Urine
Urine screening
Laboratory screening of ten urine parameters, including protein, glucose, blood cells, nitrite, pH and specific gravity. You collect the sample at home.
€ 35,00
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Urine tests · Urine
Ketones
Ketones in the urine; formed when the body burns fat instead of sugar, for example during fasting or with poorly controlled diabetes.
At a glance
- Measured in urine
- In 1 test panel
- Check the preparation
Explanation
Ketones: what is measured?
Ketones are breakdown products of fat. The body makes them when too little glucose (sugar) is available as fuel, or when it cannot use it due to a lack of insulin. The pad on the dipstick mainly reacts to acetoacetate, one of the three ketones; beta-hydroxybutyric acid, which is made the most in poorly controlled diabetes, is not detected by the dipstick.
What can it detect?
- Fasting, a low-carbohydrate or ketogenic diet, or prolonged vomiting
- Poorly controlled diabetes with a risk of ketoacidosis (acidification of the blood by ketones)
Result
What does the result mean?
Positive result
Ketones in the urine are usually caused by fasting, a low-carbohydrate or ketogenic diet, not eating for a long time due to illness or vomiting, or prolonged heavy exercise; they are also more common during pregnancy. This is then a normal reaction of the body. In diabetes, especially type 1, or when using an SGLT2 inhibitor, ketones may point to a serious lack of insulin. Together with nausea, vomiting, abdominal pain, a lot of thirst, rapid breathing or drowsiness, this can fit ketoacidosis; that is an emergency.
Negative result
A negative result is normal. Because the dipstick does not detect beta-hydroxybutyric acid, it can still be negative in early ketoacidosis; in diabetes and illness, ketones are therefore preferably measured in blood.
After an abnormal result
With ketones without diabetes and with a clear cause, such as fasting or a low-carbohydrate diet, usually no follow-up is needed. With ketones together with glucose in the urine or symptoms of high blood sugar, a blood test for glucose follows quickly, and with signs of illness a doctor assesses the same day whether there is ketoacidosis.
Reliability
How reliable is the test?
A urine dipstick is a quick screening and not a diagnosis. According to the Dutch GP guideline (NHG) on urinary tract infections, the dipstick is a first step with symptoms that fit a bladder infection; if in doubt, a culture or sediment test follows. For detecting kidney damage, the dipstick is less sensitive than the albumin-creatinine ratio in urine and the eGFR in blood; the NHG guideline on chronic kidney damage is based on those. In people without symptoms, most abnormal dipstick results are temporary or harmless; a single abnormal result therefore says little.
What can affect the result?
- Sample collection: preferably use first morning urine or urine that has been in the bladder for at least 4 hours, and after washing, catch the middle part of the stream (midstream), so that no discharge or skin bacteria get into it.
- Menstruation, and the days before and after it, often gives a positive result for blood and sometimes for leukocytes and protein; it is better to collect at another time.
- Vitamin C (supplements or a lot of fruit juice) can suppress the reaction for blood, glucose, nitrite and bilirubin and give a false negative result.
- Heavy exercise, fever and dehydration in the day before sample collection can temporarily cause protein, blood or ketones. Urine that has been standing for a long time or has become warm gives less reliable results, especially for nitrite, bilirubin, urobilinogen and pH.
Preparation
- Preferably use the first morning urine, or urine that has been in your bladder for at least 4 hours.
- Collect the middle part of the stream.
- Do not collect urine during your period.
Who it is for
Who is the test useful for?
Useful for
Useful with symptoms that may fit a bladder infection, such as frequent and painful urination, or as a simple addition to blood tests for the kidneys, sugar or liver. For detecting kidney damage in diabetes or high blood pressure, the albumin-creatinine ratio in urine says more than the dipstick. In people without symptoms and without risk factors, the chance of a harmless abnormality is greater than the chance of a real condition.
How common is it?
Bladder infection is one of the most common infections in women; in men it is much less common. Chronic kidney damage occurs in about 1 in 10 adults, usually without symptoms. In people without symptoms, an abnormality on the dipstick is found in some, usually without a serious cause.
NHG guideline on urinary tract infections; NHG guideline on chronic kidney damage
Get tested
Ketones: test panels
Ketones is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.
Evidence
Sources
This explanation is based on Dutch guidelines and independent information. It is general information, not a diagnosis. Discuss an abnormal result with your GP.
More about risks and resultsMore explanations
Other tests: Urine tests
- Bilirubin
- Erythrocytes and free hemoglobin
- Glucose
- Leukocytes
- Nitrite
- pH
- Protein
- Specific gravity
- Urobilinogen