## **Core Concept**
Metabolic alkalosis is a condition characterized by an increase in blood pH due to an excess of bicarbonate ions. When associated with hypertension, it often points towards conditions that involve excessive mineralocorticoid activity or other mechanisms leading to sodium retention and volume expansion.

## **Why the Correct Answer is Right**
The conditions associated with metabolic alkalosis and hypertension typically involve excessive activity of mineralocorticoids (like aldosterone) or substances with similar effects, leading to sodium retention, volume expansion, and consequently, hypertension. The correct answer, Cushing's syndrome, is indeed associated with metabolic alkalosis and hypertension due to the effects of excess cortisol, which can mimic mineralocorticoids.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Primary aldosteronism (Conn's syndrome) is a classic cause of metabolic alkalosis with hypertension. Aldosterone promotes sodium retention and potassium excretion, leading to volume expansion and hypertension, along with hypokalemia that contributes to metabolic alkalosis.
- **Option B:** Liddle's syndrome is another condition that presents with metabolic alkalosis and hypertension. It is caused by mutations in the genes encoding for the epithelial sodium channel (ENaC), leading to unregulated sodium absorption and potassium secretion, similar to the effects of excessive aldosterone but without the hormonal elevation.
- **Option D:** The syndrome of apparent mineralocorticoid excess (AME) is a rare condition that also presents with metabolic alkalosis and hypertension. It is due to a deficiency of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), the enzyme responsible for converting cortisol to cortisone. Cortisol then acts on the mineralocorticoid receptor, mimicking aldosterone.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is to remember that in evaluating causes of metabolic alkalosis with hypertension, one should consider conditions that lead to excessive mineralocorticoid activity or effect, such as primary aldosteronism, Liddle's syndrome, and Cushing's syndrome. The differentiation among these conditions often requires specific biochemical and sometimes genetic testing.

## **Correct Answer:** C. Cushing's syndrome is less directly associated with the typical profile of mineralocorticoid excess (like primary aldosteronism) but can cause metabolic alkalosis and hypertension; however, among the given options and based on typical associations and mechanisms, **Correct Answer: C**.