Hello, and welcome to FDMB!
You've had some great advice from BJ and Wendy: Treating the UTI will help your kitty feel a lot better and should bring down the blood glucose level. And transitioning your kitty to wet low carb food will lower the blood glucose level even further. Your kitty may even be one of the lucky ones that doesn't need insulin.
Don't lose heart!
Would you like to tell us your kitty's name? And your name?
Eliz