ABSTRACT
I. Introduction 505
II. Clinical Overview 506
III. Differential Diagnosis 509
A. Hand Psoriasis versus Contact Dermatitis of the Hands 509
B. Other Differential Diagnoses 511
IV. Treatment 512
V. Concluding Remarks 514
References 515
I. INTRODUCTION
Psoriasis is commonly considered to be distinctive and accurately diagnosable on morphological grounds. Clinical experience, however, demonstrates numerous exceptions. As a clinical diathesis of heterogeneous morphology, psoriasis can mimic different diseases. Hand psoriasis represents a characteristic, morphologic localized variant, frequently portraying eczematous features, which is often labeled as chronic hand dermatitis. This label is sometimes partially correct, because irritants or allergens may cause a superimposed contact dermatitis1 and a significant overlap between psoriasis and the eczematous dermatoses. Maibach and Epstein1 coined the term “eczematous psoriasis” to describe this overlap. Eczematous psoriasis may be the result of a superimposed exogenous factor (i.e., secondary eczematous psoriasis). The exogenous factors are frequently irritants, but may also be allergens. Conversely, primary eczematous psoriasis represents a totally endogenous process. In this case the eczematous features are part of the
spectrum of psoriatic skin changes.2 Eczematous hand psoriasis should be considered when dealing with hand dermatitis, especially the chronic and difficult-to-manage variety.
