Diabetic ketoacidosis - Causes of diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is a complication of diabetes that can occur if the body starts to run out of insulin (the hormone that regulates blood sugar).

It can be caused by a number of underlying problems including an infection, a missed insulin injection or undiagnosed diabetes (see below). In some cases, it may also be triggered by another illness, such as a stroke or a heart attack.

Insulin deficiency

A lack of insulin can send the body’s metabolism into a destructive downward spiral. The metabolism is the complex process of chemical reactions the body uses to break down food into energy.

Insulin enables the body to use blood sugar (glucose). If there is a lack of insulin, or if it can't be used properly, the body will break down fat instead.

The breakdown of fat releases acidic chemicals (ketones). High levels of glucose and ketones make you pass large amounts of urine. This can lead to severe dehydration.

Therefore, there are a number of interlinked problems with the body’s metabolism that can quickly make a person very ill. These are:

high blood glucose levels (hyperglycaemia) due to the lack of insulin
high levels of acid in the blood due to a build-up of ketones
falling levels of the mineral, potassium, which is essential to good health - vomiting and treatment for diabetic ketoacidosis can cause a decrease in potassium levels (hypokalemia)

Common triggers

The three most common triggers for diabetic ketoacidosis are:

an underlying infection
missed insulin treatment
the onset of previously undiagnosed diabetes (usually type 1 diabetes)

These are discussed in more detail below.

Infection

The body’s response to infection is to produce more glucose. Too much glucose can make insulin treatment ineffective, triggering diabetic ketoacidosis.

The most common infections are:

urinary tract infection (UTI) - including bladder and kidney infections
pneumonia - a lung infection
gastroenteritis - an infection of the digestive system
flu (influenza)

Missed treatment

There are a number of reasons why someone with diabetes may miss their recommended treatment including:

psychological stress - often a common cause in teenagers with type 1 diabetes
frequent injections disrupting daily activity
finding frequent injections painful
concern about weight gain

Undiagnosed diabetes

The symptoms of type 1 diabetes often develop quickly, and a delay in diagnosing the condition can sometimes progress to diabetic ketoacidosis.

However, this only occurs in a small number of people with type 1 diabetes which suggests they have a particularly severe form of the condition compared to other people.

Other triggers

Less common triggers for diabetic ketoacidosis include:

using illegal drugs, such as cocaine, ecstasy and ketamine
binge drinking - drinking lots of alcohol over a short period of time or drinking to get drunk
other illnesses, such as a stroke or heart attack
a damaged or malfunctioning insulin injector or pump