Resolution and repair of elastic tissue calcification in pseudoxanthoma elasticum

Biopsy specimens of a skin lesion from a patient with pseudoxanthoma elasticum were obtained at the beginning and end of a 1 1/2-year period of clinically documented regression of the lesion. Light microscopic studies of these specimens showed that, during the period of regression, there was a decrease in the number of abnormal calcified elastic fibers in the dermis. Electron microscopic findings were interpreted as indicating breakdown and removal of mineralized elastic fibers at the beginning and formation of new elastic fibers at the end of the regression period. Cytoplasmic processes of active fibroblasts were intimately associated with fibers undergoing dissolution. The case thus represents a clinically and morphologically documented example of resolution and repair of elastic tissue calcification.