Endo Path - Adrenal (FA) Flashcards
What is the dexamethasone test and implications of a positive result?
Administer high dose dex. If no decrease in serum ACTH, the source is ectopic. If decrease, Cushing disease confirmed
What is the most common cause of ACTH-independent Cushing syndrome?
Adrenal tumor
What are the labs that are indicative of primary hyperaldosteronism?
HTN, hypokalemia, metabolic alkalosis, LOW Renin
What is the pathophysiology of secondary hyperaldosteronism?
Low renal blood flow –> overactive RAAS (High Renin)
What is the pathophysiology of Addison Disease?
Chronic primary adrenal insufficiency due to atrophy or destruction (autoimmune, TB, mets). Def in aldosterone and cortisol –> hypotension, hyperkalemia, acidosis, hyperpigmentation.
What is the pathophysiology of hyper pigmentation in Addison?
incr. ACTH –> incr. MSH
What part of the adrenal is spared in Addison?
The medulla only
What is the pathophysiology of Waterhouse-Frederichsen syndrome?
ACUTE primary adrenal insufficiency from adrenal hem.
What are associated with Waterhouse-Frederichsen syndrome?
Neisseria meningitidis septicemia, DIC, and endotoxic shock
3 y.o. child with distended abdomen, homovanillic acid in urine, and histologic small, round, blue cells with rosettes? Name the oncogene.
Neuroblastoma. N-myc
What is the most common adrenal medulla tumor in adults? What is the cell responsible and the embryo origin of these cells?
Pheochromocytoma. Chromaffin - neural crest
25 y.o. with episodic HTN, headache, sweating, palpitations, and pallor with increased serum catecholamines and urinary VMA?
Pheo
What other diseases are associated with pheochromocytoma?
MEN2A/2B and VHL
What are the diseases of MEN2A?
Medullary thyroid cancer
Parathyroid adenoma
Pheo
What are the diseases of MEN2B?
Medullary thyroid cancer
Mucosal neuroma
Pheo