Evolution of granuloma annulare to mid-dermal elastolysis: report of a case and review of the literature.

A 55-year-old healthy Caucasian female, on no medication, was seen by a dermatologist because of a patchy, slightly indurated and violaceous eruption involving her neck and trunk. The clinical impression was of granuloma annulare (GA). Over a period of several months the violaceous lesions became atrophic with loss of colour and eventual wrinkling of lesional skin. Sequential skin biopsies were obtained, which revealed a spectrum of changes. Those from early violaceous lesional zones displayed perivascular lymphocytic infiltrates and interstitial granulomatous inflammation, characteristic of interstitial GA. Samples from atrophic lesional areas appeared normal on routine sections but an Orcein-Giemsa (OG) stain, prompted by the clinical history of atrophy, revealed absence of elastic fibers in the mid-reticular dermis. The combined clinicopathologic findings pointed to development of mid-dermal elastolysis (MDE) at involutional sites of GA. Owing to consideration of a cutaneous T-cell lymphoma in the differential diagnosis, genotyping in search of T-cell monoclonality was performed and yielded a negative result. Our case supports the existing but scant evidence in the literature that the rare, enigmatic condition termed MDE is an end-result of inflammatory destruction of dermal elastic fibers. GA is one form of dermatitis capable of culminating in this entity, but others have also been implicated.