HI X,
I'll try to answer your 2 big questions.
 
1 Diabetes: Yes ferrets can develop high blood glucose if they are on
pediapred, or after insulinoma surgery.  Both are rare but they do happen.
 
Since she has not had a previous insulinoma problem it is likely that
the pred is causing the high blood glucose.  Hopefully when you stop the
pediapred her glucose will come down to the normal range.  If the glucose
remains elevated after you stop the pred then it is time to start insulin
therapy.  I would not wean her off pred.  I would simply stop it ASAP.
 
2 Adrenal: Since she is showing signs of adrenal gland disease again it is
likely that her right adrenal gland has "regrown."  Since you did not have
to give pred and/or Percorten after the adrenal surgery it is unlikely the
both glands were completely removed, and it is usually the right gland
that is the hard one to get completely out.  Yes, I would suggest Lupron
or another adrenal gland surgery.  Yes, the adrenal gland(s) can regrow
quickly.
 
Hope that helps,
Jerry Murray, DVM
[Posted in FML issue 3665]