A 40-year-old woman has experienced increasingly frequent episodes of weakness accompanied by numbness and tingling in her hands and feet for the past year. On examination, her blood pressure is 168/112 mm Hg. Laboratory studies show sodium, 142 mmol/L; potassium, 2.9 mmol/L; chloride, 104 mmol/L; HCO3-, 28 mmol/L; and glucose, 74 mg/dL. Her plasma renin activity is low. Which of the following radiologic findings is most likely to be present in this woman?

**Core Concept**
The patient's symptoms and laboratory findings suggest primary aldosteronism, a condition characterized by excess production of aldosterone, a mineralocorticoid hormone produced by the adrenal glands. Aldosterone promotes sodium retention and potassium excretion, leading to hypertension and hypokalemia.

**Why the Correct Answer is Right**
The patient's low plasma renin activity is consistent with primary aldosteronism, as aldosterone suppresses renin release. The patient's hypertension, hypokalemia, and metabolic alkalosis are also characteristic of this condition. Aldosterone excess leads to increased sodium reabsorption in the collecting ducts of the kidneys, resulting in hypertension and hypokalemia.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not describe a typical radiologic finding associated with primary aldosteronism. The condition is often caused by an aldosterone-producing adenoma in the adrenal gland, but this is not typically visible on a plain radiograph.

**Option B:** This option is incorrect because it is not a common radiologic finding in primary aldosteronism. While some patients may have bilateral adrenal hyperplasia, this is not the most likely cause of the patient's symptoms.

**Option C:** This option is incorrect because it is not a specific radiologic finding associated with primary aldosteronism. The patient's symptoms and laboratory findings are more consistent with primary aldosteronism than with Cushing's syndrome.

**Clinical Pearl / High-Yield Fact**
In primary aldosteronism, the patient often has a suppressed renin-angiotensin-aldosterone system (RAAS), which can be used as a diagnostic clue.

**Correct Answer:** C.

✓ Correct Answer: A. Adrenal nodular enlargement