Evaluation of a contact allergy clinic

Abstract

This study aims to assess the value of patch testing in a specialist contact allergy clinic as compared to testing carried out by general dermatologist for the diagnosis of contact allergy. One hundred consecutive patients referred for patch testing were tested to the European standard and specialized series. A comparison was made between patch tests read and interpreted by a consultant dermatologist with an interest in contact allergic dermatitis and by an experienced registrar who had not yet received any formalized specialized training. Results of testing with additional allergens acquired following the establishment of the specialist clinic were examined. In addition patients with a hand problem and/or symptoms suggestive of contact urticaria underwent skin prick testing. There was a variation in patch test reading and interpretation between the consultant and registrar in 10 patients. Patch testing using allergens from the additional series revealed additional relevant contact allergies in 19 patients. In 14 patients, allergies would have been missed by a limited additional series. Contact urticaria was detected in seven patients. This study has confirmed the value of a specialist contact clinic in the diagnosis of contact allergy. The importance of formalized training in patch test reading and interpretation, testing with additional series and prick testing for the diagnosis of contact urticaria are highlighted.