Symptoms
Acute vs. Chronic: Acute can be fatal. There are signs of acute that must not be ignored and include extreme lethargy that may seem like the cat is barely conscious, fever, breathing troubles, and sometimes inability to walk/move properly, and you could see something like a drunk cat or similar to hypoglycemia. The symptoms below are for chronic pancreatitis attacks.
1. Meatloaf posture/hiding - doubled over as cats do when in pain, and many will hide because in the wild, animals will hide so that others cannot see them in pain and attack them when vulnerable. Just trying to touch the midsection will result in growls, bites, and sometimes ripples on the abdomen from pain. The pain is present in all cats and must be addressed with a sharp type of pain med, with buprenorphine being the most common.
2. Nausea - all will be nauseous, and a few even vomit. There are a variety of meds that may help, but I believe that ondansetron seems to work very well as does injecting famotidine (i.e. Pepcid AC) and sometimes cerenia.
3. Appetite - non existent, and even the smell will cause cats to turn away, or even vomit. NOTE: an appetite stimulant will not fix this problem until the nausea is addressed and resolved (refer back to #2).
4. Blood glucose - goes up, and diabetics who are home tested will present higher BG and need higher doses in many cases. Very rare would it be to see a cat with low, normal BG and positive for pancreatitis.
5. Variety of other possible symptoms, but for the most part, they all stem from the above 4 points. Yes, the cat will lose weight and be dehydrated because the cat is not eating or drinking.
Testing
fPLI test
under 3.5 = negative
5.0 and over = positive
In between 3.5 and 5 is iffy but you should still treat as if it were pancreatitis. The vet may do a snap test, but it's not great because a positive does not tell you if the cat is at 3.6 or 36, and the difference is huge. You need the fPLI to know exactly what is your cat's condition.
Treatment
Treatment is short and sweet: 3 things are needed for at least 4-5 days for a chronic flare.
Long term treatment should include weekly B12 injections (cyanocobalamin) because one of the many benefits gained from B12 is treating inflammation. B12 can possibly eliminate, or at least greatly lessen, the inflammation which is attacking the cat's pancreas. Cats who have pancreatitis attacks are prone to have more, so you want to keep watch for the signs that YOUR cat has during a flare.
For more in-depth information, check out this Primer on Pancreatitis and the Pancreatitis Yahoo Group.
Thanks to Gayle for compiling the information for this helpful guide.