Which statement accurately describes the primary mechanism leading to diabetic coma?

• A. Overhydration and dilution of electrolytes
• B. Ketone accumulation from fat breakdown causing acidosis
• C. Excessive insulin causing rapid hypoglycemia
• D. Chronic high blood sugar causing dehydration only

Answer: (B)

When insulin is lacking, the body can’t use glucose inside its cells, so it starts breaking down fat for energy. This process produces ketone bodies (like acetoacetate and beta-hydroxybutyrate). These accumulate and create a metabolic acidosis with a high anion gap. That acid buildup, along with dehydration from high blood glucose, can seriously depress brain function and lead to a diabetic coma. So the key mechanism is ketone production from fat breakdown causing acidosis.

Overhydration and electrolyte dilution isn’t the driving factor, because diabetic dehydration from osmotic diuresis is the problem, not excess fluids. While too much insulin can cause hypoglycemia and coma, that’s a different scenario than the typical diabetic coma driven by ketoacidosis. Chronic high glucose causing dehydration alone doesn’t explain the coma without the acid buildup from ketones.