Study of Patch Testing in Allergic Contact Dermatitis in Hands and Feet

Abstract

Contact Dermatitis (CD) is an altered state of skin reactivity induced by exposure to an external agent. According to the mechanism of elicitation, the following types of contact reactions may be distinguished: Allergic Contact Dermatitis (ACD), Irritant Contact Dermatitis (ICD), Phototoxic and Photo Allergic Contact Dermatitis and Immediate Type Contact Reactions or Immune Contact Urticaria. ACD is a delayed-type hypersensitivity reaction that is elicited when the skin comes in contact with a chemical to which an individual has previously been sensitised. Patch testing remains the gold standard for diagnosing ACD. This study focuses on identifying the allergens causing ACD of hands and feet. METHODStudy was conducted in Osmania General Hospital, Hyderabad, over a period of 12 months' duration. Patients suspected to have contact dermatitis were subjected to patch testing. Based on the history, clinical signs and symptoms, a total of 50 patients were shortlisted in 12 months' duration. RESULTOur study showed that the most common allergen showing patch test positivity in both males and females were metals like chromates followed by cosmetics and others. Patients showed significant improvement in their dermatitis after avoidance of the offending agent. CONCLUSIONPatch test is the method of choice and the "gold standard" in the detection of contact allergy and allergic contact dermatitis.