Q. A 58-year-old man presents to the clinic with a three-day history of fever and a painful red rash on his right cheek. He reports that the redness started suddenly and has been expanding rapidly and spreading onto his ear. He also complains of fatigue. He is known hypertensive and on regular treatment. His temperature is 101°F (38.3°C), pulse 90 beats per minute, blood pressure 120/80 mmHg, and respiratory rate 16 per minute. The physical examination of the right cheek shows an erythematous tender raised lesion that is sharply demarcated from the surrounding normal skin. The lesion has expanded onto the earlobe and is markedly inflamed. The rest of the examination is normal. Given this clinical presentation, what is the most likely diagnosis?