The buccal mucosae were not involved. Annular erythematous lesions were seen on the chest, arms, thighs and legs. The epidermis is largely necrotic and contains a subepidermal vesicle. Necrotic keratinocytes are present at the dermo-epidermal junction and throughout the epidermis. The upper dermis is edematous.
Extravasated erythrocytes are present in the papillary dermis and upper dermis.
The histological features favor a diagnosis of erythema multiforme. La 6.065 high positive. A further relapse followed at the beginning of May. Targetoid and annular erythematous purpuric lesions were seen on the upper chest, arms, forearms, hands, thighs and legs. Perniotic lesions with ulceration were seen on her fingertips. La 6.335 mid positive.