Erythematous plaques due to platelet plugging: a clue to underlying myeloproliferative disorder.

We report a syndrome in a middle-aged woman characterized by tender erythematous plaques with histologic evidence of dramatic dermal vessel occlusion. These cutaneous findings occurred in association with progressive inferior vena cava and portal vein thrombosis while on coumarin anticoagulation, following hepatic transplantation for Budd-Chiari syndrome. The material occluding dermal vessels was proven by immunohistochemical staining to be platelet plugs. These findings led to the diagnosis of an underlying myeloproliferative disorder explaining both her cutaneous and liver abnormalities and institution of appropriate platelet directed anticoagulation with aspirin.