Eczema and dermatitis: Pathogenesis

 Pathogenesis

The pathways leading to an eczematous reaction are likely to be common to all subtypes and to involve similar inflammatory mediators (prostaglandins, leukotrienes and cytokines;). Helper T cells, sometimes activated by superantigens from Staphylo-coccus aureus, predominate in the inflammatoryinfiltrate. 

One current view is that epidermal cytokines help to produce spongiosis; and that their secretion by keratinocytes can be elicited by T lym-phocytes, irritants, bacterial products and other stimuli (see Fig. 2.11).

 

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