Undiagnosed illness

[kittyface]

Hello my 12 yo cat has lost half her weight vomiting with diarrhea containing partially formed stool. Her stomach makes a symphony of gurgling noises. Vet did blood tests and physical exam and everything was normal.  He couldn't get fecal sample treated her for worms with no improvement.  

She eats constantly, drinks a large amount of water but is losing weight and becoming weak.  We already spent $200 trying to diagnose her ailment and I'm at a loss as to solutions.  What do you recommend?  Thanks.

[Aleda M Cheng, D.V.M., C.V.A]

The most common causes of unexplained weight loss while still eating and drinking are the following: Diabetes, Hyperthyroid, gastrointestinal ( GI) cancer, and inflammatory bowel disease (IBD).

If she has already tested negative for diabetes and hyperthyroid, that leaves GI cancer and IBD.

IBD sometimes improves with the use of oral or injectable steroids, a novel protein hypoallergenic diet, symptomatic medication and herbal formulas.  GI cancers can be benign or malignant and ultrasound may help to diagnose a GI cancer or other abnormality.

[kittyface]

Thanks so much -- you gave more information than the vet!