Question:

>The Orthopedic Foundation for Animals (OFA) is now offering a Thyroid >Registry. The information below is reprinted with permission. It is by >Ray Nachreiner, DVM, PhD, and is fully copyrighted. Feel free to e-mail >me with questions, but I may not be able to anwer them . This is part >2 of 2.

<snip> >Positive idiopathic hypothyroidism >  FT4D, < 8pmol/L >  cTSH, > 40mU/L >  TgAA, Negative

Ok, so autoimmune thyroiditis is inheritable and has genetic markers as stated in the first post. And you probably already know your=  dog has it if it is already on medication, and you shouldn’t be breeding it. But the post doesn’t say what Positive idiopathic hypo= thyroidism means to breeding stock. If you are testing to determine breeding stock, but there are no symptoms and the dog is not on = medication, what would a result in the last category mean genetically? Do they really know? julie (who has gotten conflicting and opposite results from two different labs on the same blood sample…)

Response:

> >Positive idiopathic hypothyroidism >  FT4D, < 8pmol/L >  cTSH, > 40mU/L >  TgAA, Negative > Ok, so autoimmune thyroiditis is inheritable and has genetic markers as stated in the first post. And you probably already know your dog has it if it is alread > Do they really know? > julie > (who has gotten conflicting and opposite results from two different labs on the same blood sample…)

I followed up to Julie in a private mail about her question, but in case anyone else is wondering……"they" may know, but frankly I do not . I posted the thyroid info for OFA because I knew this group would find it interesting! However, my own knowledge of hypothyroid is limited, and I don’t know the difference between idiopathic and autoimmune. If someone out there would care to enlighten both of us, I would appreciate it! Robin, Jasper and Dreamer (my opinions are my own!) Doberman page: http://www.hsc.missouri.edu/people/robin/rjntp.html Abby’s rescue page: http://www.hsc.missouri.edu/people/robin/abby.html

Response:

The Orthopedic Foundation for Animals (OFA) is now offering a Thyroid Registry. The information below is reprinted with permission. It is by Ray Nachreiner, DVM, PhD, and is fully copyrighted. Feel free to e-mail me with questions, but I may not be able to anwer them . This is part 2 of 2. CLASSIFICATION The method for classifying the thyroid status will be accomplished using state of the art assay methodology. Indices of thyroiditis: a. Free T4 by dialysis (FT4D). This procedure is considered to be the "gold standard" for assessment of the thyroid’s production and cellular availability of thyroxine. b. Canine Thyroid Stimulating Hormone (cTSH). This procedure helps determine the site of the lesion in cases of hypothyroidism. In autoimmune thyroiditis the lesion is at the level of the thyroid and the pituitary gland functions normally. TSH is expected to be abnormally elevated in dogs with thyroid atrophy from autoimmune thyroiditis c. Thyroglobulin Autoantibodies (TgAA). This procedure is an indication of the presence of the autoimmune process in the dog’s thyroid. CERTIFICATION Normal:   FT4D, 8-30pmol/L   cTSH, 7-40 mU/L   TgAA, Negative Positive advanced autoimmune thyroiditis   FT4D, < 8pmol/L   cTSH, > 40mU/L   TgAA, Positive Positive compensating autoimmune thyroiditis   FT4D, 8-30 pmol/L   cTSH, 10-100mU/L   TgAA, Positive Positive idiopathic hypothyroidism   FT4D, < 8pmol/L   cTSH, > 40mU/L   TgAA, Negative LABORATORY CERTIFICATION The laboratory certification process will include quality control,quality assurance and reagent certification. Laboratories may apply and if successful will be approved to perform analyses for OFA thyroid certification. A site visit by a qualified veterinary endocrinologist chosen by OFA will be required and continued quality assurance and quality control will be necessary to maintain certification. Fully certified status can be obtained by passing the site visit and passing the results of the first OFA quality assurance assay result test. The approved laboratory must be contacted for the appropriate submission forms, sample handling procedures and laboratory service fee before collecting the sample. Currently, samples may be submitted to: Animal Health Diagnostic Laboratory Endocrine Diagnostic Section PO Box 30078 Lansing, MI  48909