erysipelas

A 65-year-old female with a history of diabetes, hypertension, obesity, chronic lymphedema and venous insufficiency presents to the ED with redness to her right leg noted 2 days ago but worsening since yesterday. She has had pruritus and swelling to the site accompanied by a painful burning sensation and a couple “painful knots” on her right inguinal region. She denies any prior history of deep vein thrombosis (DVT, IV drug use, or any history of vascular surgeries to the lower extremities. She has also had malaise for a few days and says that the redness has markedly increased since yesterday. On examination of the right lower extremity there is a large area of intense erythema with sharply demarcated borders that appears raised with some swelling and mild tenderness to palpation. What is the most likely diagnosis?