Contact urticaria from medical gowns and gloves in a midwife student

We report a case of contact urticaria from medical supplies. A-22-year-old woman, midwife school student, developed pruritic rash on sites in contact with some gowns or gloves during practical trainings. Lesions appeared immediately after wearing gowns or gloves, and disappeared within several minutes. Physical examination revealed wheal on edematous erythema on dorsal aspect of right hand (Fig. 1A). We diagnosed contact urticaria to medical supplies on the basis of morphology and history. The white blood cell count and serum IgE level were 5560/µl and 64 IU/ml, and antigens specific IgE were detected only to banana (0.42 IU/ml, class 1) and not to others including latex.Prick testing was performed with 4 solutions from two gloves and two gowns she used (after cutting 1g of them into 1 cm square pieces, placed in saline for one hour), positive control (histamine chlorohydrate solution,10 mg/mL) and negative control (saline). She had developed rash to 4 items, but not always. Those droplets were wiped off with soft paper tissue, and reading performed after 15 minutes 1 . We noted positive reactions to glove-2 (2.3mm wheal in diameter), gown-1 (2.9mm wheal in diameter) and histamine chlorhydrate solution (3.9mm wheal in diameter), and negative ones to others (Fig. 1B). Cutaneous lesions were prevented by taking 20mg of bilastine, an antihistamine drug． As allergic contact urticaria to medical supplies, cases due to polypropylene were reported 2 3 . Since it was a common component of the gloves and gowns, we speculated that it was the causative agent in our case initially. However, it and other common components were not detected in glove-2 and gown-1 by component analysis and dissolution test. Although dibutyl phosphate were detected in gown-1 and 2, it was unlikely to cause allergic reactions. After these results were obtained, we performed challenge test with glove-1 if it can be used in the future. The patient developed pruritic rash immediately after wearing it despite negative at the prick testing (Fig. 1C). Although we had to be careful for the cause in this case considering the patient's occupation, it was not identified. Therefore, we finally diagnosed our case as non-immunological contact urticaria to medical supplies; lesions were always localized without systemic reactions, and occurred within a few minutes. Although pathology of positive reactions to glove-2 and gown-1 in the prick testing were unclear, we suspect that physical urticaria-like reaction may act in the mechanism of pathology