Tests For Diabetes Insipidus And Cushings

[krissn333]

Those of you who have dealt with DI or Cushing's, can you tell me what tests you had done in order to get a diagnosis?

 

I've done some surfing on the subjects, but I really haven't had time to read very closely and I need information quickly. I have a feeling that my little Skimmie is having some issues that may be one of these things, and I am trying to get him in to be seen. I'd like to be armed with information once we're able to get an appointment.

 

He is drinking excessively and urinating excessively. At times it's like he can't even control the urination. Last night he was sleeping on my lap and he peed all over me while I was sitting in the recliner. His pee is so dilute it looks like water.

 

Over and over we've been to the vet for similar issues-excessive drinking and urination. Every time, the labs suggest MILD (as in, can barely diagnose it) UTI. We've done course after course of Clavamox, and we've done other antibiotics too, I just can't remember off the top of my head which ones. Every time, he seems to improve while on the antibiotics, but then the symptoms return as soon as he's off of them.

 

The vet we're currently seeing thinks it's just psychological and I really don't think that it is. However, due to a referral agreement between this vet and the practice I'd like to transfer to (see my thread called Vet's Offices for the story on that), I have to keep going to this vet until something else can be arranged. I of course can't get an appointment for him to be seen at the current vet (again, see Vet's Offices thread), but I can take a urine sample in tomorrow. So, for the time being I'll do that, but, once I can get him in at the new place, I'll want to be running other tests.

 

If you don't mind sharing how you reached a diagnosis of DI or Cushing's, please do. Sorry this is so long, but I'm just going crazy with this.

[Batmom]

If the labs suggest mild UTI, has a culture been done?

[Brooker914]

Definitely needs to be cultured if it hasn't already. Have X-rays or an ultrasound been done to rule out stones? Has any bloodwork been done to rule out liver or kidney disease, and diabetes? If not, that would be the first step before looking into Cushings disease or DI. Do you know what the urine specific gravity has been?

[TheFullHouse]

Kristin, when Emmy was diagnosed for Cushings her primary symptoms were anorexia, excessive water intake, excessive urination and she had the typical pot bellied look that dogs get who typically are diagnosed with Cushings. I've forgotten a lot of what was done so I looked up the two tests that Emmy had. I've copied and pasted the information so you will get a good idea of what tests are normally done.

 

"Urine Cortisol/Creatinine Ratio Test: Considered a screening test, this cannot diagnose Cushing's, but it can rule it out. A urine sample is examined for the relative amounts of cortisol versus a normally excreted protein metabolite, creatinine (the latter is used to control for the degree of dilution of the urine). The greater the ratio, the higher the cortisol level. High cortisol in urine is suggestive of high cortisol in the bloodstream. Many conditions other than Cushing's disease can cause false positives, so this test is not considered diagnostic. Nonetheless, if the cortisol/creatinine ratio is okay, the dog is not likely to be Cushingoid, so this is a good screening test.

 

ACTH Stimulation Test: A blood sample is taken as a baseline. Then, a dog is given an injection of ACTH, the hormone which stimulates the adrenals to release cortisol. One to two hours later, blood cortisol levels are measured. Given that a dog with Cushing's has a constantly overworked, overproducing set of adrenals, the cortisol reserves are much greater, and the Cushingoid dog will be able to respond to the ACTH with greatly elevated cortisol output. This test doesn't differentiate between forms of Cushing's (adrenal vs. pituitary). It is considered diagnostic 80-95% of the time. Half of adrenal tumors will not respond on this test, and 15% of dogs with pituitary tumors will not respond. Nonetheless, it is an easy test and is often used along with a low dose dexamethasone suppression test to diagnose the presence of Cushing's disease. It is also used as a monitoring test for dogs who are being treated for Cushing's disease with Lysodren.

 

Low Dose Dexamethasone Suppression Test: This is considered the best test with an estimated 90-95% ability to diagnose Cushing's disease. A fasted dog has a blood sample taken as a baseline in the morning. A small amount of dexamethasone, a synthetic glucocorticoid, is injected, and follow-up blood samples are taken 4 hours and 8 hours later. A normal dog's body will perceive the presence of dexamethasone and suppress cortisol output throughout the test. Cushingoid dogs will not suppress blood cortisol in response to the dexamethasone injection, because their feedback mechanisms are not working properly as explained above. This test does not differentiate between forms of Cushing's disease (adrenal vs. pituitary), although it may be suggestive. Dogs who suppress at 4 hours and rebound at 8 hours usually have pituitary tumors."

 

Emmy had the urine test and the ACTH test.

[krissn333]

Doesn't a culture have to be done using a morning catch? If yes, that would explain why we haven't done it. I can never do morning appointments (either I have to work or they don't have any available). Such will be the case this time too-I'll have to leave work, drive home, collect the pee, and drive it 30-40 minutes (probably more since it'll be rush hour) and hope to get it there by 5.

[Brooker914]

No the urine culture must be sterile, so a free catch sample won't work-a needle is inserted directly into the bladder.

[krissn333]

Brooker, specific gravity has always shown the urine to be a tad too dilute. He always explains it away though due to the fact that he tanks on water all the time.

 

Bloodwork has always been done and liver and kidney values are always fine, glucose is always fine.

 

Did a full thyroid panel once upon a time because he lost weight quickly and lost a bunch of hair-came back normal.

 

Oh, thanks for reminding me it has to be done via cystocentesis (sp?)...I knew that-duh!

 

Well we won't be able to do that this time because we can't get an appointment unless we wait about a week out. If the new vet comes through soon, we'll do the cysto right away.

[krissn333]

Judy, Skimmie has everything you mentioned except for the potbellied look. He is super skinny and I can't get weight on him, no matter what I feed him. He was chunky about a year and a half ago and then this cycle of the suspected UTI began and he dropped weight. Initially I was worried about diabetes mellitus, but his glucose has been fine.

 

How on earth do they figure out if the Cushing's is pituitary or adrenal? Ultrasound?

[Brooker914]

If the culture comes back negative, then your next step will likely be testing for Cushings with one or more of the tests that Jillysfullhouse listed. Diabetes insipid us can be hard, sometimes it's diagnosed by response to treatment, and that's usually why other diseases are tested for an ruled out first. Good luck with everything, let us know what the results are.

[msjpk]

I'm sorry, I can't get passed the sentence: "the vet thinks it is psychological" ** is he

talking about?? With that being said I would run not walk with the results to another Vet and try to get in touch with Dr. Couto. Good luck and keep us posted.

My collie had Cushings and the description is what is was. However, she did develop seizures.

[TheFullHouse]

Judy, Skimmie has everything you mentioned except for the potbellied look. He is super skinny and I can't get weight on him, no matter what I feed him. He was chunky about a year and a half ago and then this cycle of the suspected UTI began and he dropped weight. Initially I was worried about diabetes mellitus, but his glucose has been fine.

 

How on earth do they figure out if the Cushing's is pituitary or adrenal? Ultrasound?

 

Yep, ultrasound will tell you if it's adrenal, it would take a CT scan to be able to see the pituitary glad to diagnose pituitary cushings. Most vets will do the ultrasound first.

[Guest Geostar]

Have you had any blood work done on him? That will give you some idea.. .Best wishes as I KNOW how you feel. Our Maria is doing better with the Doxyclyine for tick borne disease, but, I know the vet will want to recheck her blood file, too. I'm there for you and your sweet boy.. Try not to let your anxiety show too much, as he'll pick up on and become more stressed.. God bless..

 

=star

 

Opps..missed the blood work. There is a tick borne disease in which the grey drinks a lot of water. Maybe, a round of Doxy wouldn't hurt?

Just a thought..nothing more..'cause I don't know what else.. But, I'm there for you!

 

PSS One other thing: Many diseases "mimic" each other! Don't jump to any conclusions! Get another oppinion..

[Guest KennelMom]

With Stella, we did an ACTH stim test and ultrasound to look at her adrenals. She drank a lot, peed a LOT, inappetance, her coat looked like crap - dried out and dull. If you search H&M for Stella or Cushings, you should find the thread where I detailed it all...I usually post all updates in the first post so it's easier to read the history....good luck I hope you find an easy/fixable solution

[greyhead]

It doesn't really *have* to be a cysto. People don't give their urine samples that way!

 

We went through something similar with Shane. Very long story. Short version: he did develop E. coli. Vet had always considered it mere incontinence. Nonetheless, after months of antibiotics, he still leaks. The only way he doesn't leak more substantially is by eating a medium-protein kidney food (by Royal Canin). His kidneys seem to be slightly impaired, but nobody can really get a handle on it, even by ultrasound. Recently he tested positive for Lyme, which can have this effect on kidneys and incontinent leaking, as can other TBD's, I believe. So that's another angle to at least consider, as Geostar suggested.

Edited January 11, 2012 by greyhead

[krissn333]

One of the antibiotics he's been on multiple times is Doxycycline, I do remember that. That's what we used the last time - he was on it for 4 weeks, symptoms improved, but, never got totally better.

[Batmom]

It doesn't really *have* to be a cysto. People don't give their urine samples that way!

 

Mary is right about that, on both counts.

 

The vet labs *want* a cysto sample and may get irritated if you don't send them a cysto sample, but then there was the time I sent them a midstream free catch from one of my dogs and it grew ... nothing ...... Now that was a truly clean catch .

 

It is better if you can do cysto but there are times when that is not possible. You do have to tell the lab -- don't lie about it -- because they have to interpret what grows on the plate. And of course use a clean container, clean the dog's genital area first, make sure you're getting midstream, not catching everything from the very start of the flow ..... Those things will help ensure a usable culture.

 

If his symptoms improve when he is on antibiotics, the culture & sensitivity would be the first thing I'd do. Gidget had a hard-to-cure UTI. Her infection came back as sensitive to both Clavamox and Zeniquin in the petri dish. In the dog, symptoms improved on Clavamox, but that drug was unable to totally clear her infection. We had to use several weeks of Zeniquin to knock it out.

[greyhead]

Morning, first pee, is best for the catch because that's when you're most likely to get the germs to show up.

 

You shouldn't need an appointment. You should just be able, by prior arrangement, to hand the container to the front-desk person (on your way to work?) and leave. You also need to think about how long the sample will be sitting around or refrigerated before the lab comes to pick it up, so 5:00 might not be ideal. Just depends on how things are set up at that practice. My vet was happy to let me know what time the lab pick-up would be for all tests we've done, and we were able to plan accordingly.

 

Good luck! Really hope this gets sorted soon for you and your pup!

Edited January 11, 2012 by greyhead

[krissn333]

Unfortunately I can't take a sample out there in the morning. I have to be in the office at 7:30am and their office doesn't even open until 8am and it's 30 minutes away. It won't go to the lab for normal UA - they do those in house, but yes, the culture would have to go out - but we'll have to get that through cysto most likely.

[Batmom]

It might be worthwhile to get a first-of-the-morning sample, pop it in your refrigerator, and take that to the vet for another in-house analysis before you do the cysto/culture. Might confirm an infection, which would be useful to know.

[krissn333]

Will it still be ok to use at 5pm if it was collected at 6:30am? Seems like they've told me before that it can't be more than 30/45 minutes old.

[Batmom]

It's OK to use if it's been kept in the fridge.

[krissn333]

10-4. I'll see if I can get a first of the morning sample then. Should be interesting with the snow they're predicting for tonight.

[Guest summernights]

Gem's main symptoms of Cushing's were non-stop drinking, peeing and UTIs. Vet did the urine test detailed above, and then did the all-day dexamethasone suppression test, which resulted in her diagnosis of pituitary-based Cushing's. Her case is a bit atypical as she didn't have the anorexia or pot-bellied appearance.

[krissn333]

I'm not sure I'm going to be able to get urine samples out to the vet today - it took me almost an hour to get here this morning due to the snow that we're having here. It's going to be even worse to get home, and then I'd have to make a drive that normally takes 30-40 minutes in good conditions. It's just not safe.

[cleptogrey]

checking to see what's up w/ the testing and results since i have been dealing w/ a similar problem.i've read and contributed to your other earlier posts as to excessive urination.

 

just brought my waterholic,felix, in AGAIN.....urine looked normal(same as the other 2 tests)his coat is EXCELLENT(so he is not thinking thyroid),weight is good, he looks like the picture of good health, lymph nodes are fine, heart- strong and steady. blood work should be back tomorrow. i am monorting his water intake for the next 24hrs. according to his weight is should be around 3 quarts, i believe he is most likely consuming 6-8quarts a day.i did mention water diabetes, my vet's reply was that it usually hits older dogs(felix is 5). we shall see and then i wonder if i will have to monitor his output as well. one step at a time. if the labs picked up today i should have a clearer picture by tomorrow afternoon and we will see how his kidneys are doing.

Edited January 17, 2012 by cleptogrey