Ultrastructural alterations of elastic fibers and other dermal components in ehlers-danlos syndrome of the hypermobile type.

Ehlers-Danlos syndrome (EDS) is a heterogeneous group of connective tissue disorders with varied molecular abnormalities. Some morphologic alterations are described in collagen and elastic fibers. We report on previously undescribed ultrastructural changes in the elastic fibers found in the skin of 22 of 29 patients suffering from the hypermobile type of EDS. They existed in variable combinations of a fragmented appearance with frayed contours, internal microcavities, some elastotic-like changes, and discrete calcified foci. The collagen fibrils and their bundles were also altered with morphologic aspects reminiscent of those found in the classical type of EDS. Large globules of hyaluronic acid were also dispersed in the amorphous matrix.