Diabetes Insipidus Flashcards
condition that results from a deficiency of or insensitivity to ADH, resulting polyuria and inability to concentrate the urine?
Diabetes insipidous
What are the types of DI?
- central
- nephrogenic
- psychogenic
What is the cause of central DI?
- damage to the hypothalamus or pituitary gland causes decreased ADH production or release
- may be permanent or transient
What is the cause of nephrogenic DI?
- defect in the renal tubules that results in renal insensitivity to ADH
- unresponsive to vasopressin
What are the symptoms of DI?
- changes in LOC
- irritability
- hyperreflexia
- polydipsia
- hypotension
- tachycardia
- polyuria
- signs of dehydration
What labs findings are seen in the assessment of a DI pt?
- hypernatremia
- low urine specific gravity
- low urine osmolality
- hypokalemia
- hypercalcemia
- increased serum osmalilty
What diagnostic test is done to assess a pt with DI?
- CT/MRI of brain/hypothalamus/pituitary gland to r/o tumors/bleeding/swelling
- Vasopressin challenge test
A vasopressin challenge test should be order if which type of DI is suspected?
Central DI
What is considered a positive result for a vasopressin challenge test?
- reduce thirst and polyuria
- sodium level remains the same
A positive vasopressin challenge is indicative of which type of DI?
Central DI
What will the results of a vasopressin challenge be in a pt with nephrogenic DI?
- negative
- there will be no clinical improvement
Desmopressin should be used for which type of DI?
Central
Hydrochlorothiazide with potassium supplement is order for which type of DI?
Central and nephrogenic
What is the maximum dose of hydrochlorothiazide when used to treat central/nephrogenic DI?
50 mg qd
Drug managment for tx of nephrogenic DI?
- indomethacin-hydrochloride (25-50mg qd)
- indomethacin-desmopressin
- indomethacin-amiloride
