Psoriasis
Fully developed
| Sparse superficial perivascular infiltrate of mostly lymphocytes |
| Slight edema of the papillary dermis |
| Dilated tortuous capillaries in dermal papillae |
| Slight epidermal hyperplasia |
| Some mitotic figures in keratinocytes above the epidermal basal layer |
| Spongiosis in company with a few lymphocytes in discrete foci in the lower part of the epidermis |
| Spongiform and subcorneal pustules within the epidermis of some lesions |
| Hypergranulosis in some foci |
| Mounds of parakeratosis with neutrophils at their summits staggered within the stratum corneum, sometimes beneath the retained original cornified layer with its basket-woven configuration |