Unfortunately many vets don't recognize
that a normal sodium and potassium level don't rule out Addison's.
I assume your vet is planning to determine whether your dog has Atypical or
Secondary Addison's at this point. The difference is where the problem
originates. With Secondary AD, it is the failure of the pituitary to secrete
ACTH (which tells the adrenals to work) that causes the problem. With
Atypical Addison's, the pituitary is working fine - it's the adrenals that
fail to work properly. They can tell which is which by measuring the levels
of ACTH in the body.
It is rather an academic point, since the treatment is the same
regardless - replace the glucocorticoids that the adrenals are failing to
produce. However, if the adrenals are not working properly, then there is a
greater chance that it will eventually turn into Primary Addison's. Primary
AD means that another zone in the adrenals also fails and no longer secretes
mineralocorticoids, which is what controls the sodium and potassium levels in
the body.
However, we have dogs on the list who started out Atypical and quickly
progressed to Primary and we also have dogs who are Atypical and have stayed
that way for years. I am unaware of any certainty in predicting which cases
will progress to full-blown AD. However, simply monitoring the serum sodium
and potassium levels will warn you if he begins to progress to Primary and
needs supplemental mineralocorticoids.
Anyway, you are right to be happy that it's Addison's and not something
untreatable. Once you get the right level of medications, you should find
your "old" dog is back. My Standard Poodle Cosette lived with Addison's for 8 of
her 9 years and had a wonderful life including Obedience and Agility trials,
tracking, Therapy dog visits and lots of retrieving those critters that she
hunted down on her own.
(courtesy Mary Ann)
Canine Addison's Disease FAQ