If there are excessive ketone cells in the blood (e.g. by a strict low-carbohydrate diet, a lack of insulin in the blood or insulin resistance of the cells), they are excreted by the kidneys with the urine.
The increased appearance of ketone bodies in the urine is also called ketonuria.
Ketones basically have acidic properties. The body reduces acidification by too many ketones via various buffer systems such as urine, breath and blood.
The detection of ketone bodies in the urine is an important indication of a metabolic derailment, e.g. in diabetics. Such a derailment can lead to diabetic ketoacidosis (acid poisoning) and this can end up a life-threatening coma.
Other diagnostic options:
- Detection of famine
- Control and detection of certain diet programs where the carbohydrate intake is drastically reduced (e.g. low-carb diets)
- Detection of hyperemesis gravidarum (frequent vomiting during pregnancy)
In healthy people and a balanced diet, only very low concentrations of ketone can be detected in the urine, usually no more than 0.5 mmol/l.
Very high concentrations of ketone in the urine can be found in the following diseases or situations:
- untreated or poorly adjusted diabetes mellitus
- high fever
- major injuries, also after surgery
- high-fat diet, thus increased fat metabolism
Ketone bodies can be detected relatively easily in the urine via ketone test strips. However, one should also pay attention to the water balance during the measurement, as this can have a great influence on the concentration of the ketones in the urine.