Question

Consider the following: 1. Generalised oedema 2. Hypertension 3. Hypokalemia. Which of these is/are present in Conn's syndrome?

• A. 1 and 2
• B. 2 and 3
• C. 3 only
• D. 1, 2 and 3

Hint:

Recall the one classic feature of secondary hyperaldosteronism states that Conn's syndrome does NOT show, thanks to aldosterone escape.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
Conn's syndrome is primary hyperaldosteronism, usually from an aldosterone-secreting adrenal adenoma. The question asks which of generalised oedema, hypertension, and hypokalemia are actually seen in this condition.

Step 2: Key Concept or Approach:
Excess aldosterone acts on the renal distal tubule to increase sodium reabsorption in exchange for potassium and hydrogen ion excretion. The sodium retention expands plasma volume and raises blood pressure, giving hypertension, while continued potassium loss produces hypokalemia. However, once several litres of extra fluid have been retained, the kidney escapes further sodium retention through a pressure-natriuresis mechanism (mediated partly by atrial natriuretic peptide), so fluid does not go on accumulating in the tissues - this is why Conn's syndrome does not cause generalised oedema, unlike secondary hyperaldosteronism states with low effective circulating volume.

Step 3: Working Through the Options:
"1 and 2" and "1, 2 and 3" both wrongly include generalised oedema. "3 only" misses the hypertension that is a defining feature of the syndrome. "2 and 3" - hypertension and hypokalemia - matches the actual clinical picture.

Step 4: Conclusion:
The correct answer is "2 and 3": Conn's syndrome presents with hypertension and hypokalemia, but classically without generalised oedema because of aldosterone escape.