Total T4 alone is often misleading
· Overdiagnoses hypothyroidism in the presence of non-thyroidal illness or use of certain drugs
· Underdiagnoses hyperthyroidism in cats or from thyroxine overdosage
· Inaccurately assesses adequacy of thyroxine therapy
· Fails to detect autoimmune thyroiditis
· Minimal testing is T4 + free T4, except thyroiditis will still not be detected
· For cats, but not dogs, cTSH can be helpful to identify concurrent hyperthyroidism and renal failure
Dr. W Jean Dodds is an international thyroid expert and leads the clinical research team at Hemopet’s Hemolife Diagnostics. Hypothyroidism is the most common endocrine disorder in dogs, and yet is one of the most challenging conditions to diagnose. Dr. Dodds strives to raise awareness for proper screening measures. For more in-depth information, please read her award-winning book, written with Diana Laverdure, The Canine Thyroid Epidemic: Answers You Need for Your Dog, (2011, Dog Wise).