Renal tubular damage can be detected by some blood and urine laboratory tests, including urinary β2-microglobulin assay, α1-microglobulin assay, retinol-binding protein assay, urine specific density, urine osmolality (urine osmolality) assay and so on.
1. Urine β2-microglobulin measurement: 99.9% of β2-microglobulin is reabsorbed in the proximal tubules of the kidney, so an increase in the amount of β2-microglobulin in the urine can very sensitively reflect the impaired reabsorption function of the proximal tubules of the kidney.
2. α1-microglobulin measurement: free α1-microglobulin can freely pass through the glomerulus, and about 99% of it is reabsorbed and decomposed in the proximal tubule through the cytosol, so an increase of α1-microglobulin in the urine can reflect the impaired reabsorption function of the proximal tubule in a very specific and sensitive way.
3. Determination of retinol-binding protein: retinol-binding protein is filtered out from the glomerulus, and most of it is reabsorbed and broken down by the renal proximal tubule, therefore, elevated retinol-binding protein in urine can be seen in the early stage of renal proximal tubule injury.
4. Determination of urine specific density and urine osmolality: the distal tubules of the kidney mainly concentrate and dilute urine, therefore, abnormal urine osmolality or urine specific density often reflects the impaired function of the distal tubules of the kidney.
If the patient has any discomfort, it is recommended to consult a regular hospital in time and follow the doctor’s instructions for standardized treatment.