Tertiary Hypothyroidism in a Dog
February 2007
in “
Irish Veterinary Journal
”
TLDR A dog with a pituitary tumor developed tertiary hypothyroidism, improved with treatment, but was later euthanized due to neurological issues.
A 9-year-old male Labrador was diagnosed with tertiary hypothyroidism, a condition not previously reported in dogs, following treatment for pituitary-dependent hyperadrenocorticism. The dog exhibited symptoms such as weight gain, seborrhoea, and alopecia, with tests showing low thyroxine levels and a pituitary mass. Levothyroxine treatment improved dermatological issues and cholesterol levels, but the dog was euthanized due to neurological symptoms caused by a pituitary adenoma affecting the hypothalamus. This case highlighted the diagnostic challenges of central hypothyroidism and the importance of distinguishing between secondary and tertiary forms.