Quiz: Diagnosing Hypothyroidism in Dogs & Cats
Ed Shelton, BVM, BVS, PGDip (VCP), MRCVS, Royal Veterinary College, Hertfordshire, United Kingdom
Rebecca Geddes, MA, VetMB, MVetMed, PhD, DACVIM (Small Animal), FHEA, MRCVS , Royal Veterinary College, Hertfordshire, United Kingdom
Image courtesy of Chris Scudder, BVSc, MVetMed, PhD, DACVIM-SAIM, DECVIM-CA, MRCVS
In dogs, the most common cause of hypothyroidism is primary dysfunction of the thyroid gland caused by immune-mediated lymphocytic thyroiditis or idiopathic thyroid gland atrophy.1 In cats, the most common cause is iatrogenic, typically as a complication of treatment for hyperthyroidism.2,3
Definitive diagnosis can be challenging. Clinical suspicion based on patient history, physical examination, and clinicopathologic abnormalities should be high before thyroid function testing is initiated. Understanding the challenges of interpreting test results is important.