Just a general suggestion instead of anti-biotics you could try CS. I did this for my dog for other sicknesses.
Our dog over the years sometimes seems to have cushings, but since I don't want to give him the poison treatment, we never did the last test. I did find out that he had low thyroid, put him on a drop of Lugol'sIodine a day and he is a changed dog.
Here is discussion from Trapper's forum about CS
I can't find the link but somewhere else he suggested to take the Iodine with oil he thought it might help when you also give CS. I will keep looking for the post.
Since I don't remember the details I put a drop of Iodine on his hamburger I figured that is fat too.
Did you at least try to search adrenals on all forums and the VWT forum, sometimes there are pet questions on other forums too.
Sorry I can't help you more. Good to see you around.