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. | 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 irritant dermatitis. In contrast lesions with a generalized arrangement are common and suggest a systemic etiology. Figure 52-9 Source I Fauci as Kjjptr DL. BrtU ñutid E. H u r L. Longo PL. Jtmeion JL Loictlto J Hansen t Medion 17th Edition http Copunghrt O Th Htsrtw-Hjl comptnitf. inc. All rightr Erythema multiforme. This eruption is characterized by multiple erythematous plaques with a target or iris morphology. It usually represents a hypersensitivity reaction to drugs . sulfonylamides or infections . HSV . Courtesy of the Yale Resident s Slide Collection with permission. Figure .
