Fig. 12

Histopathology of generalized canine discoid lupus erythematosus (a): in a skin biopsy from the trunk, a cell-rich lymphocytic interface dermatitis is present with prominent pigmentary incontinence. While epidermal atrophy (not shown) is classically seen in areas of prominent interface change, epidermal hyperplasia (shown here) can occur in chronic smoldering areas of lesions. 200X (b): inset box from image “a”, lymphocytes infiltrate predominately the basal layer in conjunction with basal cell vacuolation, apoptosis, and loss. 400X (c): some chronic lesions develop mild subepidermal fibrosis with a paucity of inflammation, while retaining pigmentary incontinence. 100X (d): inset box from image “c”, higher magnification image shows mild subepidermal fibrosis, few inflammatory cells and prominent pigmentary incontinence. 400X