Specific gravity of urine in norm and in pathology

You were given research results in the laboratory. What can a person with little understanding in medicine look at these incomprehensible figures? First of all, confusion. Certainly, it is not very difficult to determine the increase or decrease of a given indicator, since the normal values are indicated in the same form. In order to interpret the figures obtained, certain knowledge is required. Let's take a well-known analysis of urine. The first thing that attracts attention is the specific gravity of urine. What does this indicator show?

The specific gravity of urine (it is also called the relative density of urine) shows the ability of the kidneys to concentrate in the urine substances intended for removal from the body. These include, in particular, urea, uric salts, uric acid and creatinine. Specific gravity of urine in the norm is in the range from 1012 to 1027, it is determined with the help of a urometer. The measurement is carried out in the laboratory. Recently, the determination of urine density is carried out on special equipment using the methods of dry chemistry.

If the fluid is released from the body more than normal, the concentration of dissolved substances in the urine decreases. Consequently, the specific gravity of urine decreases. This condition is called hypostenuria. It can be noted in healthy people who consume large amounts of liquid after taking diuretic food (watermelons, melons). For fans of different diets, a decrease in the index may appear (due to a lack of protein food in the diet, especially when fasting).

With various diseases of the kidneys, their ability to concentrate various substances in the urine is disturbed, so the decrease in specific gravity is due not to excessive fluid intake, but to a violation of kidney function (pyelonephritis or glomerulonephritis, nephrosclerosis). Hypostenuria occurs in patients in the period of resolution of edema or effusions, when the fluid accumulated in the tissues quickly leaves the body. Reducing the density of urine happens during the intake of diuretics. Monotonous specific gravity during the day should alert the doctor with regard to pyelonephritis (especially in combination with night urine excretion).

An increase in the relative density above 1030 is called hypersthenuria. A similar condition occurs in people with insufficient fluid intake. The specific gravity of urine, the norm of which is directly proportional to the drinking regime of a person, can rise during the hot season, when a person sweats profusely, therefore, loses a lot of moisture. High figures of this laboratory indicator are typical for workers in hot shops: cooks, smiths, metallurgists.

Hyperstenuria also occurs when the blood thickens, which happens due to profuse vomiting or diarrhea. Patients with cardiac diseases accumulate fluid in the body, resulting in decreased diuresis and increased specific gravity of urine. Patients with diabetes often find high numbers of specific gravity in laboratories. In this case, this indicates a large amount of glucose in the urine.

The indicator also indirectly indicates how much the patient adheres to the drinking regime recommended by him. This is important for patients with kidney disease and urolithiasis.

A single change in the indicator is not critical for the diagnosis, since daily fluctuations in specific gravity may range from 1004 to 1028, and this is normal.