A friend has a dog that's having some major medical trouble.

Initially the problem was some sort of lump/growth on the back of her thigh - one vet insisted this was a bed sore but as the dog is always on the go (goes to work with the owner who's a dog walker), that's not the case.  Given many steroids to try and bring it down to no avail.

The owner changed vets - no more steroids and the lump is much better.  But, the dog now appears to have Cushings - textbook look, with the pot belly and hair loss.  She looks awful - I saw her only a couple of weeks ago (this was quite some time after the change of vet) and she had full coat, lively, and looked fine.  Now, she is nearly bald with just whispy hairs left, and has the pot belly.

She's been checked twice for Cushings through the blood tests (proper stimulation tests) and has also had an ultrasound to rule out internal adrenal tumours.

Any ideas?  She's had medical trouble most of her life - had her windpipe replaced when she was a year old, has trouble with reflux from excess acid and she also reacted to her microchip and has chronic peritonitis at the implant site (it was removed years ago though).  So she's has steroids for the peritonitis for years, however these were stopped before the change of vet too.  The Cushings-esque symptoms have come on I'd say in the last month or so - stopping of steroids was at least a couple of months ago.