticaria as well. A positive passive transfer (Prausnitz-Küstner) was only seen with potato and banana. It is likely that contact urticaria in the atopics is still under-estimated. Scratching may probably lead to dermatitis. Dermatitis of these two patients could be explained by this way.