There’s another misunderstanding called atypical Cushing’s disease. I’m convinced that a dog diagnosed with Cushing’s without corresponding symptoms doesn’t have the disease.

While there is such a thing as atypical Cushing’s disease, it’s not what most people think it is. About ten years ago, veterinarians at the Royal Veterinary College in England observed dogs that had all the classical signs of Cushing’s disease. These dogs:

Were drinking a lot of water
Were urinating a lot
Had urine specific gravities below 1.025
Had pot-bellied appearances
Showed muscle wasting
Had weakness in the hind legs
Had ravenous appetites and excessive panting

But their Low Dose Dexamethasone Suppression test and ACTH Stimulation tests came back normal.

And they all got better on Lysodren.

So these vets did some excellent research. They found that every dog had an elevated sex steroid called 17-hydroxyprogesterone. This was thought to be a marker or possibly the cause of all the symptoms of Cushing’s disease. Yes, these dogs with atypical Cushing’s disease had all the symptoms of the disease. But in the end a different hormone was causing these symptoms.