Endocrine Disorders - Pituitary Flashcards
Where does GnRH come from?
hypothalamus
–> Stimulates release of LH/FSH from pituitary
What distinguishes microadenomas from macroadenomas?
Micro: 1cm, headaches, visual disturbances, hormone deficits (GH, LH/FSH, TSH, ACTH), elevated prolactin (stalk compression), functional or non-functional
What is treatment of adrenal insufficiency?
Primary: gluco + mineralocorticoid
Secondary: glucocorticoid only
Stress dosing: dose doubled/tripled
What does LH do?
Promotes secretion of testosterone from Leydig cells
Side effects of testosterone
Progression of prostate cancer
Worsening of BPH
Polycythemia
Oily skin/acne
Most common cause of primary hypogonadism?
Klinefelter’s disease (long arms; anger; small, firm testicles)
Others: any injury to testicles
Signs and symptoms of GH excess (acromegaly)
Large hands and feet Enlarged nose, tongue, lips Protruding jaw, gaps between teeth Bony ridge above brows Thickening of skin, large pores Excessive sweating
HTN, edema, hyperglycemia, cardiomegaly, sleep apnea, arthritis
What does FSH do?
Stimulates spermatogenesis from Sertoli cells
If hypogonadism occurs before puberty…
Boy will have underdeveloped sex organs, lack of secondary characteristics, eunuchoid habitus
If hypogonadism occurs after puberty….
loss of libido, thinning of facial/body hair, gynecomastia, infertility, erectile problems, low BMD/fractures, hot flashes
What hormones are produced by the pituitary gland?
ACTH FSH GH LH TSH prolactin
How do you test for acromegaly?
Test for IGF-1 (insulin-like growth factor-1) –> mediator for GH
GH is pulsitile, not a reliable test
Secondary hypogonadism will be due to
Injury/dysfunction of pituitary
If low T in hypogonadism, then
measure FSH/LH
IF high –> primary
IF low –> secondary
1 v 2 difficult to distinguish clinically
How do you treat pituitary tumor?
Surgical removal +/- radiation
Hormone replacement
