clinical features
Last reviewed 03/2021
Necrobiosis lipoidica usually affects the skin on the lateral and anterior surfaces of the lower legs and rarely, the arms and trunk. Over the shins, it may be mistaken for venous incompetence.
The lesions may be single or multiple, unilateral or bilateral. They begin as a small, dusky red, elevated nodule with a sharply circumscribed border. Slowly, it enlarges and becomes irregular, flattened and depressed. Except for the border, the colour becomes brownish yellow.
The epidermis is smooth or slightly scaly and atrophic. Delicate vessels may be observed through the surface. Long standing lesions may show ulceration, fibrosis and scarring.
Early lesions may resemble sarcoid or granuloma annulare.