Patch Test Results of 276 Cases with Footwear Dermatitis - A Retrospective Study from a Tertiary Care Centre in South India

BACKGROUND: Allergic contact dermatitis (ACD) is a major cause for foot wear dermatitis. Patch testing is the standard investigation for diagnosis of ACD. Identification of the causative allergen and avoidance of the same is the most important for patient management. AIMS: This study was conducted to find the common allergens in footwear, causing ACD, by retrospective analysis of the data of patients who had undergone patch testing with footwear series (FWS), approved by the Contact and Occupational Dermatoses Forum of India. MATERIALS AND METHODS: A total of 276 cases with footwear dermatitis who underwent patch test with FWS using Finn chamber method were studied. Statistical analysis was done using statistical package for social sciences (SPSS) version 24. Data was described using frequency and percentages. P value of less than 0.05 was considered significant. RESULTS: In this study 101 (36.5%) patients had positive patch test to at least one allergen. Among this, 43 (15.6%) were positive for single allergen only and 58 (21.01%) patients had positive patch test reactions to multiple allergens. The most common allergens with positive patch test were black rubber mix, mercapto benzo thiazole, and thiuram mix. Patients with either a positive or negative patch test had no statistically significant difference in the history of atopy. The limitations of this study include the lack of patch testing with the patient's own footwears and lack of follow-up after informing patients regarding allergen avoidance. CONCLUSIONS: Patch test must be done for all foot eczema cases for early identification of the causative allergen and also to provide suitable alternatives.