Pseudoxanthoma elasticum (PXE)-like papillary dermal elastolysis is a rare disorder clinically characterized by multiple, asymptomatic nonfollicular papules, yellow or flesh colored, grouped to form plaques with cobblestone appearance. These plaques are arranged symmetrically on the neck and supraclavicular areas of adult or elderly women, closely resembling the lesions of PXE. Histopathologically, the lesions are characterized by a band-like area of elastolysis along the papillary dermis. We report 2 cases of PXE-like papillary dermal elastolysis, in which the anomalies of the elastic tissue were immunohistochemically investigated with an antibody to the amyloid P component. This immunostaining demonstrated a band-like loss of elastic tissue along the papillary dermis. No clumping, fragmentation, or calcification of the elastic tissue was seen. We also review the literature about this rare process and discuss the differential diagnosis with other elastic tissue disorders that may show similar clinical and/or histopathologic findings.

Cutaneous lupus erythematosus may present as an isolated condition or as part of a systemic disease, being acute cutaneous lupus erythematosus, the skin manifestation, more closely related to systemic involvement. The histopathologic findings may show a wide variety of features, which show overlap among different clinical presentations. The exclusive involvement of the eccrine units, including eccrine coils, dermal ducts, and acrosyringia is extremely uncommon. We present the second case of systemic lupus erythematosus (SLE) with histopathologic involvement mostly located in the acrosyringia. The patient was a 37-year-old male with multiorgan failure who, in the context of flare-up of SLE, presented cutaneous lesions consisting of erythematous and edematous macules and plaques on the face, arms, and anterior chest. Histopathologic examination demonstrated necrotic keratinocytes confined to the acrosyringia as the main finding. It was associated with sparse inflammatory infiltrate in the superficial dermis, mostly composed of lymphocytes. The epidermis between the acrosyringia was spared. Our case was clinically almost identical to the one previously described, being a patient with a severe SLE and widespread cutaneous involvement and receiving treatment in the intensive care unit. The main differential diagnosis, both clinically and histopathologically was drug-related erythema multiforme. Clinicopathologic correlation is necessary to establish a correct diagnosis. SLE with histopathologic involvement mostly of the acrosyringia is a rare histopathologic variant of the disorder.