I just read this thread now. From me and my Ralphie to you and your Ralphie, we are praying for good results and a quick recovery.
I too am now using Hills Prescription U/D after using such great stuff for the past 5 years. However, Wysong made him very sick, sicker than any other food he ever used. I know it's supposed to be excellent but not in our case.
Hills PD has been fine so far. I know how you feel.
Again, our T&Ps are with you!