I got this letter from a client today...any ideas??

"Over the last week she's been drinking excessive amounts of water (2 gallons in a 24 hour period when we didn't limit her). Knowing that excessive water consumption can be a symptom of some larger health problems we brought her to the vet for some tests. They tested her urine and there was no UTI and she didn't have diabetes. They ran a full blood test and it came back clean, nothing out of the ordinary. We also had an ultrasound done to check for blockages in the way of tumors or eating something she wasn't supposed to. It came back clean, as well as kidney function seems normal. She's been on antibiotics for about a week and is still drinking lots of water. We had an endocrine test done yesterday for Cushings Disease and will find the results out for that on Thursday (11/19).

The question I wanted to ask you, is if you have any insight or larger picture view, of anything you may have come across or been informed of that we may not have tested for, or that might be common in the breed.

Any information that you can provide would be helpful as we want to tackle anything early that our furry family member may have."

thanks for any help you all could give...

Why is she on an antibiotic? Prophylaxis for the excessive water drinking I assume?

Endocrine disorders would be high on my list, including not only Cushing's but also Addison's. But what kidney function tests were run? Creatinine or just BUN?

Diabetes insipidus is another metabolic decease that causes extreme urination and thirst with no other symptoms (note this is another decease different and not related from the regular diabetes).
A water deprivation test or an ADH trial with desmopressin is the test you need to have done in your dog.
It can be treated with desmopressin acetate (DDAVP).
It can be originated in the brain or the kidney.

Was thyroid checked - full panel? (T4 on regular bloodwork is not enough)

Liver is also considered with excessive drinking but would imagine that was included in bloodwork.

I would think a full panel was done (or hope so) including BUN, creatinine, phosphorous........ (since they say kidney function is normal)

Check this link for other causes of excessive water intake.

http://74.125.93.132/search?q=cache:WfT1spla-4UJ:www.vetinfo.com/ddrinkandurin.html+reasons+for+excessive+drinking+in+dogs&cd=4&hl=en&ct=clnk&gl=us

Also wondering why the dog was put on antibiotic?

Prayers it is nothing serious

ETA: Just a thought (if all tests are negative): have they switched food recently that may have an ingredient, or added something to the diet, causing the dog's thirst to increase?

Hyperestrinism mimics Cushings. There is a great endocrine tests at the Univ of TN Vet School - Dr. Oliver. He is very communicative. I recently went through this, and having a Cushings dog once, that was my first thought.

It could also just be psychogenic polyuria polydipsia.

As Breeder 24 said I would think of Diabetes Insipidus. However a water deprivation test can be dangerous. When my boy had the same symptoms my vet did a lot of research on this AND consulted with a top specialist who advised against the water deprivation test. I can not stress this enough!

Have they done a serum osmolality test? How bout testing the the urine specific gravity?

If you'd like more info feel free to email me privately.

Good luck in getting a prompt diagnosis and hope it's nothing too serious.

How old is this dog?

Might want to check for leptospirosis - early signs can include excessive water consumption.

What do you feed?

I notice my dogs drink a lot more now that they are on a higher quality high protein food.