Diabetic ketoacidosis (DKA)

Diabetic ketoacidosis develops when there is not enough insulin for the body to use glucose. Blood sugar rises, and, unable to get energy from glucose, the body breaks down fat instead, producing acids called ketones that build up and turn the blood dangerously acidic. It is most common in type 1 diabetes, and can be the first sign of it, but also occurs in type 2 under stress. Common triggers are infection or other illness, missed or insufficient insulin, and sometimes a new diagnosis of diabetes. It develops over hours to a day or two, causing very high thirst and urination, nausea and vomiting, abdominal pain, tiredness, a characteristic deep and rapid breathing (as the body tries to blow off acid), a fruity smell on the breath, and progressive drowsiness and confusion. Blood tests show the triad: high glucose, high ketones and an acidic blood with a low bicarbonate and a raised anion gap. It is a medical emergency treated urgently in hospital with insulin, fluids and careful replacement of salts (especially potassium). Recognised and treated promptly, people recover well; delayed, it can be fatal.

• Glucose — high (though occasionally only moderately raised).
• Blood ketones (beta-hydroxybutyrate) — high; the key confirming finding.
• Bicarbonate — low, and blood pH acidic (metabolic acidosis).
• Anion gap — raised.
• Potassium — needs close monitoring; can be high initially but falls dangerously with treatment.
• Kidney function and blood count — assess dehydration and any infection trigger.

• Excessive thirst and passing large amounts of urine
• Nausea and vomiting
• Abdominal pain
• Tiredness and weakness
• Deep, rapid breathing
• A fruity or acetone smell on the breath
• Drowsiness, confusion, and, if untreated, reduced consciousness
• Often a preceding illness or missed insulin