A Breath Test for Ketoacidosis

Written by Thomas G. Ciccone
Reviewed by J. Michael Gonzalez-Campoy, MD, PhD, FACE

Diabetic ketoacidosis is a preventable acute complication of type 1 diabetes (DM).  It develops rapidly upon interruption of insulin therapy, or when conditions develop that do not allow insulin to work (for example, acute illness).

When someone with diabetes doesn't have enough insulin to burn glucose as fuel, their body can start breaking down fat instead. Ketones start building up in the bloodstream. Ketones are acid, and their accumulation in the blood may lead to diabetic ketoacidosis.

Diabetic ketoacidosis may be lethal even in this day and age. Children, who depend on parental management of diabetes, are especially susceptible to diabetic ketoacidosis, but anyone with type 1 DM may get it.

Home testing for ketones is available, however they currently require either a blood or urine sample. These tests differ from the standard blood sugar tests (fingerstick glucose test for A1c levels). Every patient with type 1 DM (or caregiver) is instructed to check for ketones whenever:

• The child does not feel well
• They become dehydrated
• They have an interruption of insulin therapy
• Their blood glucose testing reads high.

For more information on how to avoid diabetic ketoacidosis.  

Researchers in England have developed a potentially easier way to monitor these ketone levels, and curiously enough, the trick may lie in a person's breath.

Breath Test Detects Acetone

In a recent study at Oxford Children's Hospital,1 researchers tested more than 100 patients with type 1 diabetes between the ages of 7 to 18 years old, measuring gases in their breath and ketone levels in their blood. Researchers found that one gas in particular—acetone— seemed to predict ketone levels well. A new way to monitor patients with Type 1 DM for ketones is down the road.

Typically, doctors find out how much ketone is in the blood by measuring the capillary levels of β hydroxybutyrate (BHB).2 When first diagnosed with Type 1 diabetes, children usually show high BHB levels.3 High BHB levels are associated with diabetic ketoacidosis, which may be lethal.

"Breath acetone on its own does not seem to be a good predictor of blood glucose in this cohort," said Gus Hancock, PhD, Professor of Chemistry at the University of Oxford, a co-author of the study. "However, the statistically significant relationship that we found between blood ketones and breath acetone is something that we are pursuing."

More Research Needed

The researchers expect more studies to be done, especially with children that have diabetic ketoacidosis, so this relationship between acetone in the breath and ketones in the blood can be more fully understood. An exciting new way to monitor for diabetic ketoacidosis may come out of this.

Dr. Hancock and his colleagues are already working on a prototype of a convenient, hand-held device that could monitor breath acetone. Being manufactured by Oxford Medical Diagnostics, the team hopes to start testing the device in 2015, Dr. Hancock said.

"The prototype device works by spectroscopy inside an optical cavity (“Cavity enhanced absorption spectroscopy”) which allows high sensitivity and high selectivity for breath acetone," Dr. Hancock described. "The aim here is to see if elevated breath acetone would be a good indicator of the onset of diabetic ketoacidosis."

Diabetes Rates Rising Among Children

Diabetes cases are rising throughout the US; in the last decade alone, a study found there to be 21% more adolescents with Type 1 diabetes.4 Monitoring Type 1 diabetes in children is becoming a prevalent challenge for doctors.

DiabeticLifestyle Editorial Board Member Amy Hess-Fischl commented on how such a device could be useful for patients. "At this point, noninvasive is an attractive option for people with diabetes," she said, "For small children, it is hard enough to get the information necessary to treat them appropriately (urine ketone testing with toddlers is a nightmare) so an alternate method to make it easy to identify ketones would be welcome."

Also commenting on the study finding, J. Michael Gonzalez-Campoy, MD, PhD, FACE, noted “The current study offers the promise of real-time testing for the development of ketones in a non-invasive manner.  This will help bring about earlier intervention in diabetic ketoacidosis.” 

Breath tests may not only be convenient, but lifesaving, as well. "Urine ketones tell us about the ketones generated hours ago. Blood ketones tell us what is happening now – the same for exhaled gases," added Ms Hess Fischl.

However, urine ketone testing is still very popular because it's cheap, while blood ketone tests typically cost around 10 dollars a strip. Since insurance companies may not cover these tests, it can cause a fiscal problem in families who are trying to monitor their child's ketone levels.

Monitoring ketone levels is most important when one is sick or has a blood glucose level over 240 mg/dL.

"So, in order for this new test to be used and benefit families and people with type 1 diabetes, it cannot be cost-prohibitive," she concluded.

This recent research was funded by the Department of Chemistry of the University of Oxford. Gus Hancock is the Chief Scientific Officer and non-Executive Director of Oxford Medical Diagnostics, Rob Peverall is the science director at Oxford Medical Diagnostics, and Tom P J Blaikie, David Taylor, and Graham Richmond are employees of Oxford Medical Diagnostics. There were no other conflicts of interest reported.

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How to Avoid Diabetic Ketoacidosis