Ultrastructural evaluation of mid-dermal elastolysis.

Mid-dermal elastolysis is a well-defined clinical and histopathologic entity manifested by fine wrinkling of the skin and a mid-dermal loss of elastic fibers. Ultrastructural and histologic studies were performed in an attempt to better define the cause of the elastolytic process. Biopsy specimens from the lesions of 3 patients with mid-dermal elastolysis were studied at light and electron microscopic levels. Ultrastructural evidence of normal elastic fiber engulfment by activated macrophages was observed; however, some fields also demonstrated envelopment of abnormally degenerated elastic tissue. Although there are many potential causes of this degeneration, photodistribution of the lesions suggests that ultraviolet damage is a primary inciting factor.