[Gusgus mommy]

My yorkie is an 8 year old male. He was previously about 5lbs but in the last couple of months has gone down to about 4lbs. In the last 3 weeks we have been to the vet about 8 times, 2 overnight stays and 1 late night urgent care visit. His symptoms started with
-loss of appetite. This has since come back however he is very finicky on what he will eat.
-Dehydration which he is drinking water regularly now and we give subcutaneous fluids periodically at vets suggestion
-extremely loud gurgling noises from stomach
-stomach pains and shaking during digestion
- lethargy, this comes and goes
- nausea (excessive licking of lips)
- hunched back
- horrendous breath, toxic smelling
- not fully digesting food ( this was found during endoscopy when there was still food found in stomach after 14 hours.
The vet has determined an extremely high BUN (at one point 184) but is being controlled with fluids. (Creatine is normal)
He has blood in his stool
He does not have diarrhea
Occasional vomiting, once in the last couple of weeks ( which has been the norm since he was a puppy. ( came to me with hypoglycemia and sensitive stomach as a puppy)
He had biopsy of his intestines taken yesterday which we are awaiting the results. The endoscopy showed inflamed intestines and also ulcers on his gums.
He is currently taking 3 medications, 1for nausea, 1 antacid and another for ulcers.
I have nothing conclusive and have so far spent $4000 in the last 3 weeks. If the biopsy comes back inconclusive I'm at a loss.
Gus is currently eating whatever I can get him to eat, although he is hungry he is just picky. Currently he is eating very lean ground turkey and a little cottage cheese. Pancreatitis has been ruled out but ibd and kidney disease have not yet been ruled out. Gus is my world and it is so terrible and terrifying to see him so ill for such a prolonged period of time.

Any thoughts or suggestions would be very helpful.