A 58-year-old woman presents with 1 week of bilateral lower limb edema, oliguria, nausea, vomiting, and blurred vision. BP 190/138 mmHg. Facial expression rigidity, thickened hand skin, ESR 48 mm at the end of the first hour. Urinary protein (++) (3-4 g/d), urine sediment RBC 5-8/HPF, Scr 600 μmol/L. Bilateral enlarged kidneys. The clinical diagnosis is: