| Abstract: | Since, in dermatological literature, the term ‘dermatitis’ is frequently confused with ‘eczema’, is has to be unequivocally stated that ‘dermatitis’ is a generic term covering very different patterns of dermal inflammation, whereas ‘eczema’ (or ‘eczematous dermatitis’, resp.) represents a distinct pattern of superficial dermatitis histologically characterized by spongiotic dermo-epidermitis. Eczemas can be defined as inflammatory, non-infectious intolerance reactions of the epidermo-papillary skin compartment with reversible epidermotropic exudation caused by an immense variety of external and/or internal agents combined with increased individual susceptibility to respond. As current classifications only partially reflect the complex causative conditions involved in the etiology and pathodynamics of eczematous disease, the author proposes to classify eczemas according to the following major categories: 1) Mainly exogenous eczemas including those of contact-induced non-allergic, allergic and photo-allergic origin, 2) mainly endogenous (or atopic, resp.) eczemas, and 3) eczemas of combined dysregulatory-microbial origin. The latter group comprises eczemas caused by various functional and/or structural derangements of epidermal protective properties (summarized by the term ‘dysregulation’) which in turn permit the resident and/or transient microflora of the damaged horny layer to induce eczematous inflammatory responses. Since topical and morphological attributes may change during the course of the very same eczema, they are inappropriate for basic classification and should be used only as minor criteria for characterizing the sites and predominant lesional type of the respective eczema. The possible combination of eczemas representing two or even three major categories in one patient leads to intermediate forms entirely in keeping with the division into three principal groups. The proposed classification is aimed at eliminating the terminological confusion of eczemas as well as enabling reliable documentation for statistics which can be used in computer-aided comparisons of multicenter studies on etiology or epidemiology of eczemas. |
