[Histopathology of erythema nodosum]

The histopathology of erythema nodosum is discussed with reference to the literature and of 19 cases of our clinic. There is a significant vascular involvement especially of the subcutaneous tissue. The veins and arteries are equally affected. The histological picture consists not only of an acute inflammatory process in the subcutaneous tissue, but also of inflammatory cells which area see to a lesser extent in the dermis. In many cases the typical small granulomatous foci of MIESCHER which are considered to be pathognomonic for erythema nodosum do not develop. In the cases which we examined we were not always able to tell from the histological picture how long the erythema nodosum had been present. Multinucleated giant cells which are often found in the septal connective tissue are seen even in relatively acute cases.