clinical appearance of the different stages of eczema mirrors their histology.
In the acute stage, oedema in the epidermis (spongiosis) progresses to the
formation of intraepidermal vesicles, which may co-alesce into larger blisters
or rupture. The chronic stages of eczema show less spongiosis and vesication but
more thickening of the prickle cell layer (acanthosis) and horny layers
(hyperkeratosis and parakeratosis). These changes are accompanied by a variable
degree of vasodilatation and infiltration with lymphocytes.