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Diabetic Ketoacidosis


Erika F. Brutsaert

, MD, New York Medical College

Last full review/revision Sep 2020| Content last modified Sep 2020

Diabetic ketoacidosis is an acute complication of diabetes that occurs mostly in type 1 diabetes mellitus.

  • Symptoms of diabetic ketoacidosis include nausea, vomiting, abdominal pain, and a characteristic fruity odor on the breath.
  • Diabetic ketoacidosis is diagnosed by blood tests that show high levels of glucose, ketones, and acid.
  • Treatment of diabetic ketoacidosis involves intravenous fluid replacement and insulin.
  • Without treatment, diabetic ketoacidosis can progress to coma and death.

(See also Diabetes Mellitus.)

There are two types of diabetes mellitus, type 1 and type 2. In both types, the amount of sugar (glucose) in the blood is elevated.

Glucose is one of the body's main fuels. Insulin, a hormone produced by the pancreas, helps glucose move from the blood into the cells. Once glucose is inside the cells, it is either converted to energy or stored as fat or glycogen until it is needed.

When there is not enough insulin, most cells cannot use the glucose that is in the blood. Because cells still need energy to survive, they switch to a back-up mechanism to obtain energy. Fat cells begin breaking down, producing compounds called ketones. Ketones provide some energy to cells but also make the blood too acidic (ketoacidosis).

Ketoacidosis that occurs in people with diabetes is called diabetic ketoacidosis. Diabetic ketoacidosis occurs mainly in people who have type 1 diabetes because their body produces little or no insulin. However, rarely, some people with type 2 diabetes develop ketoacidosis. People who abuse alcohol also can develop ketoacidosis (alcoholic ketoacidosis). Unlike in diabetic ketoacidosis, blood glucose levels are usually only mildly elevated.

Causes of Diabetic Ketoacidosis

Diabetic ketoacidosis is sometimes the first sign that people (usually children—see also Diabetic ketoacidosis (DKA)) have developed diabetes. In people who know they have diabetes, diabetic ketoacidosis can occur for two main reasons:

  • People stop taking their insulin
  • An illness stresses the body

An illness usually increases the body's need for energy. Thus, when people become ill, they often need more insulin to move extra glucose into their cells. If people do not take extra insulin when they are ill, they can develop diabetic ketoacidosis.

Common illnesses that can trigger diabetic ketoacidosis include

Rarely, some drugs, especially the sodium-glucose co-transporter-2 (SGLT-2) inhibitors, can cause diabetic ketoacidosis, even in people with type 2 diabetes.

Some people with type 2 diabetes are prone to develop ketoacidosis. This type of diabetes is called ketosis-prone diabetes, but is often referred to as Flatbush diabetes. This type of diabetes is an unusual variant that is more likely to occur in obese people and in people of African ancestry.

Symptoms of Diabetic Ketoacidosis

The initial symptoms of diabetic ketoacidosis include excessive thirst and urination, weight loss, nausea, vomiting, fatigue, and—particularly in children—abdominal pain. Breathing tends to become deep and rapid as the body attempts to correct the blood’s acidity. The breath has a fruity odor similar to nail polish remover because of the smell of the ketones escaping into the breath. Without treatment, diabetic ketoacidosis can progress to coma and death (especially in children).

Diagnosis of Diabetic Ketoacidosis

  • Blood and urine tests to determine levels of ketones and acid

Doctors diagnose diabetic ketoacidosis by measuring the level of ketones and acid in the blood and urine. People with diabetic ketoacidosis also have high blood glucose levels, but people may have high glucose levels without having diabetic ketoacidosis (see Hyperosmolar, Hyperglycemic State).

Doctors typically also do tests, such as a chest x-ray and urine analysis, to look for an underlying infection and electrocardiography (ECG) to look for a heart attack.

Treatment of Diabetic Ketoacidosis

  • Intravenous fluids and electrolytes
  • Intravenous insulin

Diabetic ketoacidosis is a medical emergency. Hospitalization, usually in an intensive care unit, may be necessary. Large amounts of fluids are given intravenously along with electrolytes, such as sodium, potassium, chloride, and sometimes phosphate, to replace those fluids and electrolytes lost through excessive urination.

Insulin is generally given intravenously so that it works quickly and the dose can be adjusted frequently.

Blood levels of glucose, ketones, and electrolytes are measured every few hours. Doctors also measure the blood’s acid level. Sometimes, additional treatments are needed to correct a high acid level. However, controlling the levels of glucose in the blood with insulin and replacing electrolytes usually allow the body to restore the normal acid-base balance.

More Information about Diabetic Ketoacidosis

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of the resources.

  • American Diabetes Association: Comprehensive information on diabetes, including resources for living with diabetes
  • JDRF (previously called Juvenile Diabetes Research Foundation): General information on type 1 diabetes mellitus
  • National Institute of Diabetes and Digestive and Kidney Diseases: General information on diabetes, including on the latest research and community outreach program

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