Panda diagnosed Sept 2014 (6 y/o Swedish Vallhund)

[Panda's mom]

I'm new to this forum, referred by our veterinarian. Panda is a 6-year-old Swedish Vallhund who just started having problems with PD/PU in early September 2014. I brought her in for testing and she was found to have normal liver, kidney, and urine tests with no signs of diabetes. An ACTH stimulation showed a pre-stim baseline of 9.8 and a post-stim of 28.9. Ultrasound showed a normal left adrenal and a "mildly enlarged right adrenal, .65 -.75 cm." Her presumptive diagnosis is pituitary dependent hyperadrenocorticism and she's now had 6 days of trilostane 10mg twice daily (she weighs 25 lb). She goes back for another ACTH in two days.

Panda has no other signs of Cushings, but is still drinking a lot and urinating frequently. I guess my main concern is whether I've been too quick to start treatment -- are there any additional diagnostic tests we should do to confirm the diagnosis? We're leaving for a 3-week vacation in mid-October and I'd rather not have our dogsitter have to deal with the polyuria if we can get it under control before we go. We'll adjust her dosage of trilostane when we get the ACTH this week and repeat it again in 3-4 weeks. I'm comfortable with the dogsitter's ability to judge any changes in her health and get her in to our vet while we're gone (he's an in-house sitter).

I'd appreciate any suggestions from the experienced members of this forum.

Marilynne in Atlanta

[Silliam]

Welcome it is nice to meet you even tho I am not a veteran member here are my tips....
It could be that your dog is just not showing many symptoms. I know I took my dog too the vet years ago and they said only mild indications for cushings then a few years later I got a strong diagnosis. While I try not to think of the 'what if's' in life I do wonder what starting treatment early could have done. So either way go with your gut and remember only hind sight is 20/20. Luckily some of the meds today block cortisol instead of killing off adrenal glands which means by stopping them you can reverse their effects.
As for the sitter I am a big believer in flow charts so as soon as your pup shows signs they know what to do. And example would be, if one night the appetite is low have an action they take for that even if it is just re offer the food in 20mins
What is your main concern about having the dog sitter dealing with the pu/pd?

[labblab]

Hello and welcome! I am so pleased that your vet referred you to our forum :), but I do have some additional questions about Panda's diagnosis. :o

Aside from the elevated ACTH, were there no abnormalities at all noted in any of Panda's lab tests? This would be very unusual for a Cushpup since there is a fairly consistent profile of out-of-range values that typically accompany Cushing's (elevated liver enzymes, elevated cholesterol, some white blood cell abnormalities, dilute urine with low specific gravity, etc.). In fact, sometimes these lab abnormalities are noted in advance of developing strong overt symptoms.

A sudden onset of excessive thirst/urination in the absence of any other Cushing's abnormalities (behavioral or laboratory) does leave me scratching my head a bit. Nonadrenal issues can register a "false positive" on the ACTH as well as causing adrenal enlargement. It sounds as though your vet has ruled out other obvious causes for Panda's PU/PD, but I'm not sure I'm yet convinced that it's Cushing's, either. Is your vet certain that a hard-to-detect urinary tract infection is not at play? Are there any other aspects of Panda's health history or appearance/behavior that can lend any clues?

Marianne

[Panda's mom]

Thanks for your replies.

Labblab, I was wrong about normal urine tests: Panda's urine specific gravity was indeed low and we ruled out a urinary tract infection. She puts out a morning-sized volume of clear urine every 2-3 hours (although I think this might have decreased a little this week on the trilostane). Her only abnormal lab was an elevation in monocytes on the CBC -- her liver enzymes and cholesterol are normal.
I know she doesn't have a lot of abnormalities, but we think we've diagnosed her early. (My late old Vallgirl developed incontinence at age 12 that responded well to Proin, so I'm sensitive to urine loss as a symptom.) Panda has always had a voracious appetite, so I can't say that increased -- she's very healthy otherwise and has good energy and coat, etc. She lost urine on the couch one day and wet my bed the next two nights, and that's when I realized how much water she was drinking (we have another dog who also drinks a lot, so we replenish water often anyway). I suspected diabetes, the vet thought perhaps a UTI, but when tests ruled those out, she wanted to look for Cushings and did the blood tests and ACTH, then the ultrasound.

Silliam, thanks for the suggestion about the flow chart. That's a very good idea. I think just stopping the trilostane would be the best advice to give the dogsitter, but we're close to the vet and I'll let them know that he might bring Panda in if there are questions. He's very reliable and has had health problems himself, so I think he'll be able to handle things.

Marilynne in Atlanta

[molly muffin]

Hello and welcome to the forum.

What is your dogs weight and what dose of trilostane are you currently giving? The current recommendation for starting dose is 1mg/1lb. Trilostane can continue to lower cortisol on the same dose for 30 days or more.

Sharlene and molly muffin

[Panda's mom]

Hi Sharlene:

As I said in my first post, last week Panda was started on 10 mg twice a day and she weighs 25 lbs. She goes back for repeat ACTH stim tomorrow.

Marilynne in Atlanta

[molly muffin]

Sorry. My brain must have been having a cramp. I swear I read your first post twice and still managed not to take in the weight and dosage. Some days are like that.
That is a good start dose for Cushing's. We do always worry when there aren't a lot of symptoms.
You said still frequently urinating. Has there been any decrease? There was a trend for quite awhile where at around day 10 of treatment changes have started to be noted. Some do see symptoms get better in shorter times and others longer but I always think 10 is about average. Usually you retest between day 10 - 14 and see something before that.

Sharlene and Molly muffin

[Panda's mom]

It's been 11 days since starting trilostane and Panda's PU/PD symptoms have improved. She's definitely drinking less but I don't have exact amounts. The followup ACTH stim test was a bit odd: the pre-stim baseline was elevated at 17.1 ug/dl (originally 9.8 ug/dl) but the post-stim was down to 20.8 ug/dl (originally 28.9 ug/dl). The vet recommends staying with 10 mg bid of trilostane for the next month and rechecking the stim test. This seems reasonable, but I'm puzzled about that high pre-stim value -- it seems so out of line that I'm not sure how to interpret the post-stim one. Any thoughts on this? The test was supposedly done 4 hrs after her morning dose of trilostane.
Marilynne

[labblab]

That "pre" value is definitely oddly high, but maybe Panda was unusually stressed for some reason at the time of the baseline draw. The "post" value is still way above desired therapeutic range, but as long as you are seeing symptom improvement, I cannot argue with leaving the dose unchanged for another month. By that time, you will have a really good sense as to the effect of the 10 mg. so as to gauge the appropriateness/size of a dosing adjustment.

Marianne

[Panda's mom]

Thanks, Labblab:
Panda is definitely "high-strung" and it occurred to me that she might have been stressed having to wait an hour or two before her pre-stim was drawn. We've diagnosed this pretty early, so waiting isn't such a bad idea. Her symptoms are better, and that's what counts at this stage.
Marilynne

[molly muffin]

I don't think it would hurt to wait to up the dosage till after another stim test and see how that one looks. As long as her symptoms are good and she is doing well, waiting shouldn't be a problem at all. We have had it suggested to members to wait for 30 days and see where the cortisol is at anyhow before increasing as the same dose can continue to lower cortisol even at 30 days.

Sharlene and molly muffin