Siamese kitten vomiting and not eating

Question
My 8 month old Siamese kitten vomited and had diarrhea and would not eat or make a bowel movement for a few days (he continued to urinate).  He spent two days at the vet without eating or having a bm but his blood test came back fine, an x-ray showed up clear and an in-house fecal test was fine.  He began to eat a tiny bit so I took him home.  He ate and made a bowel movement last night night.  This morning, he had diarrhea, vomited a tiny bit three times and now he won't eat and is curled up on my bed.  I tried to get him to play and he looked excited, but didn't want to get up.  He also refused treats.  We are waiting for the external lab's fecal test to return, but I just don't know what it could be.

Answer
Hm, sounds like the vets are stumped, and I don't have any better idea than they would.  Have they treated him for his symptoms, just to make him feel better?  Sometimes getting the nausea under control with something like metoclopramide or calming belly upset with tagamet will help a great deal.  There is a medication called cyproheptadine that can act as an appetite stimulant, too.

One other thing I can think of that can be missed on regular blood tests is pancreatitis.  Blood tests do check for pancreatic function, but these levels aren't always off, even when pancreatitis is present.  The only very reliable blood test for pancreatitis is called a PLI, and there are only a few specialized labs that perform the test.  Blood would have to be overnighted to one of these labs for a PLI test.  Pancreatitis is a serious disease with no specific treatment.  Small meals must be force fed, in general, once vomiting is under control.  Some vets prescribe antibiotics, but this is controversial.  And the kitty must be kept hydrated with fluids under the skin, if necessary.  One of my kitties had pancreatitis that wasn't diagnosed on regular blood tests.  The vets figured he just had a virus that would pass.  We finally  brought him to a specialist who performed a PLI that confirmed pancreatitis, but by this time, it was too late to save him.  Pancreatitis is less common than other ailments that cause belly upset, but it may be something to think about testing for if the problem persists and nothing else is revealed.

Siamese are a little quick to give up when it comes to illness, I find, especially when it comes to eating.  They get anorexic quickly.  I always pick up a chicken breast and boil it when I have a sick Siamese.  This seems to be most tempting to them, and it's gentler on their stomach than most commercial cat foods.  Chicken breast can be fed in place of cat food for a couple of days without causing any nutritional deficiency, so if this will get him to eat, then by all means, feed it to him.  Sometimes if you mix in a little white rice that has been boiled until it's mushy, this will help satisfy him (although my cats generally won't touch the rice).  Once his belly is used to having food in it again, he should be more willing to get back onto his normal cat food.