ABSTRACT
I. Introduction 32
II. Demographic Characteristics of Hand Eczema 33
III. Exogenous Risk Factors 34
IV. Endogenous Risk Factors 38
A. The Relationship between Hand Eczema and Atopy 38
B. Atopic Skin Diathesis and Hand Eczema 39
1. Study 1 41
2. Study 2 41
C. Metal Sensitivity, Atopy, and Hand Eczema 46
V. Hand Eczema and Occupational Skin Diseases 47
References 49
I. INTRODUCTION
Although eczema of the hand is one of the most common skin diseases, a clear and worldwide accepted definition of what is included as “hand eczema” (HE) does not exist, and even dermatologists differ in their interpretation. After having excluded disorders of known etiology (e.g., tinea manuum, scabies), well-defined noneczematous morphology (e.g., psoriasis, lichen planus, granuloma annulare, porphyria cutanea tarda, keratosis palmo-plantaris, fixed drug eruption), and neoplastic disorders from the category of HE, and if hands are not involved as part of an extensive skin disorder, the diagnosis of characteristic and established
cases of HE usually presents little difficulty. Yet opinions differ on the validity of including mild and transient cases or those in which dryness, cracking, and superficial fissuring are the only features.1 It is also difficult to subclassify HE according to morphologic, etiologic, or pathogenetic classifications used in dermatology.2 HE is a multifactorial disease in which both exogenous and endogenous factors play a role. General aspects of those risk factors in HE will be considered in this chapter. In addition to the fact the HE is not a single entity but an affliction with multiple causes,2 an attempt to discuss the general role of risk factors by the literature poses additional problems: some studies are based on selected samples, as with patch test patients or special occupational groups (e.g., hairdressers, nurses), other population-based studies are based on questionnaires, and often control groups were not included. Finally, there is no clear agreement on the definition of endogenous risk factors, such as an atopic skin diathesis (ASD), which is often believed to be related to HE.2-15 In this chapter some demographic characteristics of patients with HE will be introduced, and general aspects of exogenous and endogenous risk factors of HE will be reported according to several studies.
