Always happy to try to help but this time I don't know if I can add anything! Your vet seems pretty thorough!
Well, the vomiting does not fit with diabetes insipidus, and neither is the sudden onset, but it could fit with a urinary tract infection, or early kidney disease. Your dog's body may be trying to dilute out a current infection by increasing thirst. The urinalysis may not show anything simply since any abnormality is too diluted out. This goes for blood, bacteria and other abnormalities. An eight hour water deprivation may not be long enough to change a urinary specific gravity.
If a bladder and abdominal X-Ray has not been performed than it should be. It is great that a urine culture and sensitivity is pending, and I would have the abdominal ultrasound performed. Even though a test for hyperadrenocorticism was performed a couple of years ago I think that it would be a good idea to repeat it since a lot can change in a couple of years for a dog with their accelerated life spans. It would not hurt to test for diabetes insipidus either. Diabetes Insipidus can occur with other diseases and is very controllable with Desmopressin Acetate. The cognitive disorder drug Anipryl can also be helpful for polyuria/polydipsia (excessive drinking and urination) as it's side-effect.
Another uncommon possibility is psychogenic polydipsia and just means that your dog may have a behavioral drinking problem.
This is a tough one and when all else fails in traditional veterinary medicine than maybe a consultation with a holistic vet may shed additional light on the problem. I would exhaust all the current traditional tests first though.
Please let us know the results of the tests!
did ur vet do a water deprivation test?or suspect diabetes insipidus?google this in canines and see if he fits the symptoms.My female greyhound was dx'd with this at age 9 and gone at age 11.Insatiable thirst for water....but minus the other symptoms ur describing.
I should add that he did this excessive drinking/urinating thing a couple of years ago, and Cushings was tested for and ruled out.
diabetes insipidus much different that the Cushings.Small gland in base of brain by pituitary starts 2 shrink causing the thirst.....if she's doing it again might need another current water deprivation test to rule this in/out.
He's still peeing tons of very dilute urine, but not particulary drinking excessively. I'm really confused about this.
He's had 2 days of Clavamox so far. I've been keeping him on Pepcid every 12 hours and he's only vomited once in the past 2 days.
A bladder/abdominal xray was performed a few months ago, the last time he had a UTI. Probably will do the ultrasound in a week or two.
It figures my dog might have a drinking problem, since his mommy likes to drink a bit.
Thank you, as always, for your input. I'll let you know if anything develops. We'll give it a bit more time.
The culture came back E. Coli this time. Last time it was Klebsiella.
He'll be on Clavamox for a couple months at $60/week. Yikes!
wow where did he get that?my greyhound was on Atopica for his intestinal lymphantegica that occurred after a rabies shot.15 tabs at $58....took 3 a day!over $400 a month for this alone not counting antibiotics for diarhhea...blood levels....CBC's.....i was fortunate i could do this for him or would have had to put him down.thank god its not diabetes insipidus..the most cost effective price i could find on these in 2001 was 100 pills at $282.....66 day supply and u don't want to buy from mexico or spain for u don't know if ur getting the real thing or bootleg!their needs medically are about the same as a humans!but then veterinary medicine is almost or just as difficult as med school and vets are not in biz to give their services away..their time xpertise and training is worth something..just like a doctor and they have overhead and staff to pay as well!