Question

Hypokalemia is caused by the following EXCEPT

• A. Cushing's syndrome
• B. Conn's syndrome
• C. Bartter's syndrome
• D. Addison's disease

Hint:

Three of these have too much mineralocorticoid effect; one has too little.

Answer 1

The Correct Option is D

This question asks which of four conditions is the exception that does not cause hypokalemia.

1. Cushing's syndrome: Very high cortisol levels act like excess mineralocorticoid on the kidney, increasing potassium loss and causing hypokalemia.
2. Conn's syndrome: Excess aldosterone in this condition directly drives potassium excretion, making hypokalemia a hallmark feature.
3. Bartter's syndrome: This tubular defect causes salt wasting and secondary hyperaldosteronism, leading to significant hypokalemia.
4. Addison's disease: This is caused by aldosterone deficiency, not excess, so the kidney retains potassium instead of excreting it, causing hyperkalemia rather than hypokalemia.

Since Addison's disease works through hormone deficiency rather than excess, it produces the opposite electrolyte change and is the correct exception.

Let's summarize:

• Cushing's, Conn's, and Bartter's syndromes all increase potassium loss through excess mineralocorticoid effect.
• Addison's disease has too little aldosterone, causing hyperkalemia instead.

So the exception is Addison's disease.