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hey guys how do u differentiate betw psychogenic and DI....
please give me concept...how.

one thing what i have read is that for psychogenic polydipsia, there is an underlying psychological disorder..... am not sure

water restriction results in increased urine osmolarity in psychogenic polydipsia but not in DI

anyone have any better explanation...

in my question in uworld..the water osmolaritiy has gone up even in DI...so im kind of confused...

what was the Q? may be they had given ADH/ vasopressin.. and after that it rises in central DI..

yes they gave them adh..gimme ur email. i will email u the question.. i can put it on word....ill be wating for ur email

thats what i was saying.. if u give ADH in CDI, osm will go up bcoz the defect here is ADH def.. but in primary polydipsia, ADH levels and function is normal.. the only problem is excess of water intake.. so when u do water deprivation, osmolarity will improve (by the action of ADH hormone in the body).. in CDI, it will not improve with water deprivation..
i dont think u need to send me the Q for this.. :-)
or u still dint get it?

hey pankyash,
in primary polydipsia...when we give vasopressin why doesnt the osmolarity go up...isnt the function of adh to increase the osmolarity.....

see for the D/D of all these, the first test u do is water deprivation test.. to check if its just a polydipsia.. so if the patient does not respond to this, then u give ADH and see if osm goes up.if ya then its CDI.. and if still no response, its NDI..
no use giving ADH in polydip patient bcoz the main reason for polyuria in that is excess water intake.. he doesnt have any problem with his ADH.. its normal.. so no point giving ADH if u dont restrict water first..
hope i made it somewhat clearer..