Pseudoxanthoma Elasticum-Like Papillary Dermal Elastolysis: A Single Case Report

Background: Pseudoxanthoma elasticum-like papillary dermal elastolysis (PXE-PDE), a rare acquired elastolytic disorder, occurs in postmenopausal, elderly women and is characterized by soft, white-yellow papules that localize on the neck and supraclavicular regions and often coalesce into cobblestone plaques. It has no systemic involvement and is histologically distinct from the clinically similar inherited pseudoxanthoma elasticum. Case Summary: A 64-year-old Caucasian woman presented with a 2-year history of multiple, asymptomatic soft yellow 1-to 2-mm papules on her neck, which were increasing in number. On histopathology, haemotoxylin and eosin stain showed a normal-appearing papillary dermis; however, Verhoeff-van Gieson elastic stain showed absent elastic fibres in the papillary dermis. Papular elastorrhexis was suggested, but given its clinical picture, PXE-PDE was also considered. There was no resolution after 2 courses of intralesional triamcinolone acetonide (0.1 mL of 5 mg/mL). Conclusion: PXE-PDE, which is characterized by complete loss or significant reduction of elastic fibres in the papillary dermis, was consistent with our patient's presentation and histologic findings. Papular elastorrhexis, a paediatric cutaneous disorder, was initially considered, but clinicopathologic correlation led to a diagnosis of PXE-PDE. Intralesional corticosteroids was tried as a treatment but was ineffective at improving the condition. This report documents the importance of histopathology and clinicopathologic correlation when differentiating the overlapping variants of fibroelastolytic disease.