Steno:

I'm a little concerned that your vet may actually have really misdiagnosed Misty unintentionally!

Excessive water consumption, rapid weight loss, and enlarged kidneys with tenderness when picking her up could all be signs of renal failure (kidney disease).

We just lost our kitty Junior almost 2 weeks ago to feline CRF (chronic renal failure) and as his disease progressed he had the same symptoms...smelled peculiar, lost weight, excessive water consumption, lost appetite, and near the end he was tender and unhappy about being picked up. We were fortunate enough to catch the CRF early and managed his illness for about 1.5 years before he finally got visibly sick and succumbed.

Don't want to alarm you, but a blood screen would allow your vet to look at Misty's creatnine and BUN levels in her blood--two major signs of CRF. I pray for you & Misty that she turns out okay, but waiting 2 more weeks to find out could be serious for Misty.

Know that my sincerest thoughts and prayers are with you & Misty!