Rj. Kemppainen et al., AUTOANTIBODIES TO TRIIODOTHYRONINE AND THYROXINE IN A GOLDEN RETRIEVER, The Journal of the American Animal Hospital Association, 32(3), 1996, pp. 195-198
A golden retriever presented with signs of hypothyroidism occurring in
conjunction with autoantibodies to both triiodothyronine (T-3) and th
yroxine (T-4) The autoantibodies caused the apparent concentrations of
total T-3, total T-4 and free T-4 by analog assay to be high. However
, free T-4 concentration was nondetectable when measured using a dialy
sis assay. The dog's clinical condition markedly improved in response
to L-thyroxine therapy and the free T-4 concentration by dialysis assa
y increased into the normal range. Thyroid hormone autoantibodies can
confuse the diagnostic evaluation for suspected hypothyroidism. In dog
s with autoantibodies to T-4 measurement of free T-4 by dialysis assay
is useful for both diagnostic and therapeutic monitoring purposes.