New Member - Kyro

[kyro]

Hi Marianne,

Thank you for getting back to me!

When you say his results are't looking too bad I am a little confused. His first test results showed numbers of 10.1 when he arrived, 2.2 at the 4 hour mark and then 4.2 at the 8 hour mark. Now his new results were 6.8 when he arrived and then 10.1 an hour later. We were told his numbers needed to be below 1.4. Is this incorrect? I was thinking we were way off on getting things controlled but you are saying a possible acceptable number could be around 9. Is it because they were 2 different tests potentially?

I apologize on the photos for the test results, you should be able to see them now!

[labblab]

Yes indeed, I can now see the new results -- thanks so much!

And yes, I believe we're talking about results from two entirely different tests, and that explains the discrepancy in the desired numbers. Your printed lab results are a bit odd, in that multiple cortisol levels are given but without any label as to the overall test that was being performed. So I'm making certain assumptions based upon our typical experience here.

Cortisol levels taken at baseline, then four hours later, and then eight hours later typically correspond with a specific type of diagnostic test: the Low Dose Dexamethasone Suppression Test (or LDDS). With this test, a baseline cortisol is first measured, and then the two subsequent levels are taken after a dose of dexamethasone has been administered. With this test, a dog without Cushing's should register a value less than 1.4 ug/dL at the 8-hour mark. If the cortisol level is higher than that, it means that the dog's adrenal function is so "overactive" that it has broken through the suppressive effect, and that result is consistent with Cushing's. Furthermore, depending upon the pattern of both the 4-hour and 8-hour results, you can draw conclusions as to whether the dog likely suffers from a pituitary rather than an adrenal tumor. In Kyro's case, his results were indeed consistent with the pituitary form of the disease.

Now, moving forward, a different test is used for monitoring treatment: the ACTH stimulation test. This test involves first taking a resting cortisol level, then injecting a *stimulating* agent and then testing the cortisol once again an hour later. FYI, the ACTH can also be used for diagnostic purposes, too, in addition to the LDDS. But the LDDS is solely designed to be a diagnostic test, whereas the ACTH is also used for monitoring treatment. So from this point onward, it will be the ACTH that will be given to monitor Kyro's response to the Vetoryl.

The norms that you are looking for are totally different for the two tests. In addition to the fact that your printed labsheets don't specify the types of test that were given, they also only give the normal baseline cortisol range for a dog who doesn't have Cushing's for every single cortisol level that was tested. And that is odd, for the reasons I gave above: the normal or desired testing ranges vary dramatically for the different cortisol levels taken on these two specific tests.

However, assuming I'm correct that the results on your labsheets were indeed for, first, a diagnostic LDDS test and then secondly, for a monitoring ACTH test, I'm going to give you a link to a technical brochure published by Dechra, the maker of Vetoryl. You'll see there the desired monitoring ACTH cortisol range for a dog being treated with Vetoryl. And that's where the upper limit of approx. 9 ug/dL on the post-ACTH reading comes in. Let me know if you have trouble downloading this brochure, because there are tons of other places where this same info is provided. I just like this particular link because it includes the U.S. Product Insert for Vetoryl, brief descriptions of the tests, as well as the monitoring ACTH flowchart. So do look this over, and then we can talk over any further questions.

https://www.dechra.us/Files/Files/Su...US-046-TEC.pdf

Marianne