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Flashcards in Adrenal disorders Deck (28):

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
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


What is pheochromocytoma

Non-malignant lesion of adrenal medulla to overproduce catecholamines


What are the symptoms of pheochromocytoma

Episodic hypertension, headache, sweating, tremor, palpitations


What is the best diagnostic tests for pheochromocytoma

Best initial test: Plasma free metanephrines

Best cionfirmatory test: 24 hour urine collection for metanephrines

Next step: CT/MRI or adrenal glands or MIBG scanning (nuclear isotope scan telling location of pheochromocytoma if outside adrenal gland)


What is the treatment for pheochromocytoma

1.) Phenoxybenzamine - alpha blocker best initial therapy
2.) Beta blocker or calcium channel blocker - useful afterRemove surgically