Localized involutional lipoatrophy: report of six cases.

We herein report six cases of localized involutional lipoatrophy, who presented with a depressive plaque on the lateralis of the upper arm. All patients were female, and three had previous injections for allergic rhinitis at the affected sites before the development of lipoatrophy. One patient received intramuscular injection at the affected site when she had a cold. Histological examination showed fat lobules composed of small lipocytes in the hyaline connective tissue. Immunohistochemical examination revealed a number of CD68-positive macrophages in the fat lobules. We consider that localized involutional lipoatrophy is more common than has been reported, and is occasionally induced by local injections.