Posterior pituitary Flashcards
AVP increases water reabsorption via
aquaporin 2
loop diuretics for SIADH
furosemide
Bumetanide
Psychogenic polydypsia vs DI
psychogenic will have lower serum sodium (over-drinking)
osmotic vs non-osmotic diuresis urine osmol
non-osmotic
osmotic >300
presentation DI
polyuria
serum sodium high-normal
causes central DI
autoimmue immune injury to hypothalamus / pituitary
head trauma / surgery
cerebral hypoperfusion
tumors (pituitary A, cranigiopahyrngioma, meningioma)
infiltratve disorders (sarcoidosis, histiocytosis
polyuria with osmotic diuresis ddx testing
osmolal gap >10maOsm/mg = exogenous solutes
gap
SIADH volume status
euvolemic (typically
vasopressin receptor antagonists for SIADH
conivaptan
talvaptin
neurogenic DI =
deficient production/release of AVP
DI Rx and treatment
desmopressin - synthetic ADH
NSAIDs - to inhibit renal plastaglandins to stop inference with AVP
Thiazide diuretic (enhanced with amiloride)
Low salt, low protein diet
polyuria with non-osmotic diuresis ddx testing
water restriction test
urine osmolaity 300 = DI
normal plasma osmal = psychogenic polydipsia
in H20 deprivation test, if serum osmol goes above normal and urine osmol doesn’t increase, indicates___-
diabetes insipidous
causes nerphrogenic DI
xlinked recessive disroders
hypokalemia
hypercalcemia
srenal disease
drugs
nephrogenic DI=
renal resistance to AVP
