Which statement best differentiates diabetic ketoacidosis (DKA) from lactic acidosis in terms ketone bodies and insulin deficiency?

• A. DKA features ketosis with ketone bodies due to insulin deficiency; lactic acidosis is due to lactate elevation often with sepsis or hypoperfusion and may have little ketosis.
• B. Lactic acidosis always involves increased ketone production.
• C. DKA occurs without any ketosis or ketones.
• D. Lactic acidosis is caused by low lactate levels.

Answer: (A)

The key idea is that diabetic ketoacidosis is driven by insulin deficiency leading to increased fat breakdown and ketone production, so ketosis is a hallmark, whereas lactic acidosis is caused by elevated lactate from impaired oxygen delivery or utilization and does not rely on ketone buildup.

In DKA, lack of insulin lets adipose tissue release free fatty acids, which the liver rapidly converts into ketone bodies. Those ketones accumulate and cause metabolic acidosis with a strong ketosis signal. In lactic acidosis, the acidemia comes from excess lactate produced during anaerobic metabolism (often due to sepsis or poor perfusion); ketone production is not the defining feature, and ketosis is typically minimal or not a major part of the picture.

Thus the statement describing ketosis with insulin deficiency in DKA and lactate-driven acidosis with little ketosis best differentiates the two conditions. The other options are inconsistent with the typical mechanisms: lactic acidosis does not always involve ketone production, DKA inherently involves ketosis, and lactic acidosis is not caused by low lactate.