ABSTRACT

I. Introduction 233

II. Classification and Definitions 237

III. Contact Urticaria and Exogenous Dermatitis 238

A. Contact Urticaria leading to Secondary Hand Dermatitis (CU′ 2° HE)

B. Concomitant Contact Urticaria and Allergic Contact Dermatitis (CU-ACD)

C. Concomitant Contact Urticaria and Irritant Contact Dermatitis (CUICD)

D. Protein Contact Dermatitis (PCD) 239 E. Latex Glove Contact Urticaria (LGCU) 240

IV. Contact Urticaria and Exogenous Dermatitis 241

A. Concomitant Contact Urticaria and Atopic Dermatitis 241

V. Clinical Features 241

VI. Diagnostic Methods 242

VII. Conclusion 243

References 243

I. INTRODUCTION

Contact urticaria syndrome (CUS), first defined as a biologic entity in 1975,1 comprises a heterogeneous group of transient inflammatory reactions appearing within minutes to hours after contact with the eliciting substance. This reaction may occur on normal or eczematous skin and usually disappears within a few hours. Symptoms cover a spectrum (Table 17.1a). At the weakest end, patients may experience itching, tingling, or burning accompanied by erythema (wheal and flare). At the more extreme end of the spectrum, extracutaneous symptoms may accompany the local urticarial response, ranging from rhinoconjunctivitis to anaphylactic shock.2 The mechanisms underlying contact urticaria are divided into three main types; namely, immunologic (IgE mediated), nonimmunologic, and unclassified3 (Table 17.1b).