THE CLINICAL SPECTRUM OF MID-DERMAL ELASTOLYSIS AND THE ROLE OF UV-LIGHT IN ITS PATHOGENESIS

Background: We observed four patients with mid-dermal elastolysis (MDE) that was either precipitated or aggravated by UV light (UVL) exposure or was primarily confined to areas of UVL exposure. Objective. Our purpose was to report four cases of MDE occurring after significant UVL exposure and to demonstrate why we suspect that MDE in some instances may be photoinduced or photoaggravated. We also wish to demonstrate the varied clinical presentation of this disorder. Methods. Because all our patients had MDE involving skin exposed to UVL, biopsies were performed on clinically uninvolved sun-exposed and sun-protected skin in one patient to elucidate further the role of UVL in this process. Results: On routine histopathologic examination we found that uninvolved sun-exposed skin but not sun-protected skin demonstrated early MDE. Ultrastructural examination revealed a spectrum of elastic fiber changes in involved and clinically uninvolved sun-exposed skin. Phagocytosis of elastic fibers was not present. Conclusion: We conclude that UVL exposure was a major causative or aggravating factor of MDE in our patients and that the clinical appearance of this disorder is variable.