Endocrinology Flashcards
Women with hyperglycemia identified during the first trimester are classified as having type 2 diabetes instead of gestational diabetes.
You can use metformin as long as GFR>____
45
Empty Sella Syndrome
1)Primary: Intracranial HTN
2)Secondary: to infarction of a pituitary tumor or other causes including infection, autoimmune disease, trauma, or radiotherapy
Empty sella hints at some kind of pitutiary dysfunction
1) Such as Prolactinoma
it is recommended that asymptomatic patients with empty sella have repeat endocrine, radiologic, and ophthalmologic evaluation in 24 to 36 months.
____ is a drug associated with hypogonadism
Chronic Opiates
____ is an emerging oncological cause of panhypopit
Immune checkpoint inhibitor
Markers to assess for pitutiary hypersecretion when a pitutiary mass is found _____ and _____
IGF-1, Prolactin
Markers to assess for pitutiary hyposecretion_____
AM Cortisol, FSH, LH, TSH
Urine osmolality >750-800 mOsm/kg H2O is a normal response to water deprivation, indicating ADH production and peripheral effect are intact.
If dilute urine, it means no ADH to retain water
Desmopressin challenge is used to diagnose_______
Central DI
Test for GH excess___________
Glucose tolerance test
Women with a macroadenoma close to the optic chiasm who are planning pregnancy may benefit from surgical decompression of the pituitary tumor due to the risk of enlargement during pregnancy. Macroadenoma defined >1cm
Somatotrophs and gonadotrophs appear to be the most sensitive to injury, so GH as well as LH and FSH are the most common pituitary deficiencies.
Morning cortisol levels less than 3 µg/dL (82.8 nmol/L) are diagnostic of cortisol deficiency; however, a morning cortisol level greater than 15 µg/dL (414 nmol/L) likely rules it out. Patients with cortisol levels between 3 and 15 µg/dL (82.8-414 nmol/L) should undergo an ACTH stimulation test
Cushing disease is the result of excess____
ACTH
Once diagnosis of ACTH-dependent Cushing syndrome is established, a pituitary MRI should be performed for confirmation. If no pituitary tumor is seen or if the tumor is less than 6 mm, a high-dose 8-mg dexamethasone suppression test (DST) is done to evaluate for the presence of an ectopic ACTH-producing tumor (lung, pancreas, thymus carcinoma most commonly), which is highly resistant to dexamethasone suppression
When is petrosal vein sampling indicated: ______
1) MRI negative or lesion <6mm
2) S/p surgery and continued ACTH hypercortisolism
If medical management is needed for cushings due to non-candidacy for radiation or surgery____
Pasieriotide, cabergoline, ketoconazole
Hard to test for cushings when someone is on hormone therapy,
Initial Cushing test
1) Urine 24hr
2) 1mg DST (low dose)
3) late night salivary cortisol
*Repeat testing is recommended for confirmation
Primary aldosteronism is caused by hyperplasia of both adrenal glands (idiopathic hyperaldosteronism) in two-thirds of cases,
The most reliable case-detection test is calculation of an plasma aldosterone-plasma renin ratio (ARR) by measuring plasma aldosterone concentration and plasma renin activity (or direct renin concentration)
In patients taking an ACE inhibitor or an angiotensin receptor blocker, renin should be elevated, so in these patients, a simple initial test is plasma renin activity measurement. If the plasma renin activity is suppressed, the likelihood of primary aldosteronism is high and an ARR
situation where renin activity is more useful
Treatment of Conns syndrome
Medical therapy with an aldosterone receptor antagonist (spironolactone or eplerenone) is the treatment of choice for primary aldosteronism due to idiopathic hyperaldosteronism
Conditions associated with pheochromocytoma_____________________
MEN2, VHL, NF1
The classic triad of palpitations, headache, and diaphoresis is seen in fewer than 50% of patients with pheochromocytoma
Initial tests for pheochromocytoma include measurement of plasma-free metanephrine collected in a supine position or 24-hour urine fractionated metanephrine and catecholamine levels
Medications effecting test: SSRI/SNRI, Levodopa, methyphenidate,
They are typically larger on imaging>4cm, compared to Conns syndrome, catecholamine-secreting tumor is high, the next step is iodine 123 (123I)-metaiodobenzylguanidine scanning
Pre-surgery: Phenoxybenzamin, Selective α-1 receptor blockers such as doxazosin can be used as an alternative to phenoxybenzamine if availability or lack of insurance coverage of the latter is a problem.
MEN1 associated with ___________________
Gastrinoma, insulinoma, pituitary adenoma
The most common cause of primary adrenal insufficiency in the United States is autoimmune adrenalitis, and positive 21-hydroxylase antibodies are found in approximately 90% of those cases
Evaluating adrenal insufficiency____________
1) AM cortisol –> ACTH , <3 with high ACTH is already diagnostic of primary adrenal insufficiency
2) If AM cortisol 3 - 15 (indeterminate), ACTH stim test , low cortisol means adrenal insufficiency because gland did not respond
Low cortisol low ACTH = secondary adrenal insufficiency from pituitary malfunction
For minor physiologic stress states such as respiratory infection, fever, or minor surgery under local anesthesia, patients should double or triple their baseline glucocorticoid dose for 2 to 3 days. H
Patients who present with adrenal crisis should receive fluid resuscitation and an initial immediate dose of intravenous hydrocortisone (100 mg), followed by intravenous hydrocortisone (100 mg) every 8 hours for the next 24 hours, with subsequent dosing governed by clinical status
Patients with concomitant untreated adrenal insufficiency and hypothyroidism should always receive glucocorticoid replacement therapy first to prevent precipitation of adrenal crisis by thyroid hormone replacement