In psychogenic polydipsia, serum sodium is low, and after water deprivation test, urine osmolality is increased.
Urine osmolality does not increase with vasopressin injection
In nephrogenic diabetes insipidus, serum sodium is high and there is no change/mild increase in urine osmolality after water deprivation
yotsubatoThis patient does not undergo a water deprivation test +72019-06-10T11:08:20Z
niboonshCompulsive water drinking or psychogenic polydipsia is now increasingly seen in psychiatric populations. Effects of increased water intake can lead to hyponatremia causing symptoms of nausea, vomiting, seizures, delirium and can even be life threatening if not recognized and managed early.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579464/+52019-06-16T15:51:03Z
missi19998Just wondering why it in not resistance to ADH action of vasopressin+2019-06-23T19:42:28Z
amarousisbecause he would be hypernatremic with no ADH. can't resorb any water+12019-06-30T22:10:04Z
Yeah, so, turns out this is not Nephrogenic DI due to lithium use, you don't give lithium to treat schizophrenia.
mbourneIf it was Nephrogenic DI, you would have essentially have the effects of too LITTLE ADH. This patient shows severe hyponatremia, essentially the effects of too much water in the serum. This could be from SIADH or polydipsia, and the question stem and answer choices leave us with Psychogenic Polydipsia as the correct response.+2020-01-11T04:10:01Z
to snoo-finity ... and beyond!
submitted by masonkingcobra(104), 2019-05-23T22:44:19Z
In psychogenic polydipsia, serum sodium is low, and after water deprivation test, urine osmolality is increased. Urine osmolality does not increase with vasopressin injection
In nephrogenic diabetes insipidus, serum sodium is high and there is no change/mild increase in urine osmolality after water deprivation