Urine is a type of excrement, a waste product of animals and humans excreted by the kidneys.

In the kidneys, as a result of blood filtration, reabsorption and secretion, urine is formed, then it flows down the ureters into the bladder or cesspool. Of these, urine is excreted.

Physico-chemical properties of urine

•On average, human urine has a density of 1005-1030 g/L, pH – from 4.8 to 7.5.

•In humans, normal urine is transparent, light yellow in color. Urobilin gives it a yellow color.

•91-96% of human urine consists of water. It contains nitrogenous breakdown products of protein substances: urea, uric and hippuric acids, creatinine, xanthine, urobilin, indican, as well as salts - mainly chlorides, sulfates and phosphates.

•Organic components in urine:

•Urea (20 - 35 g)

•Ketone bodies (<3 g)

•Amino acids (1 - 3 g)

•Creatinine (1 - 1.5 g)

•Uric acid (0.3 - 4.99 g)

•Glucose (<0.16 g)

•Protein (<0.15 g)

•Hippuric acid (0.15 g)

•Creatine (0.05 - 0.1 g)

•Inorganic components:

•Cations (K , Na , Ca² , Mg² , NH ,)

•Anions (Cl¯, SO ²¯,НРО²¯)

•Other ions (in small quantities)

Proteinuria

•Normally, proteins with a molecular weight of up to 70 kD pass through the renal filter, i.e. albumin, immunoglobulin light chains, many enzymes.

•An increase in protein in the urine is called proteinuria, which is the main syndrome of renal pathology.

•There are renal and extrarenal proteinuria. Renal proteinuria is divided into functional and organic. Prerenal, renal and postrenal proteinuria are also distinguished.