Electron-microscopy of granuloma anulare and necrobiosis lipoidica [ZUR ULTRASTRUKTUR DES GRANULOMA ANULARE UND DER NECROBIOSIS LIPOIDICA]

Abstract

The aim of our research was to set up a definite histological differentiation between necrobiosis lipoidica and granuloma anulare. 26 cases of necrobiosis and 20 cases of granuloma were histologically studied; out of these, 11 and 12 cases, resp., were selected for electron-microscopic investigation. We comparatively evaluated those histological features which might serve as differentiation criteria, i.e., the connective tissue, inflammatory cells, deposits of lipoids, necrosis, and regeneration. Generally, our results showed only gradual differences between the diseases: Necrobiosis lipoidica was characterized by giant cells and plasma cells and, in most cases, by necrosis, whereas granuloma anulare showed structural changes in nerve fibres.