? Please Recommend What Pancreatitis Test to Get

I need help because I am so overwhelmed and the veterinarians around here are useless.

My cat Brownie is 14 and is now up to 1.50 units of Lantus, but I cannot keep her regulated. I have not seen numbers under 150 since June. She eats low carb wet food only. I feed her Sheba pate and Fancy Feast pate. I just eliminated Friskies pate from her diet thinking maybe she needs very low carbs. But now her glucose is back in the 250-350 range! It's possible she's gotten into the other cats' dry food without me knowing it, but she only would've eaten about 20 pieces (I only put small amounts on it).

I strongly suspect she has pancreatitis or EPI, but am confused as to the best method of diagnosis (and my vet is not helpful, nor is the specialist). An ultrasound was inconclusive, but evidence points to pancreatitis. What blood test do we need to get done? I've been reading about them, but the articles seem contradicting, leaving me very confused. Can I just get a spec fPL from the vet's office or do we need more thorough tests like the fTLI, fPLI, cobalamin and folate test? I'm going to take Brownie to the vet next week and insist on regular blood work and something to check for pancreatitis, but I need to know what test to get. We were going to do testing through TAMU back in June, but the vet didn't think it was necessary, so we didn't do it. I regret that now. Should've followed my gut feeling.

Also, I realize my spreadsheet is not up-to-date. I haven't had time to enter it. It's on paper though, I'm still keeping track.

 

This is probably why her BG is high.....we've seen cats that ate just a few pieces (like 3-5) that went up 200+ points.

The best diagnostic test for pancreatitis is the Spec fPL but pancreatitis is notoriously hard to diagnose/treat.

Have you read our "Primer on Pancreatitis"?

Unfortunately, without an updated spreadsheet, there's not much we can offer in the way of advice. I know it sometimes feels like a lot to do, but it really is important and there may very well be other clues to what's going on that an up to date spreadsheet will show

If you can at least go back for 2-3 weeks, that may help

 

The sped fPL (Idexx) and and fPLI (TAMU) are basically the same:
"The Spec fPL Test was developed from the fPLI test in partnership with Drs. Williams and Steiner at the Gastrointestinal Laboratory at Texas A&M University."
above from:
http://www.idexx.nl/smallanimal/reference-laboratories/testmenu/innovative-tests/spec-fpl.html

If concerned about another GI problem then other blood tests are required. Idexx does do:
GI Panel 2 (Folate/Cobalamin TLIwith Spec fPL® Test - Feline† (test number 2283)
https://www.idexx.com/en/veterinary/reference-laboratories/tests-and-services/