Pituitary Pathophysiology (5/15) Flashcards
What can cause pituitary hypersecretion of a hormone?
Only pituitary adenomas
What can cause pituitary hyposecretion of a hormone?
- Any dis of pit or hypothalamus can cause deficiency of any hormone made by the ant pit
- Only a dis or hypothal or infundibulum can cause a def of vasopressin and thereby cause diabetes insipidus
What happens when you have a deficiency in GH?
- Short if prior to epiphyseal closure
- Dec muscle mass and inc fat
- Dec bone mineral density
What happens when you have a deficiency in prolactin?
Dec lactation
What happens when you have a deficiency in ACTH?
Hypocortisolism
What happens when you have a deficiency in TSH?
Hypothyroidism
What happens when you have a deficiency in LH/FSH?
Hypogonadism
How do we treat GH def?
Somatotropin (synthetic GH) which promotes bone growth in children and improves BMD in adults
What are the cells in the pit that produce peptide hormones? Whats special about them?
Somatroph, lactotroph and corticotroph
-Adenomas in these cells tend to produce physiologic effects
What are the cells in the pit that produce glycoprotein hormones? Whats special about them?
Gonadotroph, thyrotroph
-Do not cause physiologic effects so they are harder to recognize
What are the clinical syndromes associated with somatotroph adenomas?
- Gigantism (before epiphys closed)
- Acromegaly (after plate closure)
What are the features of acromegaly?
Facial: large nose, ears, lips with prominent jaw.
Hands: large with large fingers
What are the consequences of acromegaly?
- Osteoarthritis
- Colon cancer
- CVD
- Diabetes
- Neuropathy
- Sleep apnea
- Inc mortality
How do we diagnose acromegaly?
Chemical:
- Lack of suppression of GH to an oral glucose load
- Elevated serum IGF-1
Pathologic:
- Histologic appearance of pit adenoma
- Immunospecific staining for GH
How do we treat acromegaly?
- Surgically
- Pharma
- Radiation