If urine concentrates with administration of ADH analog, the kidneys are responsive and the problem is with ADH production in the hypothalamus or release in the post. pituitary.
These always tripped me up:
+ Polydipsia= responds to water deprivation, low serum Na
+ Central= responds to vasopressin, high serum Na
+Nephrogenic = responds to nothing, normal serum Na
lynnI think serum Na+ only depends on the patient's access to water. FA19 pg 344 says serum osm is high in both and doesn't mention Na specifically. Spent a while double checking for DI, but low serum Na for polydipsia is definitely correct. +1
drzedIn general, SIADH or polydipsia will cause HYPOnatremia, and DI (central or nephrogenic) will cause HYPERnatremia, but in the latter--as you stated--water access change the serum Na. +1
submitted by โhayayah(1212)
Pt has diabetes inspidus.
If urine concentrates with administration of ADH analog, the kidneys are responsive and the problem is with ADH production in the hypothalamus or release in the post. pituitary.