French bulldog w calcinosis cutis - Qs on Cushings diagnosis & treatment

Thanks for the advice, Renee! I'll post the LDDS results as soon as I receive them.

Good info, thanks Renee.

Here are Lola's LDDS results, indicating Cushing's:
Cortisol Sample 1 (Pre) 2.0 ug/dL (Reference range = 1.0-5.0)
Cortisol Sample 2 Dex (4hrs) <0.7 ug/dL (Reference range = 0.0-1.4)
Cortisol Sample 3 Dex (8hrs) 2.5 ug/dL (Reference range = 0.0-1.4) HIGH

The lab results also said the following:
If the 8hr post dex. cortisol level is greater than 1.4 ug/dl, the following can be used to differentiate pituitary dependent hyperadrenocorticism (PDH) from an adrenal tumor:
1. Cortisol level less than 1.4 ug/dl 4hrs post-dex is consistent with PDH.
2. Cortisol level less than half the baseline level at either 4 or 8 hours post-dex is consistent with PDH.

The wording is confusing, but based on the above, it sounds like it is a pituitary-caused case of Cushing's. Given this, is it still worth getting an ultrasound?

My vet is inclined to go with vetoryl over lysodren given the potential damage to the adrenals with lysodren...

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My vet is inclined to go with vetoryl over lysodren given the potential damage to the adrenals with lysodren...

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You and your vet need to be aware of the fact that Vetoryl can and does cause the exact same damage to the adrenals as Lysodren. They can both cause permanent Addison's and even death - they simply work differently and stay in the body differing lengths of time. Make sure your vet is up to date on all the changes with Vetoryl since the drug insert was printed, too. ;)

Thanks, Squirt's mom, good to know.

FYI, my dog is about 22/23 pounds - and I've been reading here low and slow is the best way to start either medication. Any thoughts on suggested initial dosing for either medication?

Leslie is correct - while vetoryl does not erode the adrenals in the same fashion as lysodren, it can and has caused spontaneous addison's.

If your pup is 22-23 pounds, I would start at a max of 20mg vetoryl, and give it at least 30 days before adjusting the dose (if needed).

You're doing good!

As to your question re the ultrasound --- my personal opinion, and what I did, was to wait. I knew she (Tobey) had cushings, and I knew what treatment I was going with (vetoryl).... so, I saved the money and delayed doing imaging until later into treatment. We ended up getting a CT, and it confirmed PDH.

Great, thank you!

After starting the vetoryl, my vet wants to run the ACTH tests after 1, 3 and 6 months to see how Lola is doing. Do you think we need to be testing more frequently than that?

The "start low and go slow" applies more to Vetoryl (Trilostane) than it does Lysodren. Lyso is loaded at 50mg/kg/day and maintenance is 25-50mg/kg/week. There is no loading nor maintenance phase with Vetoryl - you start giving it and give every day. Vetoryl is often more expensive to use because it often requires frequent dose changes and with each dose change, the ACTH monitoring schedule starts all over.

Got it!

I'll be sure to let you all know what we end up going with for Lola and how she and the CC are progressing with the treatment.

Thanks again, all!

I "second" Renee's recommendation that you start off with 20 mg. if you are opting to treat with brandname Vetoryl. With that dosage strength, you could easily have the option of giving the full 20 mg. once daily in the morning or instead 10 mg. twice daily. There are pros-and-cons with both dosing options, and different specialists have different preferences in that regard so there is really no right or wrong approach. If once daily dosing fits more conveniently into your daily schedule, I'd see no reason to start out differently. Down the road, if it turns out that you are seeing a rebound in symptoms later in the day, you may want to try giving twice daily dosing a try.

As far as monitoring ACTH testing, Dechra's official published protocol is to conduct an initial test at the 10-14 day mark. Then, as long as the cortisol level has not dropped too low, the recommendation is to remain at the same dosing level until the one-month mark. This is because cortisol levels have a tendency to continue to drift downward during the early days of treatment, even when the dose remains unchanged. In this way, you have a better idea as to the maximal effect of that initial dose prior to making an increase.

We are finding that some specialists are holding off until the one-month mark to perform the first full ACTH test (omitting that first two-week test). I can only speculate that it may be because they don't intend to increase the dose until a month has passed, regardless. And as long as the dog is behaving normally and looking well, they are assuming that the cortisol has not dropped too low. One "twist" I have sometimes seen added is to perform a simple baseline or "resting" cortisol at that initial two-week mark. This involves only a single blood draw and is less expensive than a full ACTH. While not an accurate indicator alone of the need for a dosing increase, a baseline cortisol can give you some added reassurance that cortisol is not dropping too low (which is the issue that is most important for a dog's safety). As long as a baseline cortisol is higher than 2.0 ug/dl, there is some reassurance that the dog is not bordering on an Addisonian condition.

Of course, all bets are off if a dog is acting unwell at any time. Then the monitoring testing becomes a necessity.

It is true that we have seen many dogs here who have required periodic and even frequent tweaking of their Vetoryl doses. But we have also seen dogs taking Lysodren who have experienced lengthy loading periods or Addisonian scares that have also required a great deal of monitoring. We have seen very large dogs who ended up taking relatively small doses of Vetoryl, and vice versa (small dogs requiring larger doses). So in advance, I think it's hard to say which drug would end up being more expensive for any given dog. There are many times when a crystal ball would sure come in handy! :o

Marianne