Endocrine - Adrenal Disease Flashcards
what cells does a pheochromocytoma arise from?
chromaffin cells of the adrenal medulla
what do chromaffin cells produce?
catecholamines
what genetic conditions does pheochromocytoma have associations with?
MEN 2
NF1
Von Hippel Lindau Syndrome
features of a pheochromocytoma?
headaches palpitations anxiety pallor erratic BP sweating
Ix for pheochromocytoma?
24hr urinary collection for catecholamines
plasma catecholamines
genetic testing
Tx for pheochromocytoma?
alpha then beta block
e.g doxasozin then atenelol
CCBs
surgery
why is the Tx in the order that it is for pheochromocytoma?
if beta blocked first, adrenaline would bind to all the free alpha receptors
causing unopposed vasoconstriction
stroke and BP increase
what are the layers of the cortex of the adrenal gland? what do they produce?
glomerulosa = MCT fasciculata = cortisol reticularis = sex hormones
what is addison’s disease?
autoimmune destruction fo the cortex causing hypoadrenalism (low cortisol)
what occurs in primary addison’s disease?
destruction or dysfunction of the gland
what occurs in secondary addison’s disease?
inadequate ACTH from the pituitary, leading to decreased cortisol
what occurs in tertiary addison’s disease?
inadequate CRH from the hypothalamus
leading to inadequate ACTH production
features of addison’s disease?
fatigue low BP diarrhoea wt loss nausea salt craving poor wound healing hyperpigmentation
why does hyperpigmenttaion occur in addison’s disease?
high levels of ACTH bind to melanocytes receptors
Ix for addison’s disease?
U+Es (low Na, high K) Ca (high) FBC synacthen test CT
