End 5 - Other Adrenal Pathology Flashcards
What does Aldosterone do?
The main mineralocorticoid of the body, regulates Na+, K+, and indirectly water levels: increases Na+ resorption in kidneys (and water follows). Regulates salt and water balance (sweat glands and GI tract). Increases K+ excretion in kidneys.
What 3 things will increase aldosterone secretion?
Increase in K+. Decrease in Na+ and H2O. Angiotensin II.
What things will decrease Aldosterone secretion?
Increase in Na+.
What mineralocorticoid do we use for a dangerous aldosterone deficiency?
Fludrocortisone.
What is Primary hyperaldosteronism?
Caused by aldosterone-secreting adrenal tumor (Conn syndrome): this causes HTN, Hypokalemia and Metabolic alkalosis (from the increased dumping of K+ which causes increased urinary H+ loss and the hypokalemia detected in blood is trying to be countered by cells pumping K+ into the blood, which must exchange for H+ going into the cell). Also causes low plasma renin due to (-) feedback.
What is secondary hyperaldosteronism?
Kidneys perceive low intravascular volume (i.e.: renal artery stenosis) causing an aggressive activation of RAAS. This causes High plasma renin, which leads to high aldosteronism.
What conditions can lead to kidneys perceiving low intravascular volume?
Renal artery stenosis. Congestive heart failure. Low protein states: cirrhosis, nephrotic syndrome.
What two meds can we use to treat hyperaldosteronism?
Spironolactone and Eplerinone.
What is Primary adrenal insufficiency? What are the causes?
Failure at the adrenal glands. AKA Addison’s disease. Causes hypotension, hyponatremia, hyperkalemia, generalized fatigue, anorexia, weight loss, and skin hyperpigmentation. 90% of causes are caused by auto antibodies that destroy the adrenal glands; the rest can be by metastatic cancer or TB or Waterhouse-Friderichsen syndrome.
What is Waterhouse-Friderichsen syndrome?
Acute primary adrenal insufficiency due to adrenal hemorrhage caused by severe meningococcal (Neiserria) sepsis or DIC.
What is the difference b/w primary and secondary adrenal insufficiency?
Primary is adrenal glands being affected. Secondary is at the level of the pituitary; since only ACTH is low, it will NOT cause hyperkalemia, hypotension, or Hyperpigmentation, in contrast to primary adrenal insufficiency. However we do see weakness, malaise and weight loss on both.
What is Tertiary adrenal insufficiency? What would be the cause?
When the hypothalamus is not secreting CRH (Corticotropin releasing hormone), therefore no ACTH to Cortisol. But there is sufficient aldosterone therefore no hypokalemia nor hypotension. Most commonly caused by abrupt withdrawal of long term corticosteroids.
What is the most common tumor of adrenal medulla in adults?
Pheochromocytoma.
What is Pheochromocytoma?
Most common tumor of adrenal medulla in adults. Associated w/ MEN 2A and 2B and Neurofibromatosis I. It is derived from chromaffin cells (neural crest origin). It produces catecholamines which lead to episodes of HTN, headaches, palpitations, tachycardia, and diaphoresis. [Rule of 10s] 10% are malignant, 10% bilateral, 10% extra-adrenal, 10% calcify and 10% are in children. It is one of 4 tumors that can secrete erythropoietin.
How do we diagnose Pheochromocytoma?
Look in the urine or serum for its breakdown products:Metanephrine, Normetanephrine, Vanillylmandelic acid (VMA, which is only in urine). Or check catecholamine levels itself.
