Parathyroid: differential of hypercalcaemia: practice question

A General Surgery question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

General Surgery · Parathyroid: differential of hypercalcaemia

Sample item

A 35-year-old woman has asymptomatic serum calcium 11.0 mg/dL, normal PTH, and a 24-hour urinary calcium to creatinine clearance ratio below 0.01. Her father and sister also have mild hypercalcaemia. What is the diagnosis and management?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

D. Familial hypocalciuric hypercalcaemia, with no surgery

Familial hypocalciuric hypercalcaemia results from an inactivating mutation of the calcium-sensing receptor, so the kidney reabsorbs calcium avidly despite hypercalcaemia. A calcium to creatinine clearance ratio under 0.01 differentiates it from primary hyperparathyroidism. It is benign, and parathyroidectomy does not correct the biochemistry.

Option by option

  • A. Sporadic parathyroid adenoma, for parathyroidectomy

    In primary hyperparathyroidism the clearance ratio is usually above 0.02 and surgery cures it, which is not the case here.

  • B. Humoral hypercalcaemia of malignancy, for oncology work-up

    Malignancy produces suppressed PTH and a marked clinical illness rather than a stable familial pattern.

  • C. Vitamin D intoxication, for steroids

    Vitamin D toxicity has a suppressed PTH and high urinary calcium, and does not run in families.

  • D. Familial hypocalciuric hypercalcaemia, with no surgery (correct)

    Correct. Low urinary calcium with a family history and a normal PTH point to FHH, which is benign.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More General Surgery questions

Questions about this General Surgery question

What is the answer to this General Surgery question?

The best answer is D, Familial hypocalciuric hypercalcaemia, with no surgery. Familial hypocalciuric hypercalcaemia results from an inactivating mutation of the calcium-sensing receptor, so the kidney reabsorbs calcium avidly despite hypercalcaemia.

Why is "Sporadic parathyroid adenoma, for parathyroidectomy" not the answer?

In primary hyperparathyroidism the clearance ratio is usually above 0.02 and surgery cures it, which is not the case here.

Why is "Humoral hypercalcaemia of malignancy, for oncology work-up" not the answer?

Malignancy produces suppressed PTH and a marked clinical illness rather than a stable familial pattern.

Why is "Vitamin D intoxication, for steroids" not the answer?

Vitamin D toxicity has a suppressed PTH and high urinary calcium, and does not run in families.

What concept does this question test?

It tests Parathyroid: differential of hypercalcaemia in General Surgery. A calcium to creatinine clearance ratio under 0.01 differentiates it from primary hyperparathyroidism. It is benign, and parathyroidectomy does not correct the biochemistry.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Parathyroid: differential of hypercalcaemia?

Learn classic signs and eponyms alongside what they diagnose. Then use the flashcards and the other General Surgery questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.