Endocrine physiology: growth hormone: practice question

A Physiology 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.

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Physiology · Endocrine physiology: growth hormone

Sample item

A man has coarse facial features and enlarged hands. In a healthy person an oral glucose load lowers serum growth hormone. In this patient, which result would support acromegaly?

AA rise in serum cortisol after the glucose loadBLow IGF-1 with a low fasting growth hormoneCGrowth hormone falls to undetectable levels after glucoseDFailure of growth hormone to suppress after oral glucose, with raised IGF-1

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

The answer and the reasoning

D. Failure of growth hormone to suppress after oral glucose, with raised IGF-1

Growth hormone is secreted in pulses and is suppressed by hyperglycaemia. In acromegaly the autonomous pituitary adenoma does not suppress, and serum IGF-1 (which reflects integrated growth hormone secretion) is raised. The oral glucose tolerance test with growth hormone measurement is the confirmatory test.

Option by option

A. A rise in serum cortisol after the glucose load
Cortisol is not the measured endpoint of this test.
B. Low IGF-1 with a low fasting growth hormone
Low IGF-1 suggests growth hormone deficiency, not excess.
C. Growth hormone falls to undetectable levels after glucose
Suppression to very low levels is the normal response and excludes acromegaly.
D. Failure of growth hormone to suppress after oral glucose, with raised IGF-1 (correct)
Correct. Non-suppression after glucose with raised IGF-1 confirms autonomous secretion.

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.

Questions about this Physiology question

What is the answer to this Physiology question?

The best answer is D, Failure of growth hormone to suppress after oral glucose, with raised IGF-1. Growth hormone is secreted in pulses and is suppressed by hyperglycaemia.

Why is "A rise in serum cortisol after the glucose load" not the answer?

Cortisol is not the measured endpoint of this test.

Why is "Low IGF-1 with a low fasting growth hormone" not the answer?

Low IGF-1 suggests growth hormone deficiency, not excess.

Why is "Growth hormone falls to undetectable levels after glucose" not the answer?

Suppression to very low levels is the normal response and excludes acromegaly.

What concept does this question test?

It tests Endocrine physiology: growth hormone in Physiology. In acromegaly the autonomous pituitary adenoma does not suppress, and serum IGF-1 (which reflects integrated growth hormone secretion) is raised. The oral glucose tolerance test with growth hormone measurement is the confirmatory test.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. 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 Endocrine physiology: growth hormone?

For each system, sketch the key graph (pressure–volume loop, oxygen dissociation curve, nephron handling) and explain it aloud. Then use the flashcards and the other Physiology 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.