Diabetic ketoacidosis is said to be present if:
**Core Concept**
Diabetic ketoacidosis (DKA) is a serious complication of diabetes characterized by hyperglycemia, metabolic acidosis, and ketosis. It occurs when the body produces high levels of ketones, acidic substances that can poison the body.
**Why the Correct Answer is Right**
DKA is diagnosed when there is a combination of hyperglycemia (blood glucose ≥ 250 mg/dL), metabolic acidosis (pH < 7.3), and ketosis (elevated levels of ketone bodies in the blood). This condition is a result of insulin deficiency or resistance, which leads to an increase in glucose levels in the blood. The body tries to compensate for the lack of glucose by breaking down fat for energy, resulting in the production of ketones.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because a blood glucose level of ≥ 250 mg/dL is a necessary but not sufficient criterion for diagnosing DKA. Patients with DKA may have lower glucose levels, especially if they are receiving insulin or other treatments.
* **Option B:** This option is incorrect because an elevated anion gap is a characteristic of metabolic acidosis, but it is not a specific criterion for diagnosing DKA. Other conditions, such as lactic acidosis or renal failure, can also cause an elevated anion gap.
* **Option C:** This option is incorrect because elevated blood ketone levels are a hallmark of DKA, but they are not the only factor in the diagnosis. Patients with DKA may have other symptoms or laboratory abnormalities, such as hyperglycemia or metabolic acidosis.
**Clinical Pearl / High-Yield Fact**
Remember that DKA is a medical emergency that requires prompt recognition and treatment. The mnemonic "CET" can help you remember the key components of DKA: **C** (Catabolic state), **E** (Elevated glucose), and **T** (Type 1 diabetes or insulin deficiency).
**Correct Answer: C. Elevated blood ketone levels.