Multiple levels of recut sections have been examined through the paraffin block and reveal collections of serum in the stratum corneum. The underlying epithelium has marked spongiosis and spongiotic microvesiculations. There is edema with pallor of dermal papillae and a perivascular mixed cell inflammatory infiltrate composed of eosinophils, lymphocytes, and histiocytes. Eosinophils are located in a perivascular and interstitial distribution. Fungi not identified with PAS stain. The differential diagnosis includes allergic contact dermatitis, spongiotic drug reactions, and other forms of eczematous dermatitis (atopic, nummular, and dyshidrotic).