Anti-triiodothyronine antibodies associated with hypothyroidism and lymphocytic thyroiditis in a dog
Chastain, C.B.; Young, D.W.; Kemppainen, R.J.
Journal of the American Veterinary Medical Association 194(4): 531-534
1989
ISSN/ISBN: 0003-1488 PMID: 2921203 Document Number: 346003
A 5-year-old spayed Shetland Sheepdog had clinical signs consistent with hypothyroidism. Laboratory findings, including subnormal serum T4 concentration, also were suggestive of hypothyroidism; however, the apparent serum T3 concentration, as determined by a solid phase assay, was extremely high. Thyroid scintigraphy showed ectopic radionuclide uptake in the neck and throid biopsy revealed lymphocytic thyroiditis. Determination of T3 autoantibody titres confirmed that the previously measured high serum T3 concentration was spuriously high because of autoantibodies to T3.