Vascular changes in morphea.

Vascular changes in morphea were studied in skin biopsies from 14 patients. Small vessels with pericytes present the changes in three different patterns. The first was the endothelial cells in a stimulated condition and thickened vascular wall with infiltrating macrophages and mast cells. The second was characterized by thick basal lamina of pericytes and the third by activated pericytes with infiltrating lymphocytes and plasma cells. Otherwise, all patterns showed altered endothelial cells and infiltrating macrophages and mast cells similar to the first pattern. The first pattern was mostly found in uninvolved skin. The second and the third were found in the inflammatory and sclerotic areas. It seems, therefore, that activated pericytes are the most essential changes in vessels of morphea. Probably, muscular vessels are simply involved in the fibrotic process.