Adrenal Flashcards
(34 cards)
What 3 things are secreted form the Adrenal Cortex? Where are they located and what regulates them?
Aldosterone – the outer layer, regulated by Renin-Aldosterone Angiotensin System
Cortisol (major glucocorticoid) – middle & inner layer, regulated by ACTH from pituitary
Androgens (testosterone, androstenedione, DHEA, and estradiol) – the inner adrenal cortex, regulated by ACTH
What is the function of cortisol?
- Inhibits insulin secretion, increase hepatic gluconeogenesis, decreases protein stores
- Dampens defense mechanisms
- Inhibits production or action of inflammatory mediators
* Required for production of angiotensin II (without it leads to hypotension & death) - Lowers serum Calcium
* Necessary for normal bodily function
When is cortisol secreted?
response to stress, trauma, infection, and major surgery
What happens if there are excessive amounts of corticosteroids?
Cushing Syndrome
What are the 2 sources for Cushings syndrome?
Endogenous – tumors secreting cortisol or ACTH
Exogenous – glucocorticoid administration (drugs) *Most common
What types of endogenous tumors are there?
Adrenal tumors – secreting excess cortisol (ACTH suppressed)
Or Non-pituitary (lung CA)
What is the most common disorder of endogenous glucocorticoids in excess?
Pituitary adenoma secreting excess ACTH = Cushings DISEASE
When you hear “moon face” or “buffalo hump” what diagnosis do you think of?
Cushings Syndrome
What other signs & symptoms may a person with cushings syndrome present with?
Abdominal protuberance, striae, thin extremities, muscle wasting, acne, hirsutism, glucose intolerance, hypertension, osteopenia or osteoporosis, and increased thirst
What lab findings would you see with cushings syndrome?
hyperglycemia, elevated cortisol
If you see the elevated cortisol levels, what diagnostic test would you order?
Dexamethasone suppression test = 1mg give at 11PM, AM cortisol should be
What can happen if Cushing syndrome is left untreated?
Significant morbidity from diabetes, hypertension, susceptible to infections, and fractures.
How do you treat Cushings syndrome?
Transphenoidal resection of pituitary adenoma or laparoscopic resection of adrenal tumors
What medications can be used for metastatic adrenal CA?
Ketoconazole & metyrapone
Again, what is the most common cause of exogenous glucocorticoid excess?
Prolonged administration of synthetic glucocorticoids (steroids - prednisone)
Leading to chronic suppression of ACTH & the adrenals
What must we always remember about taking patients off of steroids?
MUST TAPER
What differential diagnosis must you always think of in a patient with fatigue, weakness, and hypotension?
adrenal insufficiency
What patients are at risk for adrenal insufficiency?
Those taking exogenous corticosteroids with suppression of hypothalamic pituitary axis
Steroids tapered too rapidly & requirement for cortisol increases
What type of diagnostic testing can you do for adrenal insufficiency?
Cosyntropin (synthetic ACTH) test – cosyntropin 250ug given IV, test serum cortisol 30-60minutes later, a NORMAL response would be a rise in serum cortisol to at least 20
Gives us an understanding of adrenal reserves
*If a patient is on oral steroids, they must hold for 8 hours
What disease is known as chronic adrenal insufficiency, and is also autoimmune?
Addison’s disease
What is occurring in Addison’s disease?
Autoimmune destruction of the adrenal cortex that can develop over time, resulting in chronic deficiency of cortisol, aldosterone, and adrenal androgens
What are the signs & symptoms of chronic adrenal insufficiency?
*Low BP, orthostasis, and hyperpigmentation of skin = must have a suspicion since sxs are non-specific
What does the lab work up look like for chronic adrenal insufficiency?
Neutropenia, lymphocytosis, eosinophilia;
LOW AM CORTISOL (
What diagnostics would you order is you see low AM cortisol levels?
Abdominal CT – showing small non-calcified adrenals
