Hello again! I’m sorry it’s taken me so long to get back here, but Leslie has done a magnificent job of covering the bases. I totally agree with everything she’s written; Cushing’s does not seem very likely to me right now, either. I believe I’d also hold off on more involved testing until/unless more symptoms or abnormalities emerge that are consistent with the disease.

As Leslie has written, a resting blood cortisol level doesn’t mean much, diagnostically. However, if you do want to move forward with a bit more testing now, either the ACTH stimulation test or the Low Dose Dexamethasone Suppression test (LDDS) are the two diagnostic blood tests that would be more informative in that regard. There is one alternative urine test that you might consider first, however. I just wrote about it a few days ago in a reply to another member:

Hi again! There is one other alternative “gateway” test that you could consider. It’s called the UC:CR, or urine cortisol to creatinine ratio. We’ve been told that the best method by which to conduct this test is for the owner to collect a urine sample at home on three successive mornings, pool the samples together, and then take them to the vet for analysis. The samples should be collected with the least amount of stress involved as possible. This is why they should be collected at home and *not* at the vet’s office. If the ratio comes back within the normal range, Cushing’s can pretty much be ruled out definitively. If it shows an elevated proportion of cortisol, then Cushing’s is a possibility, but not proven, and you’d then still have to advance to either the LDDS or ACTH. However, I did want to offer this test to you as an additional possibility. It’s likely much less expensive than the LDDS or ACTH if it rules out Cushing’s, but it would be an added expense if you have to move on to the LDDS or ACTH in addition.

However, it’s just a thought, and here’s a link that explains it in more detail. One note: the link only references collecting a single urine sample for analysis. As mentioned above, we’ve been told by experts that a pooled sample from three mornings is more accurate.

https://vcahospitals.com/know-your-pet/urine-cortisol

Marianne
As you continue to think things over, do feel free to keep any questions coming.
Marianne