Diabetic Ketoacidosis (DKA)

Diabetic Ketoacidosis (DKA)

What is Diabetic Ketoacidosis (DKA)?

Diabetic Ketoacidosis (DKA) is a life-threatening condition characterised by high blood sugar levels, increased ketone (acids) production, and loss of body water that occurs when there is insufficient insulin in the body. Diabetic Ketoacidosis is a very treatable condition if recognised. It can affect both those with type 1 and type 2 diabetes, however it is more common in type 1 diabetics.     

What causes Diabetic Ketoacidosis? (DKA)

Diabetic ketoacidosis is caused by insufficient levels of insulin circulating in the body. Insulin is a hormone produced by the pancreas (an organ in the abdomen) after ingestion of food. It signals to the body that there is energy taken in and acts to normalise blood sugar levels. One of the effects of insulin is to stop the body producing molecules known as ketones. During fasting or starvation, the body produces ketones to replace sugar and they can be used as an energy source. However, they are normally produced in relatively small quantities and in a well hydrated person do not cause the blood to become acidic. During diabetic ketoacidosis, the absence of insulin means that the blood sugar levels and ketones are very high. The body loses water due to the high blood sugar levels and in the presence of dehydration, the ketones make the blood acidic. This can affect the function of the organs and ultimately cause death.

Key risk factors include states in which there is insufficient insulin produced by the body:

• Not taking insulin as prescribed (due to insufficient supplies or patient choice)
• Undiagnosed and untreated type 1 diabetes

Furthermore, risk factors for diabetic ketoacidosis includes anything that increases the insulin demands or overall stress placed on the body (or the total volume of insulin required).

This includes: 

• Infections (such as chest infections and urine infections)
• Viral illnesses such as gastroenteritis (winter vomiting bug)
• Traumatic injuries
• Recreational drug use (such as cocaine)
• Pregnancy
• Undergoing a recent operation

How is diabetic ketoacidosis diagnosed?

Diabetic ketoacidosis is diagnosed in hospital, and it is generally associated with another illness such as an infection. The key investigations are blood tests and then further assessment to assess for precipitating causes.

For example, diagnosing diabetic ketoacidosis generally requires three key parameters:

• Ketonaemia (ketones in the blood) or significant ketonuria (more than 2 + on of ketones in the urine)
• Blood glucose over 11 mmol ⁄ l or known diabetes mellitus
• Venous bicarbonate below 15 mmol ⁄ l and ⁄ or venous pH less than 7.3 (meaning the blood is acidic)   

Further investigations for other precipitating causes can include:

• Chest x-ray to assess for a chest infection
• Urine test to assess for urine infection
• Blood cultures to assess for a blood infection
• Blood testing to assess for signs of infection or inflammation    

How common is it?

Overall, the rate at which people develop diabetic ketoacidosis has remained largely unchanged with around 13 per 100,000 people developing it each year. It seems to have become less common in younger people with a slight increase in older type 2 diabetics. Around 1 in 10 affected had a diagnosis of type 2 diabetes and hence it predominantly affects those with type 1 diabetes.