qqq - 2confused2bdoctor

[ArchivalUser]

A 45 yr. old male complains of gradual weight gain over the past several years. His
fingers have enlarged so much that he can no longer wear his wedding ring. He sweats
more than usual, and in particular, his hands are constantly sweaty. He has also noticed a
gradual coarsening of his facial features. An MRI reveals the presence of a 1.5-cm tumor
in the anterior pituitary. Which of the following endocrine abnormalities is likely to be
present?
A Decreased plasma growth hormone concentration
B.Decreased plasma IGF-1 concentration
C. Decreased plasma insulin concentration
D. Impaired glucose tolerance
E. Increased suppression of growth hormone secretion with oral glucose

[ArchivalUser]

ddd

[ArchivalUser]

ddd

[ArchivalUser]

agree d

[ArchivalUser]

All correct..The correct answer is D. The patient probably has acromegaly due to a growth hormonesecreting adenoma in the anterior pituitary. Hypersecretion of growth hormone in an
adult will not cause an increase in stature, since the epiphyses of long bones have already
fused. However, overgrowth of bone in the face and skull produces the characteristic
protruding jaw and forehead observed in this disorder. Soft tissue proliferation leads to a
coarsening of facial features. The hands and feet are particularly affected, producing large
and thickened spade-like fingers and toes. Excessive growth hormone decreases the
sensitivity of peripheral tissues to insulin ("anti-insulin" effect). This tends to raise blood
glucose and produce a compensatory hyperinsulinemia (not decreased plasma insulin,
choice C) that functions to limit the hyperglycemia. Approximately 50% of patients with
acromegaly show impaired glucose tolerance.