Adrenal Disorders

Question 1

adrenal medulla

Answer 1

• inner part of adrenal gland

- source of catecholamines (epinephrine and norepinephrine); richly innervated, extension of sympathetic nervous system

Question 2

adrenal cortex

Answer 2

-secretes steroid hormones

Question 3

5 groups of steroid hormones

Answer 3

• BASED ON RECEPTOR BINDING SITES
• mineralocorticoids: aldosterone
• glucocorticoids: cortisol
• androgens: testosterone, DHEA
• estrogens: estradiol, estrone
• Progestins: progesterone

Question 4

diseases of the adrenal cortex

Answer 4

• cort insuff: adrenal crisis, addison’s dz
• cort excess: cushing’s
• aldo excess: primary hyperaldosteronism

Question 5

diseases of adrenal medulla

Answer 5

-pheochromocytoma –> the only clinically important dz of the medulla

Question 6

adrenal insufficiency: primary vs. secondary

Answer 6

• low cort
• primary: low serum cort, high ACTH - adrenal gland is not responding to ACTH
• secondary: low serum cort, low ACTH - pituitary not responding to feedback

Question 7

acute adrenal insufficiency

Answer 7

• adrenal crisis
• emergency! cort insuff
• usually seen with withdrawal from exogenous steroids; post-operatively or with systemic use for chronic insufficiency
• weakness, abdominal pain, fever, confusion, n/v/d, low BP, dehydration, increased skin pigment

Question 8

chronic adrenal insufficiency

Answer 8

• Addison’s disease (uncommon)
• weakness, easy fatigability, anorexia, weight loss, low BP, small heart
• n/v/d, abdominal pain, muscle and joint pain, amenorrhea, sparse axillary hair, increased skin pigmentation (esp creases, pressure areas, nipples)

Question 9

stress dosing

Answer 9

-before surgery, you give steroids to balance them

Question 10

Primary adrenal insufficiency causes

Answer 10

• autoimmune dz (most common)
• adrenal infections and inflammation
• bilateral metastases
• after adrenalectomy
• adrenal hemorrhage or necrosis
• idiopathic
• drug-induced
• congenital disorders

Question 11

secondary adrenal insufficiency causes

Answer 11

• acute interruption of prolonged glucocorticoid therapy (most common)
• acute adrenal crisis - shock syndrome (most common)
• pituitary or hypothalamic tumor
• pituitary irradiation, surgery or brain trauma
• pituitary infections, inflammation, hemorrhage or necrosis

Question 12

lab findings for adrenal insufficiency

Answer 12

• CMP with high K, low Na, high Ca, high BUN
• CBC with mild anemia, neutropenia with lymphocytosis and eosinophilia (chronic)
• low plasma cort at 8am
• high ACTH in primary adrenal dz

Question 13

test needed for dx of adrenal insufficiency

Answer 13

• cosyntropin stimulation test
• synthetic ACTH (250mcg) given parenterally; draw blood 30-60 mins later; failure of serum cort to rise is diagnostic –> bolus of ACTH should drive cortisol production but if it doesn’t then its diagnostic
• low cort and low ACTH = secondary or tertiary adrenal insuff
• low cort and high ACTH = primary adrenal insuff

Question 14

tx of adrenal insufficiency

Answer 14

• replace cort with hydrocortisone (or other form)
• tx infections aggressively; stress dosing appropriate –> if they have an infection, you need to increase cort level so their body can fight it off

Question 15

cushing’s syndrome

Answer 15

• clinical manifestations caused by excessive corticosteroids
• facial plethora, proximal myopathy, striae, easy bruising
• central obesity, muscle wasting, thin skin, hirsutism, purple striae, osteoporosis, HTN, poor wound healing, psych changes, HA, polyuria, polydipsia, acne, nephrolithiasis
• “moon face,” “buffalo hump,” supraclavicular fat pads, protuberant abdomen, thin extremities
• oligo/amenorrhea, impotence

Question 16

cushing’s dz vs syndrome

Answer 16

• dz = hypercort due to ACTH hypersecretion from pituitary (most common)
• syndrome = hypercort due to any cause

Question 17

lab findings for cushings syndrome

Answer 17

• impaired glucose tolerance and insulin resistance, hyperglycemia, hypokalemia, normal Na on CMP
• leukocytosis, lymphocytopenia on CBC

Question 18

cushing’s syndrome first line tests for diagnosis

Answer 18

• late evening salivary cortisol level
• 24 hr urine for free cort
• low-dose dexamethasone suppression test
• AT LEAST TWO OF THESE SHOULD BE ABNORMAL TO DIAGNOSE CUSHINGS SYNDROME
• once hypercortisolism is confirmed, plasma ACTH is ordered to find cause

Question 19

low-dose dexamethasone suppression test

Answer 19

• standard screening tests to distinguish patients with Cushing’s disease (Cushing’s syndrome caused by pituitary hypersecretion of ACTH) from most patients with the ectopic ACTH syndrome (Cushing’s syndrome caused by nonpituitary ACTH-secreting tumors).
• overnight 1mg test: administer dex at 11pm to 12am, measure serum cortisol @ 8am –> most normal people have serum cort @ 8am of less than 2mcg/dl (55nmol/L)

Question 20

who do you test for hypercortisolism

Answer 20

• pts with high likelihood of dz
• osteoporosis or HTN in young pts
• multiple progressive sxs of cushings
• unexplained severe fractures
• adrenal incidentalomas
• low index of suspicion: 1 test
• high index of suspicion: 2 tests
• exclude exogenous glucocorticoid use

Question 21

testing ACTH to determine cause of Cushings syndrome

Answer 21

• suppressed ACTH (<5pg/mL) = ACTH independent Cushing’s syndrome –> adrenal CT/MRI
• intermediate ACTH (5-20pg/mL) –> CRH test –> no ACTH response = ACTH independent cushings. +ACTH response = ACTH dependednt cushings syndrome –> CRH stimulation and dex suppression tests, OR pituitary MRI
• normal to high ACTH >20pg/mL = ACTH dependent cushing’s syndrome –> CRH stimulation and dex suppression rests, OR pituitary MRI

Question 22

MCC of cushings syndrome

Answer 22

cushings dz!!!

• originates from pituitary –> high serum cort, high ACTH
• 2nd MC = ectopic ACTH syndrome –> MOST COMMONLY FROM LUNG CANCER!!
• 3rd = Adrenal adenoma

Question 23

primary hyperaldosteronism

Answer 23

• HTN and hypokalemia are classic presentation
• resistant HTN primary reason to consider this dx
• polyuria, polydipsia, muscular weakness
• elevated plasma and urine aldo levels, low plasma renin
• most common subtypes = aldo-producing adenoma and bilateral idiopathic hyperaldosteronism
• Tx: adrenalectomy, aldosterone antagonists (spironolactone or epelerenon = 1st line for meds), then potassium sparing diuretic (amiloride)

Question 24

pheocromocytoma

Answer 24

• tumor in adrenal medulla - rare cause of HTN
• attacks of HA, perspiration, palpitations, tachycardia, anxiety
• HTN may be sustained, resistant to therapy or paroxysmal, esp in relation to stress

Question 25

lab findings and tx: pheochromocytoma

Answer 25

- elevated urinary catecholamines or metanephrines; plasma fractionated free metanephrines most sensitive but many false positives - follow progression using CT or MRI if positive - tx is surgical resection of tumor

Question 26

adrenal fatigue

Answer 26

- group of related s/sxs that results when adrenal glands fn below necessary level - associated with intense stress and often follows chronic infections like bronchitis, flu, or PNA - theres no science to back it up!! - the symptoms are vague and can be attributed to many other dzs - symptoms: weight gain, irritability, overly emotional, frequently sick