Chapter 052. Approach to the Patient with a Skin Disorder (Part 6)

Dermatitis herpetiformis. This disorder typically displays pruritic, grouped papulovesicles on elbows, knees, buttocks, and posterior scalp. Vesicles are often excoriated due to associated pruritus. The shape of lesions is also an important feature. Flat, round, erythematous papules and plaques are common in many cutaneous diseases. However, targetshaped lesions that consist in part of erythematous plaques are specific for erythema multiforme (Fig. 52-9). In the same way, the arrangement of individual lesions is important. Erythematous papules and vesicles can occur in many conditions, but their arrangement in a specific linear array suggests an external etiology such as allergic contact (Fig. 52-10) or primary...