Which pattern of laboratory findings best describes diabetic ketoacidosis?

• A. Hyperkalemia with nonketotic metabolic acidosis
• B. Metabolic acidosis with normal anion gap and no ketones
• C. Anion gap metabolic acidosis with ketonemia/ketonuria and hyperglycemia
• D. Metabolic alkalosis with ketosis

Answer: (C)

In diabetic ketoacidosis the labs reveal an anion-gap metabolic acidosis caused by accumulating ketoacids, together with ketonemia/ketonuria and hyperglycemia. The lack of insulin triggers lipolysis and ketogenesis, producing ketoacids (beta-hydroxybutyrate and acetoacetate) that raise the anion gap, while high glucose reflects impaired insulin action and increased hepatic glucose production. Dehydration from osmotic diuresis and electrolyte losses often accompany this picture, and potassium may be elevated early on despite a total body potassium deficit.

This pattern fits best because it combines anion-gap acidosis with ketosis and marked hyperglycemia—hallmarks of DKA. The other options describe either nonketotic acidosis, a normal anion gap, or an alkalosis, none of which align with the typical DKA profile.