S1-Guideline for diagnosis and therapy of necrobiosis lipoidica.

Necrobiosis lipoidica (NL) is a rare granulomatous skin disease of unknown etiology that occurs frequently in association with diabetes mellitus and other comorbidities. The predilection site is the lower leg, particularly the pretibial areas. The exact pathogenesis remains unclear. Vascular disorders with microangiopathic changes and an autoimmune genesis are discussed. Necrobiosis lipoidica occurs three to six times more frequently in women. Men tend to show a more severe course and develop ulcerations more frequently. The diagnosis can often be established based on typical clinical and dermatoscopic findings. A biopsy should be performed in clinically unclear cases, in the presence of ulceration, or if there are signs of malignant transformation. Overall, the scientific data available for NL are still insufficient and there is a need for further research. However, as patients often experience a severely impaired quality of life, it is important to be aware of the limited scientific evidence and to translate it into practical therapeutic recommendations. This short version of the S1 guideline of the German Dermatological Society (DDG) summarizes the current evidence and, incorporating expert assessments, provides specific recommendations for everyday clinical practice.