The clinical presentation is consistent with acromegaly, which results from excess growth hormone (GH) production in the anterior pituitary gland. Excessive GH production leads to increased release of insulin-like growth factor 1 (IGF-1), the first-line screening test for acromegaly, from the liver.
Acromegaly most commonly results from a benign pituitary adenoma that autonomously releases excessive GH, in turn spurring the liver to produce excessive levels of IGF-1. Symptoms develop gradually over time and include generalized enlargement of bone and soft tissue (in particular, enlargement of hands and feet requiring resizing of shoes and rings), macroglossia, macrognathia, and development of symptoms of carpal tunnel syndrome. Comparing the patient's current appearance to old photographs can be helpful in accentuating the changes due to acromegaly. The first-line screening test for acromegaly is IGF-1; this is a more sensitive test than GH given that its levels are more constant than the pulsatile production of GH.
Maugans et al. provide an overview of the diagnosis and treatment of acromegaly. Diagnosis of acromegaly can be challenging, given the insidious progression of signs and symptoms. It is also associated with important systemic manifestations including hypertension, diabetes, hyperlipidemia, cardiomyopathy (cardiomegaly progressing to congestive heart failure is the primary cause of mortality), and obstructive sleep apnea. The primary approach to treatment is via trans-sphenoidal surgery to remove the source of adenomatous hyperplasia in the anterior pituitary gland.
Chanson reviews the pharmacologic approaches for the treatment of acromegaly. When surgery fails to correct the problem, medical treatment includes dopamine agonists (particularly cabergoline) or somatostatin analogs such as octreotide. A newer treatment option is pegvisomant, which blocks the action of growth hormone at the growth hormone receptor to reduce the production of IGF-1 in the liver. Optimal management with surgical and medical therapies can help guarantee a normal life expectancy for most patients with acromegaly.
Figure A depicts the classical facial features of acromegaly: a prominent jaw line (macrognathia) as well as frontal bossing (prominent, protruding forehead). These should be compared to an old ID photo to ensure that they represent a change in appearance over time. Figure B depicts macroglossia, a contributing factor to obstructive sleep apnea in acromegaly. Illustration A shows a sagittal MRI with a microadenoma in the sella turcica (in red on the right), as well as the optic chiasm, which can be disrupted by some pituitary adenomas. Illustration B shows the pertinent feedback loop relating GH and IGF-1, as well as the pharmacologic targets in this process.
Answer 1: The anterior pituitary gland produces growth hormone, which is central to the pathologic process in acromegaly. However, given the pulsatile production of GH throughout the day, the first-line screening test for acromegaly is IGF-1, which is produced in the liver.
Answers 3-5: These glands and organs are not directly involved in the pathologic process underlying acromegaly.
Maugans TA, Coates ML. Diagnosis and treatment of acromegaly. Am Fam Physician. 1995 Jul;52(1):207-13.
PMID:7604764 (Link to Abstract)
Chanson P. Medical Treatment With Dopamine Agonists or Somatostatin Analogs in Acromegaly. Neuroendocrinology. 2015 Feb 12.
PMID:25677539 (Link to Abstract)