Flashcards in anterior pituitary disorder-Table 1 Deck (33):
What are the hormones of the anterior pituitary?
FSH, LF, ACTH, TSH, Prolactin, GH FLAT P(I)G
What are the hormones of the posterior pituitary?
Oxytocin and ADH
Feminization or masculization, LHRH—>LH/FSH—> testosterone, estrogen, progesterone. Mediated by negative feedback loop
Hypothalamus pituitary thyroid axis?
TRH—>TSH—>T4—>T3 , negative feedback loop, Metabolic control and appetite control
Growth hormone axis?
GHRH—>GH—>(LIVER-IGF-1) AND TARGET ORGANS, HYPOGLYCEMIA WILL INCREASE GH, SOMATOSTATIN NEGATIVELY REGULATES AP
HYPOTHALAMUS-PITUITARY ADRENAL AXIS
(emotion can increase CRH) CRH—>ACTH—>(ADRENALS-CORTISOL—>DOWN REGULATE IMMUNE SYSTEM AND GLYCOGENOLYSIS), MSH, (HYPOGLYCEMIA POSITIVELY AFFECTS AP)
adrenals cannot release cortisol, low negative feedback on hypothalamus(high crh), high ACTH, high MSH(dark pigmentation)
dopamine inhibit ap to secrete prolactin, Prolactin releasing factor(TRH) stimulates ap to produce prolactin, dopamine can be inhibited by antipsychotics, PRF can be stimulated by serotonin(SSRI and TCAs), dopamine can be increased by DA agonists.
Hypothyroidisms affects on prolactin secretion
(high TSH/TRH), Low TH, low T3/T4, increased TRH to compensate will increase prolactin secretion …..
suckling, uterine distension—>oxytocin—>breast lactation, uterine/cervical contractions, psych effects(
baroreceptors(inc ANP-atria), osmoreceptors in hypothalamus(high tonicity)—>ADH—>vasculature(inc PVR), kidneys(inc aquaporins in collecting ducts)= increase bp
What are the most common mechanism for hyperpituitarism?
Adenoma(secretes prolactin), damage to pituitary stalk, drugs(SSRI, antipsychotics, alpha-methyldopa, cocaine), hypothyroidism(inc TSH)
What are the s/sx of prolactinomas?
females: amenorrhea and galactorrhea males: gynecomastia, decreased libido, ED and bitemopral hemianopsia(macroadenoma only=lateral visual field deficits)
How do you dx hyperprolactinoma?
Prolactin levels and TSH levels, then MRI(r/o adenoma)
What is the treatement for hyperprolctinoma?
Dopamine agonist(cabergoline and bromocriptine)
What is acromegaly caused by?
Macroadenoma secreting GH often
What are the clinical presentations of acromegaly?
onset 20-40s, gender equal, skeletal changes(first), corsening facial features, enlargement of hands/feet(ring doesn’t fit), deepening of voice, carpal tunnel syndrome, CHF(lastly)- ALWAYS IN Adult —can see bitemporal hemianopsia also
What is the differnece between acromegaly and gigantism?
Gigantism occurs in children, while acromegaly occurs in adults
How do you dx acromegaly?
IGF-1 level, can be done with direct GH level with 100g glucose(expect low growth hormone level- low glucose levels cause increased gh normally), MRI needed for diffinitive dx
What is tx for acromegaly?
Transphenoidal resection(resect adenoma) or octreotide (rx), can include dopamine agonist(cabergoline/bromocriptine)
PANHypopituitarism is caused by?
Pituitary apoplexy(hemorrhage) and sheehan’s syndrome(ischemia-postpartum), inflitrative disease(sarcoidosis, hemochromatosis, tb, syphilis), non-functioning adenoma, trauma, stroke, mass effect
What are the clinical presentaiton of pituitary apoplexy?
acute HA, nausea, vomiting, altered mental status, low bp, low blood sugar(low cortisol)
What are the clinical presentation sof sheehan’s syndorme?
Postpartum, extended amenorrhea(>3months), low bp during delivery, difficulty breastfeeding, hypotension(low cortisol), HELLP syndrome(high liver, low platelets)
how do you dx hypopituitarism?
LH/FSH(changes first)—>GH—>TSH—>ACTH, Measure levels of AP hormones- and MRI (r/o adenoma or r/in apoplexy)
How do you measure GH?
IGF-1 level or direct GH with insulin—> administer insulin=inducing hypoglycemia then see if GH increases. If GH is
How do you measure ACTH?
Indirectly via cortisol
How do you measure TSH?
directly via TSH, T3, T4
How do you treat pituitary apoplexy?
surgical decompression and hormone replacement
Empty sella syndrome clinical presents as?
often incidental, benign intracranial htn, HA and systemic hypertension in obese women
how do you treat empty sella syndrome?
You don’t need to treat
illuminates everywhere there is CSF