I recently found myself in the hospital with a diagnosis of diabetic ketoacidosis (DKA). It was a complete shock. Just an awareness of what DKA is, how serious it can be, and what its symptoms are could help keep someone from getting a costly hospital bill and, more important, a potentially deadly diagnosis.
Meghan Hardy, Manhattan, Kan.

Paris Roach, MD, responds: It's essential for everyone with type 1 diabetes to know the risk factors for and the symptoms of DKA and how to prevent it. (DKA can develop in people with type 2 diabetes, but it's less common.) The two main causes of DKA are interruption of insulin treatment (missing insulin injections or failure of an insulin pump system) and severe illness, such as the flu with fever or even a heart attack or stroke.

Insulin controls the production of ketones, the substances that build up in the bloodstream and cause DKA, so if someone with type 1 diabetes stops taking insulin, DKA can result. During an illness, the body produces stress hormones, which counteract insulin action to such an extent that DKA can develop. High blood glucose levels result, leading to excessive urination and dehydration, which in turn push blood glucose and ketones to even higher levels. Some people incorrectly assume that if they're sick and not eating, they shouldn't take insulin, but this will result in rapid development of DKA. That's why it's important to work with your care provider early during an illness to determine the best way to avoid interruption of insulin treatment. Dehydration that occurs due to vomiting, inability to eat and drink, and high glucose and ketone levels can also contribute to rapid worsening of DKA. 

The symptoms of DKA include nausea, vomiting, abdominal pain, dry mouth, thirst, and excessive urination. In advanced stages of DKA, a rapid, deep breathing pattern develops, and the breath takes on a fruity odor. A decreased level of consciousness is particularly ominous and should prompt a call for emergency medical services.
The best way to prevent DKA is to check your urine ketones when your blood glucose is persistently high (greater than 250 mg/dl) and not responding normally to additional insulin, especially if you're sick. Ketone test kits are available at pharmacies. DKA can develop rapidly, so it's very important to check ketones early, to seek professional medical advice, and to go for emergency care promptly if your blood glucose and ketone levels are not responding to treatment. If you're persistently nauseated or vomiting and can't drink fluids to stay hydrated, you should call your care provider immediately. 

All people with type 1 diabetes should have a reliable means for measuring urine ketones on hand. When in doubt, check your ketones—it's easy and inexpensive, and it provides the critical information needed to prevent DKA.