Airborne contact dermatitis to methylchloroisothia‐zolinone/methylisothiazolinone in a boy

A 13-year-old boy presented with erythematous papules and eczematous plaques on his right arm, neck, upper chest region and face with oedematous swelling of the eyelids. Allergic contact dermatitis was diagnosed and treated with topical glucocorticosteroids. Epicutaneous patch testing was performed with the standard series recommended by the German Contact Dermatitis Research Group (DKG), and DKGseries of preservatives, technical oils andmetals test (1) according to current guidelines (2). Only one positive reaction to methylchloroisothiazolinone= methylisothiazolinone (MCI=MI, 3:1) was seen; questionable reactions occurred to Peru balsam and formaldehyde. The initial case history revealed no indication of a causative allergen in this case. After learning of the positive reaction to MCI=MI, we questioned the boy’s family about recent changes in their living environment. The parents then recalled that they had repainted their kitchen walls 1 day before their son experienced symptoms. The boy had merely entered the room during the painting but had not been otherwise involved. Examination of the household wall paint used (Conti Super-Objektfarbe , Chemische Werke Kluthe GmbH, Heidelberg, Germany) revealed a concentration of 30 p.p.m. of MCI= MIPatch testing for bronopol, also contained in the wall paint, was negative. The paint contained no formaldehyde.