Thelansis

  Necrobiosis lipoidica (NL) is a rare granulomatous disease characterized by collagen degeneration, often associated with diabetes mellitus, primarily type 1. Thickening of blood vessel walls and fat deposition are standard features. Ulcer formation, typically following trauma, is the main complication, occasionally complicated by infections or, rarely, squamous cell carcinoma in chronic cases. The exact cause of NL is unknown, but vascular disturbance with immune complex deposition or microangiopathic changes leading to collagen degeneration is the prevailing theory. Vascular abnormalities in NL lesions often involve thickened vessel walls, fibrosis, and endothelial proliferation, particularly in diabetic patients. Clinical presentation of NL is distinct, though atypical appearances can complicate early recognition. Important differential considerations include acute sarcoidosis complications, granuloma annulare, hematologic malignancies, paraproteinemia, rheumatoid arthri...