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

Approach to the Patient with a Skin Disorder Part 6 Dermatitis herpetiformis.. Vesicles are often excoriated due to associated pruritus.. The shape of lesions is also an important feat

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, target-shaped 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 irritant dermatitis In contrast, lesions with a generalized arrangement are common and suggest a systemic etiology

Figure 52-9

Erythema multiforme

This eruption is characterized by multiple erythematous plaques with a target or iris morphology It usually represents a hypersensitivity reaction to drugs

(e.g., sulfonylamides) or infections (e.g., HSV) (Courtesy of the Yale Resident's

Slide Collection; with permission.)

Figure 52-10