The specific weight of the urine, also called specific gravity, indicates the concentration of the urine.
An increased specific gravity means that the urine is very concentrated and there was probably too little drinking. Also large loss of fluid due to heavy sweating or diarrhoea leads to a higher specific gravity of the urine.
With a high amount of drinking, the urine is diluted and the specific gravity decreases.
For the maintenance of the fluid and electrolyte balance (homeostasis) in the body, the ability to concentrate and dilute the kidneys is crucial. This can be determined by the specific gravity of the urine.
However, the specific gravity of urine is also important for the interpretation of other measured values in the urine, such as.B protein, blood, nitrite, glucose and leukocytes. It should be taken into account in order to avoid misinterpretation due to excessive or low urine concentration.
In addition, it can be determined whether a urinalysis should be intentionally falsified. Due to extremely high drinking amounts and thus dilution of urine, e.B. in doping tests in the sports sector or in drug tests, attempts are repeatedly made to influence the results.
The normal specific weight of the urine varies between 1,001g/ml and approximately 1.04 g/ml.
If the value deviates upwards or downwards during a single measurement, this is not necessarily an indication of a disease, since the density depends strongly on the fluid intake.
Depending on the measurement method, protein, sugar, blood,X-ray contrast agents or infusions can increase the specific gravity of the urine.
