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Ketone Testing: About Your Child's Test

What is it?

A ketone test checks for ketones in your child's blood or urine. Ketones are made when the body breaks down fat for energy instead of using sugar. This can happen when children with diabetes are ill or don't get enough insulin.

Why is this test done?

Measuring your child's ketones is recommended whenever your child has symptoms of illness, such as nausea, vomiting, or belly pain. These symptoms are similar to symptoms of high blood sugar and may mean that your child has diabetic ketoacidosis. This condition is very serious and needs immediate treatment.

How do you prepare for the test?

In general, your child doesn't need to prepare before having this test. Your doctor may give you some specific instructions.

How is the test done?

Blood test in a doctor's office or hospital

A health professional uses a needle to take a blood sample, usually from an arm.

Blood test at home

Some home blood sugar meters can also measure blood ketones. You use the same finger-prick method that you use to measure your child's blood sugar.

Home urine test

  • Collect a sample of urine in a clean container.
  • Follow the manufacturer's directions on the bottle of test strips or tablets.

What do the results of the test mean?

  • With the home urine test, if either the test strip changes colour or the urine changes colour when the tablet is dropped into the sample, ketones are present in your child's urine sample. The test results are read as negative to 1+ to 4+, or small to large.
  • Blood ketone tests using a meter display the result on the monitor. Your doctor can tell you what ketone range is high for your child (for example 0.6 mmol/L or higher).
  • Talk to your doctor ahead of time about what to do when your child's ketone levels are high.

How long does the test take?

The test will take a few minutes.

What happens after the test?

Your child can go back to his or her usual activities right away.

When should you call for help?

Watch closely for changes in your child's health, and be sure to contact your doctor or nurse advice line if:

  • Your child has moderate or large amounts of ketones in the urine or a high level of blood ketones (for example more than 0.6 mmol/L).

Follow-up care is a key part of your child's treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if your child is having problems. It's also a good idea to keep a list of the medicines your child takes. Ask your doctor when you can expect to have your child's test results.

Where can you learn more?

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