Normally, urinary protein levels are very low: within 24 hours, the proteins eliminated in the urine should not exceed 200 mg. In some cases, these values can temporarily increase, without giving rise to particular concern. This can happen, for example, after strenuous physical activity or when you are sick.
In other circumstances, high proteinuria requires further investigation to determine if there is a more severe health problem, such as kidney damage, at the basis of this finding.
The increase in protein in the urine could also be due to various other conditions, such as: anemia, heavy metal poisoning, cystitis, diabetes, gout and pregnancy.
In the blood of each individual, many proteins circulate, which are nothing short of essential for the organism; in fact, they perform transport (nutrients, gases, hormones, etc.), immune (defense against viruses, bacteria, etc.) and regulatory functions. (metabolism, coagulation, pH and blood volume etc.).
At the kidney level, the blood is purified of waste products and excess substances, undergoing a sort of sieving; the meshes of this very fine sieve are crossed by numerous substances, which end up in the filtrate to be reabsorbed or expelled through the urine, according to biological needs. All these substances do not include proteins, which, with the exception of the smaller ones, are almost absent in the filtrate and in the urine.
In the course of life it may happen that - due to pathologies or other problems (hypertension, diabetes, kidney infections, congenital malformations, etc.) - the meshes of the kidney sieve loosen, allowing greater quantities of protein to pass. Consequently, the protein concentrations of the urine - evaluated through a common examination on a urine sample - increase significantly.
Based on the recorded value, by analyzing the urine collected over 24 hours, doctors talk about:
- Microalbuminuria (30-150 mg) *
- Mild proteinuria (150-500 mg) *
- Moderate proteinuria (500-1000 mg)
- Severe proteinuria (1000-3000 mg)
- Proteinuria in the range of nephrotic syndrome (> 3500 mg)
* Proteinuria is defined as a "urinary excretion of proteins greater than 150 mg per day; other sources raise this threshold to 300 mg, so that below 300 mg / day we speak of microalbuminuria and above 300 mg / day we speak of of proteinuria.
early kidney disease.For this reason, the finding of proteinuria should never be neglected, under penalty of ignoring a potentially progressive nephropathy towards renal insufficiency.
