Well I am on pins and needles waiting to talk with my vet tomorrow.

The results of a blood panel on my 2yo GSD showed:

Elevated T4 ( 5.7, which is significant)
Slightly elevated eosinophils
Decreased CPK
All other values normal.

Anyone here have any knowledge, insight. I am searching the web and all that pops up is thyroid cancer and how uncommon high thyroid is in dogs.

She does not show clinical signs of hyperthyroid - yes she is very active but has incredible excercise tolerance (my dad gave up trying to wear her out after 2 hours two-ball), can settle, no polyuria, no heat stress, Normal heart rate and temp, she tends to put on weight and not loose weight on small qty of food. She is very muscular too. None of these are clinical hyperthyroid.

Well, I am beside myself and glad I bought VPI in Dec.

Nancy,
I am not sure about the thyroid question but the eosinophils if they are elevated means some sort of allergy to possibly wheat. Dont' know if there is a correlation between the two. You don't say what the normal T4 level should be?
Usually there are ranges and not just a number.

Just talked; elevated T4 is so rare in a dog and she has not ever seen it.

The ranges are 1-4 microgram/deciliter with Cyra being at 5.7; actually per journal article I found hyperthyroid dogs tend to be in the 5-7 range as the liver is very efficient at removing excess T4.

Vet recommends (and I will take her tonight) running Free T4 which is more sensitive and specific test, then sending her to a specialist if this value is elevated.

The diagnostic lab has a newsletter which does indicate spurious occurrences of high T4 that are not related to hyperthyroidism.

I am going to ask the veterinarian to perform a panel with check for antithyroglobulin antibody as high T4 can occur in a dog with HYPO thyroidism which makes it look like they are hyper thyroid. We'll see...but apparently eosinophils (which she is not concerned about as they are borderline high) can be elevated in certain thyroid conditions. I do know the linkage with allergy and parasites too so since she has sampled a smorgasboard of critter poo in the woods, I am going to have her checked for those too.

Hopefully the whole thing is just spurious test results; she (Cyra) is in excellent condition and fitness.

I would look more at the dogs behavior than any specific number. Our Giant is hypothyroid and on hormone. If we keep him in the "normal" range he is overly hyper and aggressive. We have to keep him at boderline hypo by the range, but it is correct for the dog.

Pay attention to the dog when there is little or no stimulation. If the dog is acting nervous and and can't seem to decide what to do with it's self then it may be hyper. The other issue is that the treatments for hyper-thyroidism would be permanent. It would not be reversable.

There ar 2 treatments. One is to surgicly remove the thyroid, and the other is treatment with Iodine-131. Both are going to remove the dogs ability to produce hormone at all and you will have to give thyroid hormone for the rest of the dogs life. It just isn't really feasible to try and do just enough to make the dog euthyroid and in people I have seen the thyroid actually gro back and they ended up hyper again.

I think my biggest concern is really the info from all my web research that the majority of hyperthyroidism in dogs is due to cancer.

Hypothyroid is defintely common and I have found some information on antithyroid antibodies formed due to Rabies vaccination -- these antibodies can falseley evevate total T4 so that a dog that appears hyperthryoid may be hypo. Also, the lab performing the diagnostic test for Total T4 has very nicely discussed the limitations of the test as a total predictor of thyroid function.

I guess I will wait for the test results and final analysis, as clinically the dog is perfect, full of all day long energy but able to live in our house without driving us crazy. She has no clinical symptoms of either condition.

Repeat test and additional tests came back normal.

Take home for anyone else is that total T4 alone is a very limited test and that it is, apparently, subject to spurious results.

Nancy,
Glad to hear everything turned out normal..
Karen