Retrospective Analysis of Patch Test Results Between 2011 and 2013 in Hospital Selayang, Malaysia

ABSTRACT

Introduction:Patch test is the gold standard diagnostic test for contact allergy. Periodic analysis of the trend ofcontact allergy provides a valuable guide to clinicians. We aim to study the pattern of contact allergyin adults at Hospital Selayang.Methods:This is a retrospective review of patch test data in adults suspected with allergic contact dermatitisbetween January 2011 and December 2013 at Hospital Selayang.Results:There were 705 subjects with 247 males (35%) and 458 females (65%). At least 1 positive reactionwas detected in 546 (77.4%) subjects patch tested with European Baseline Series (EBS) and additionalseries. The top 5 common allergens in the EBS were nickel sulfate (28.7%), cobalt chloride (13.6%),paraben mix (11.6%), balsam of peru (10.6%), and potassium dichromate (10.5%). Among thosepatch tested with rubber additives series, the top 3 allergens were N,N-Diphenylguanidine (DPG),N-Cyclohexyl-N-phenyl-4-phenylenediamine (CPPD), and N-Cyclohexylthiophthalimide. Of thetop 5 common allergens in the group tested with fragrance series, all except Ylang ylang oil werecomponents of fragrance mix I. Among the subjects tested with fragrance series, the top 5 commonallergens were individual components of fragrance mix I and Ylang ylang oil.Conclusion:A multicentre study would reflect better the pattern of allergen exposure of the nation. Furtherevaluation of the prevalence of contact allergy to DPG, CPPD, N-Cyclohexylthiophthalimide andYlang ylang oil would guide the need to incorporate these allergens in routine testing along with EBS.