I had a lecture on Nephrology today - at 9.30 am on a Sunday morning . The Doctor asked this -
How will you decide whether you patient is drinking excess water to combat excessive urine loss [ eg - in Diabetes insipidus ] , or losing excess urine due to excessive water intake [ eg - psychogenic polydypsia ] ?
Reminded me about that world famous PJ -
Did the chicken come first or the egg ?
[ We got the correct answer anyway ]