Patients with glomerulonephritis may have elevated blood pressure at all stages of the disease, but for different types of glomerulonephritis, the time point of elevated blood pressure may be slightly different. For example, in acute glomerulonephritis, elevated blood pressure may occur in the early stage of the disease, while in some patients with chronic glomerulonephritis, elevated blood pressure may occur in the middle or late stage of the disease. The mechanism of elevated blood pressure in glomerulonephritis patients is as follows: 1) When the glomerular filtration rate of the patient decreases, sodium and water are retained in the body, which causes volume-dependent elevation of blood pressure; 2) When the patient has a large amount of proteinuria, the decrease in the blood volume in the body can activate the renin-angiotensin-aldosterone system and the increase in the secretion of antidiuretic hormone, which can lead to the formation of renin hypertension.