Papular mucinosis (scleromyxoedema) complicating diffuse systemic sclerosis: clinical features and electron microscope observations.

Papular mucinosis (scleromyxoedema) is an uncommon disorder characterized by generalized papular eruption and cutaneous induration, which may be associated with a variety of extracutaneous manifestations. Although scleroderma and papular mucinosis share many features, they are clinically and histologically distinct entities. We report here a patient with diffuse scleroderma who developed superimposed papular mucinosis. Degranulating mast cells were a prominent ultrastructural finding in the involved skin. The occurrence of scleroderma and papular mucinosis, two uncommon cutaneous indurative diseases, in the same patient has not been described previously.