Airborne allergic contact dermatitis caused by methylisothiazolinone in a child sensitized from wet wipes

Abstract

A 3-year-old girl with no history of atopic dermatitis was referred from a paediatric department because of recalcitrant perioral dermatitis of duration 10 weeks (Fig. 1); this had initially been treated as impetigo with systemic and topical antibiotics, with little or no effect. Topical hydrocortisone/miconazole had a limited effect. The patient was treated as an inpatient with topical fusidic acid and betamethasone 17-valerate (FucicortTM), which improved the dermatitis. Microbiological and fungal cultures were negative. Patch tests were performed with the European baseline series (TRUE TestTM; SmartPractice, Hillerod, Denmark) supplemented with the remaining baseline allergens in Finn Chambers® on Scanpor® tape (SmartPractice, Phoenix, AZ, USA). The patient was also tested with her own products. The tests showed positive reactions to methylisothiazolinone/methylisothiazolinone (++ on D3; + on D7) and methylisothiazolinone 0.02% aqua (+++ on D3). There was also a positive reaction to FucidinTM cream ‘as is’ (+ on D3), but there were no positive reactions to the FucidinTM ointment and fusidic acid sodium salt 2% pet. (Chemotechnique Diagnostics, Brondby, Denmark), suggesting that a vehicle substance