Adrenal disorders Flashcards
(28 cards)
What is Cushing’s syndrome and Cushing’s disease
Cushing’s syndrome: Increased cortisol
Cushing’s disease: Increased cortisol from the result of overproduction of pituitary ACTH
What is the percentage of the different causes of increased cortisol
Pituitary ACTH (cushing’s disease): 70%
Adrenals: 15%
Unknown source: 5%
Ectopic ACTH: 10%
What are the symptoms seen in someone with cushing’s disease
Fat redistribution - moon face, truncal obesity, buffalo hump, thin extremities
Skin - striae, easy bruising, thinning of skin
Osteoporosis
Hypertension - increased sodium reabsorption
Sexual: Menstrual disorders in women, erectile dysfunction in men
Polyuria from hyperglycemia
What diagnostic tests should be performed to establish presence of hypercortisolism
Best initial test: Both 24 hour urine cortisol
and 1mg overnight dexamethasone - if morning cortisol suppressed then no hypercortisolism
What are other exceptions to cortisol being risen
Depression, alcoholism, and obesity
After confirming that there is hypercortisolism through the 24 hour urine test, what is the best way to find the cause/location of hypercortisolism
ACTH levels - if elevated, then pituitary or ectopic source such as lung cancer or carcinoid
What is the next step after ACTH levels are found to be elevated
Brain MRI to see if pituitary is cause
If no mass seen in pituitary but high dose dexamethasone test was able to suppress it, it probably is in the pituitary and the next step is to then sample inferior petrosal sinus (venous drainage of pituitary) for ACTH after CRH injection, and if seen positive then it means pituitary is source (too small for MRI)
If still no ACTH, then scan chest to see if ectopic source
What is the problem with scanning first as opposed as biochemical testing
You may find abnormal pituitary but this is abnormal in 10% of people and is benign anyways
What effects on lab values does hypercortisolism have and wy
Affects distal kidney potassium and hydrogen secretion, resulting in hypokalemia and metabolic alkalosis. Also get hyperglycemia and hyperlipidemia
Leukocytosis occurs from demargination of white blood cells
What is the treatment for hypercortisolism
Surgically remove pituitary via transphenoidal surgery
Laparosocopic removal for adrenal sources
What should you do for the evaluation of an adrenal incidentaloma
4% of people will have this, just do metanephrines of blood/urine to exclude pheochromocytoma, renin/aldosterone to exclude hyperaldosteronism, and 1mg overnight dexamethasone suppression test
What is the result of high dose dexamethasone suppression if hte source of the hypercortisolism is adrenal, pituitary, or ectopic
Ectopic - no suppression
Pituitary - high suppression
What is hypoadrenalism
Also known as addison’s disease, it is an autoimmune destruction 80% of cases, other causes include TB infection, metastasis
What is adrenal crisis
Severe form of adrenal insufficiency caused by hemorrhage, surgery, hypotension that rapidly destroys gland, can also be caused by quickly removing prednisone
Presentation is hypotension, fever, confusion, and coma
What is the presentation of someone with addison’s disease
Weakness, fatigue, altered mental status, NV, anorexia, hyponatremia, and hyperkalemia
Hyperpigmentation from very high ACTH-MSH but usually needs to be chronic
Women will lose axillary and pubic hair because androgens produced by adrenals, while men maintain them because they are produced by the testes
What is the best test to see if someone has hypoadrenalism
Cosynthropin stimulation test - synthetic ACTH, measure cortisol before and after, if it does not rise then this confirms that it is addisons and that hte source is adrenals
Will also see eosinophilia
What would you expect for lab values of someone with hypoadrenalism
Opposite of cushings - hypoglycemia, hyperkalemia, metabolic acidosis, hyponatremia
What is the treatment of addison’s disease
This time want to use something that has both mineral and cortisol effects - hydrocortisone
Second line - fludrocortisone, if hydrocortisone doesn’t work
If someone has adrenal crisis, do not diagnose. Just treat, what should you give them
Hydrocortisone - patient will present after some trauma and have high eosinophil count, hyperkalemia, hyponatremia, and hypoglycemia
What is primary hyperaldosteronism and what are the causes
Autonomous overproduction of aldosterone with low renin activity, almost always benign
Solitary adenoma - 80%
Bilateral hyperplasia - 20%
What are hints to suggest that patient has hyperaldosteronism
High blood pressure and hypokalemia (in form of muscle weakness or diabetes insipidus)
What is the order of diagnostic tests in hyperaldosteronism
Best initial test: Measure ratio of aldosterone to plasma renin (if renin elevated, then no primary hyperaldosteronism)
Most accurate test: Sample of venous blood draining adrenals measuring aldosterone
Final step: CT scan
What is the treatment for hyperaldosteronism depending on the cause
Adrenal adenoma - laparoscopic removal
Bilateral hyperplasia - eplerenone or spironolactone
What are the side effects of spironolactone
Antiandrogenic - decreased libido, gynecomastia
