A 62-year-old woman undergoes treatment for bilateral gonarthrosis and has been regularly taking diclofenac sodium for 2 years. During the last six months she notes elevations of her blood pressure to 160/100 mm Hg. X-ray of the knee joints shows decreased height of the inter-articular space, marginal growths on the articular surfaces, and epiphyseal osteoporosis. General urinalysis shows the following specific gravity - 1010, erythrocytes-5-6 in sight, leukocytes - 10-12 in sight, casts (cylinders)-0-1 in sight, glucose-not detected, protein - 0.22 g/L. Fasting plasma glucose - 63 mmol/L What is the most likely cause of the changes observed in the general urinalysis?