Chapter 114 Adrenal Gland Disorders Flashcards
What are the zones of the adrenal cortex and what does each produce/secrete?
Glomerulosa - mineralcorticoids
Fasciculata - glucocorticoids
Reticularis - sex hormones
What system controls the mineralcorticoid layer (z. glomerulosa)?
RAAS
Renin-angiotensin-aldosterone system
What system controls the glucocortoid layer (z. fasciculata)?
Pituitary gland
What does the medulla of the adrenals secrete and what system controls that?
Catecholamines
Autonomic nervous system
What is a para-ganglioma tumor?
A neuroendocrine tumor that secretes catecholamines outside of the adrenal gland (extra-adrenal pheochromocytoma)
What is a Budd-chiari like syndrome sometimes seen with adrenal tumors?
When thrombi occur in the hepatic vessels, causing portal hypertension, resulting in ascites
What are major contraindications seen with aspirating adrenal masses?
Massive catecholamine release and hemorrhage
What medication is recommended to give prior to adrenalectomy when pheochromocytoma is suspected?
What is this class of medication?
Phenoxybenzamine
Alpha-adrenergic antagonist
What stimulates aldosterone secretion?
Angiotensin II release following activation of the RAAS.
What two mechanisms can activate the RAAS?
Decreased renal arterial perfusion
Hyperkalemia
What are the causes of primary hyperaldosteronism? (most common form)
Adrenocortical adenomas, carcinomas, bilateral adrenocortical hyperplasia
What are clinical and diagnostics findings with primary hyperaldosteronism?
Muscle weakness, hypokalemia, hypertension
How do you diagnose hyperaldosteronism?
Document elevated plasma aldosterone conentration or aldosterone:renin ration; one can also use the lack of suppression of aldosterone in a fludrocortisons suppression test
What are treatments for hyperaldosteronism?
Surgery, anti-hypertensive agenets, potassium supplementation, mineralcorticoid antagonists
What is the optimal screening test for Cushing’s disease in dogs?
LDDST (Controversial, ACTH is the best according to Behrend)
