Patients with hypertension-induced renal damage have normal routine blood and urine tests before the development of clinical symptoms such as proteinuria and increased nocturia, but the application of more sensitive tests can reveal some abnormalities, which are the early renal damage of essential hypertension, including: 1. Increased urinary microalbumin excretion Especially seen in patients with essential hypertension that is not adequately controlled and newly developed severe hypertension, to be It can be reduced after blood pressure is controlled. Increased urinary sediment erythrocyte counts can be observed with phase contrast microscopy as a result of hypertension-induced damage to the glomerular capillary filtration barrier. 3, Increased urinary β2 microglobulin excretion β2 microglobulin is now recognized as a sensitive indicator for measuring glomerular filtration rate and tubular reabsorption function. Newly discovered patients with severe hypertension and elderly patients with hypertension can have a significant increase in urinary β2 microglobulin, which can decrease after blood pressure control. 4, urinary NAG excretion increased renal tubular and urinary epithelial cells containing NAG, the amount of urinary excretion in renal damage can be up to 1200 times, and can be reduced after blood pressure control.