Adrenal Disease Flashcards
What hormones are produced by the adrenal cortex?
ZG: Mineralcorticoid, Aldosterone
ZF: Cortisol and Androgens
ZR: Under constant ACTH control “basal” secretion of cortisol (always some there just in case)
What is produced by the adrenal medulla?
Catecholamines: Epinephrine, Norepinephrine, Dopamine
These aren’t subject to hypothalamus action-required to act quickly
What do Mineralocorticoids stimulate?
Aldosterone stimulates sodium reabsorption = water retention and potassium excretion.
What are androgens excreted by the adrenal cortex precursors for?
testosterone and estrogen
What are adrenal medulla hormones responsible for?
catecholamines are responsible for fight or flight, sympathetic NS response. These are not under pituitary control, controlled by sympathetic NS via direct neural stim. Types:
- norepinephrine
- epinephrine
- dopamine
Where is cortisol produced and what is it’s function?
Adrenal cortex
functions as another stress hormone.
receptors (glucocorticoid) are found in virtually all tissue functions as:
Stress response
Glucose metabolism (increases gluconeogenesis)
Regulates metabolism of proteins and fats
calcium homeostasis
suppresses immune response
Maintains circadian rhythm
peripheral vasc. tone
increases cardiac output
Diurnal excretion of cortisol?
cortisol is at it’s highest at 6:00am (when melatonin is lowest)
Cortisol is at it’s lowest at 12:00am (when melatonin is at it’s highest)
When is cortisol secreted?
Exercise and stress-increases C.O
Vascular tone-Increases Periph. resistance
Acute Trauma-regulates inflammation
What can occur if cortisol is given in excess or used chronically?
HTN Peptic ulcer Decreased estrogen/testosterone increased appetite Decreased cognitive fxn. euphoria depression irritability Decreased immune response
Define Acute Adrenal insufficiency
Emergency caused by insufficient cortisol
Rapid tx is essential to save life (cardiac collapse)
What are the 2 types of adrenal insufficiency?
Primary (adrenal insufficiency)-adrenal failure to produce cortisol
Secondary (Pituitary insufficiency) -pituitary failure to produce sufficient ACTH
What is the MC cause of acute adrenal insufficiency?
Abrupt discontinuation of adrenocortical (prednisone)
What are possible triggers of latent adrenal insufficiency?
Stress Removal of hypercortisol secreting adrenal tumor w/suppression of other adrenal gland Pituitary necrosis Trauma Adrenal hemorrhage Anticoagulant (warfarin)
Clinical findings of Acute adrenal insufficiency
GI-abd pain/diarrhea, salt craving (mc in chronic)
Psych/neuro-HA, Confusion, coma/cerebral edema
Systemic-weakness, fever
CV-hypotension
Skin-hyperpig
Endocrine-Hypoglycemia
Lytes-hyponatremia, hyperkalemia,
Lab findings of Acute adrenal insufficiency
Low cortisol, and high ACTH, low aldosterone - dehydration and volume contraction
diagnostic tests for Acute adrenal insufficiency
-Co-synthropin ACTH stim test: After IM injection of co-synthropin, cortisol levels measured at 30 and 60,
Normal-~20mcg/dL
Abnormal (adrenal insuff)- < 20 mcg/dL because ACTH fails to tim adrenal glands.
-ACTH will also be very high because there is little or no negative feedback
ddx for acute adrenal insufficiency
Shock
Hyperkalemia
hyponatremia
tx for acute adrenal insufficiency
High index of suspicion-treat immediately!!!
Hydrocortisone (1st line)
Continuous IV saline 5% dextrose restore plasma volumen and hypoglycemia
tx infections empirically (don’t wait for cultures)
Rapid tx is essential and life saving!!!
What is the most common cause of chronic adrenal insufficiency in the US?
Addison’s disease
What are the causes of chronic adrenal insufficiency
Addison's dz: autoimmune (idiopathic) - distraction of adrenal cortex Infection-TB in developing nations Fungal Chronic use of steroids-blunting of ACTH/CRH response Metastatic ca. HIV Iatrogenic (ketoconazole, steroids) women>men 30-60yo
t/f Addisons disease is characterized by HIGH ACTH and LOW glucocorticoid (cortisol)
T!
signs and symptoms of chronic adrenocortical insufficiency
Intolerance to physical stress
constitutional sx-weakness, fatigue, low grade fever
skin-hyperpigmentation, creases
GI-anorexia, weight loss, abd. pain, Anorexia n/v, SALT craving, signs of dehydration
CV-Hypotension, orthostatic hypotension, shock, small heart
MSK-myalgias arthralgias
Neuro-delayed DTR’s, anxiety irritability
Psych-lethargy, confusion, psychosis
diagnostics for chronic adrenocortical insufficiency
hpoglycemia
plasma ACTH elevated
Low serum sodium
Elevated potassium
Low plasma cortisol @8am w/ elevated plasma ACTH
antibodies for autoimmune dz
Co-synthropin (ACTH) stim test-failed adrenal response
tx of chronic adrenocortical insufficiency
Replacement of glucocorticoids and mineralocorticoids
- hydrocortison/prednisone-lowest effective dose to avoid Cushingoid s.e., increase dose at times of illness
- Fludrocortison (aldosterone)-If there is hyponatremia, hypokalemia, dehydration, postural hypotension
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