Which of the following condition is not associated with an increased anion-gap type of metabolic acidosis?
**Core Concept**
The anion-gap type of metabolic acidosis is characterized by an increase in the anion gap due to the accumulation of unmeasured anions in the blood. This condition occurs when there is a failure of the kidneys to excrete organic acids or when there is an increase in the production of acidic substances.
**Why the Correct Answer is Right**
The anion-gap type of metabolic acidosis is typically associated with conditions that lead to the accumulation of unmeasured anions, such as lactic acidosis, diabetic ketoacidosis, and renal failure. In these conditions, the kidneys are unable to effectively excrete organic acids, leading to an increase in the anion gap. On the other hand, conditions like diabetic ketoacidosis are not typically associated with an increased anion-gap type of metabolic acidosis, as the metabolic acidosis in this condition is largely due to the accumulation of ketones, which are measured anions.
**Why Each Wrong Option is Incorrect**
* **Option A:** Lactic acidosis is a classic example of an increased anion-gap type of metabolic acidosis, as it is caused by the accumulation of lactic acid, an unmeasured anion.
* **Option B:** Diabetic ketoacidosis is also associated with an increased anion-gap type of metabolic acidosis, as it is caused by the accumulation of ketones, which are unmeasured anions.
* **Option C:** Renal failure can lead to an increased anion-gap type of metabolic acidosis due to the kidneys' inability to excrete organic acids.
**Clinical Pearl / High-Yield Fact**
The anion gap can be calculated using the following formula: Anion Gap = Sodium - (Chloride + Bicarbonate). A normal anion gap is typically less than 12 mmol/L.
**Correct Answer:** D.