Contact allergy in Indonesian patients with foot eczema attributed to shoes

BACKGROUND: Shoe dermatitis is a form of contact dermatitis resulting from exposure to shoes. Allergens and types of shoes responsible may vary depending on manufacturing techniques, climatic conditions and indigenous traditions. This study focuses primarily on as yet unexplored shoe dermatitis cases in Indonesia. OBJECTIVE: To determine the prevalence of shoe dermatitis in the Dermatology outpatient clinic, Sardjito University Hospital, Yogyakarta, Indonesia over a period of 3 years and to identify the responsible allergens. METHODS: All patients meeting screening criteria for possible shoe contact dermatitis were patch tested with the European baseline series, shoe series and additional series based on earlier studies of Indonesian leather and shoe manufacturers; some were also patch tested with their own shoe materials and shoe extracts. RESULTS: Sixty-four (7.1%) of 903 patients with foot skin disorders were diagnosed with shoe dermatitis. Twenty-five (52.1%) of 48 patch-tested patients showed positive reactions to one or more allergens related to footwear. Sixteen patients were patch tested with their own shoe materials; 11 showed positive reactions. The most frequent relevant sensitizers were rubber allergens followed by preservatives, shoe adhesives and leather materials. CONCLUSION: Shoe dermatitis is common in Indonesia. Using three series of patch tests, we identified responsible allergens and patterns of sensitization in Indonesian shoe dermatitis patients.