Which items in urine sediment are the most clinically significant?
Feb 26, 2023
Source: Cainiu Health
Dr. Zhao Xinju
Introduction
The most significant findings in urine sediment generally include casts, epithelial cells, and white blood cells. The presence of casts in urine sediment examination usually indicates kidney damage, such as renal failure or nephritis. Moreover, different cast morphologies suggest different diseases; for example, red blood cell casts indicate renal hemorrhage, while white blood cell casts help differentiate pyelonephritis from cystitis.
The most clinically significant findings in urine sediment generally include casts, epithelial cells, and white blood cells.
1. Casts
The presence of casts in urine sediment analysis usually indicates kidney damage, such as renal failure or nephritis. Moreover, different cast morphologies suggest different diseases. For example, red blood cell casts indicate renal hemorrhage, while white blood cell casts help differentiate pyelonephritis from cystitis. Granular casts and waxy casts suggest progressive worsening of kidney lesions.
2. Epithelial Cells
The detection of epithelial cells in urine sediment may indicate renal parenchymal injury or inflammation of the urinary system. Conditions such as glomerulonephritis or urethritis require timely medical treatment.
3. White Blood Cells
If more than 10% of the white blood cells in urine sediment appear as "闪光细胞" (闪光 cells), it may indicate diseases of the urinary tract or surrounding organs, such as urinary stones, pyelonephritis, prostatitis, or vaginitis.
In addition, red blood cells are also important. Urine sediment examination can be performed at any time, but the midstream morning urine sample is preferred, with a volume of approximately 5–10 mL. It is important to ensure that the sample is free from contamination, as foreign substances—such as vaginal discharge in women—may affect test accuracy.
