What are the key diagnostic criteria for diabetic ketoacidosis (DKA) in adults?

The key diagnostic criteria for diabetic ketoacidosis (DKA) in adults typically involve a triad of findings: hyperglycaemia, ketosis, and metabolic acidosis Dhatariya et al. 2020Rodriguez Alvarez et al. 2025. Specifically, DKA is diagnosed in adults based on a plasma glucose level greater than 11 mmol/litre, the presence of ketosis, and acidosis NICE CKS,NICE CKS. Ketosis can be indicated by moderate ketonuria (2+ on urine dipstick) or ketonaemia (1.5–2.9 mmol/L) NICE CKS,NICE CKS. For a definitive diagnosis, blood beta-hydroxybutyrate levels above 3 mmol/litre or significant ketonuria (2+ or more on a standard strip) are indicative of ketosis [1, Dhatariya et al., 2020]. Metabolic acidosis is characterised by a blood pH below 7.3 or plasma bicarbonate below 15 mmol/litre [1, Dhatariya et al., 2020]. While the NICE guideline primarily details DKA in children and young people, the principles of diagnosis, including hyperglycaemia and ketosis, are considered for adults in clinical practice NICE NG18,NICE CKS,NICE CKS. Capillary blood ketone testing should be considered in adults with suspected DKA or uncontrolled diabetes with positive urine ketones NICE NG17.