Urine and Serum Ketone Testing

Insulin normally allows glucose to move from the bloodstream into cells for energy. When insulin is absent or insufficient, the body shifts toward fatty-acid breakdown. The liver converts fatty acids into ketones: beta-hydroxybutyrate (β-HB), acetoacetate, and acetone. This is an emergency pattern in a person with diabetes because ketone production can outpace the body’s ability to buffer acid. β-HB is the predominant ketone in diabetic ketoacidosis (DKA), which is why blood β-HB testing gives a more useful picture of current ketone burden than urine testing. A ketone result answers a focused question: is the person lacking enough effective insulin and moving toward ketoacidosis? It does not replace the rest of the assessment. Breathing pattern, mental status, ability to drink, glucose trend, electrolyte results, and acid-base status determine how dangerous the situation has become.