CMDT DSA--GH, acromegaly, hypopituitarism

Question 1

hypopituitarism w/o mass lesions- congenital

Answer 1

• congenital hypopituitarism
• congenital isolated hypogonadotropic hypogonadism (affects GnRH, LH, or FSH)
• Prader-Willi syndrome
• Kallmann syndrome (impair GnRH)
• congenital GH def

Question 2

Laron syndrome

Answer 2

• AR
• mutations in the GH R- results in GH-resistance
• def in IGF-1- dwarfism
• prominent forehead, depressed nasal bridge, small mandible, central obesity

Question 3

gonadotrophic def (hypogonadotropic hypogonadism)- causes what?

Answer 3

-hypogonadism, infertility

Question 4

gonadotrophic def- causes

Answer 4

• congenital- lack of pubertal development
• isolated hypogonadotropic hypogonadism
• Prader-Willi syndrome
• acquired- gradual loss of facial, axilliary, pubic hair

Question 5

Prader-Willi syndrome

Answer 5

-cryptorchidism, mental retardation, short stature, hyperflexibility, autonomic dysregulation, cognitive impairment, hyperphagia with obesity, hypogonadotropic hypogonadism

Question 6

dx of ACTH def

Answer 6

• fxnal atrophy of adrenal cortex
• cosyntropic test- blood drawn for serum cortisol, ACTH, and DHEA- then synthetic ACTH is administered- cortisol < 20 indicates adrenal insufficiency

Question 7

GH stimulation test

Answer 7

only 66% sensitive- can do a therapeutic trial of GH tx

Question 8

imaging- indicated when?

Answer 8

-when a mass lesion is suspected

Question 9

tx for hypopituitarism

Answer 9

-H replacement!

Question 10

central diabetes insipidus- essentials of dx

Answer 10

• ADH def with polyuria (2-20L/day) and polydipsia

- hypernatremia occurs if fluid intake inadequate

Question 11

familial diabetes insipidus

Answer 11

• dominant- sx’s at 2 yo

- Wolfram syndrome- AR- DIDMOAD (diabetes insipidus, type 1 DM, optic atrophy, deafness)

Question 12

vasopressin challenege test

Answer 12

-desmopressin acetate intranasally- measure urine volume for 12 hrs b/f and after

Question 13

central diabetes insipidus- tx

Answer 13

-desmopressin acetate- intranasally every 12-24 hrs as needed for thirst and polyuria

Question 14

Acromegaly and gigantism- essentials of dx

Answer 14

• pit tumor
• gigantism b/f closure of epiphyses, excessive growth of hands, feet, jaw, internal organs
• amenorrhea, HAs, visual field loss, weakness
• soft, doughy, sweaty handshake
• elevated serum IGF-1
• serum GH not suppressed following oral glucose

Question 15

acromegaly and gigantism- lab

Answer 15

-serum IGF-1, PRL, glucose, liver enzymes and serum creatinine or BUN (liver failure or kidney dz can elevate GH), T4 and TSH

Question 16

acromegaly and gigantism- tx

Answer 16

• pituitary microsurgery- remove the adenoma
• cabergoline (dopamine agonist of choice- oral)
• octreotide and lanreotide (SST analogs)
• tamoxifen (selective estrogen R modulator)
• pegvisomant (GH R antagonist)
• stereotactic radiosurgery- in pts who dont achieve complete remission with surgery or medical therapy

Question 17

hyperprolactinemia- essentials of dx

Answer 17

• women- oligomenorrhea, amenorrhea, galactorrhea, infertility
• men- hypogonadism, dec libido and ED, infertility
• elevated serum PRL (PRL is normally elevated during pregnancy)
• CT scan or MRI- pit adenoma

Question 18

hyperprolactinemia- tx

Answer 18

• pregnant women w/ macroadenomas- continue tx with dopamine agonists to prevent tumor growth
• dopamine agonists
• surgical tx- for apoplexy or those that compromise visual fields