Autoimmune Thyroiditis in Dogs

Category
Hormonal
Breeds documented
14
Published sources
8

Overview

The immune system can mistakenly attack the thyroid gland, which helps regulate how the body uses energy. Damage may gradually reduce the gland's hormone production and lead to hypothyroidism, meaning too little thyroid hormone. Some dogs have signs of this immune activity while their hormone levels remain normal. A positive antibody result therefore does not automatically mean a dog already has an underactive thyroid.

Signs to watch for

  • Weight gain without eating more
  • Less energy and willingness to exercise
  • Thinning hair or a dry coat
  • Seeking warm places more often

Signs often appear at 2 to 5 years; thyroid inflammation can begin before obvious illness.

When to get help Book a vet visit for unexplained weight gain, low energy or coat changes.

Diagnosis and tests

Vets check thyroid hormone levels together with antibodies that can signal an immune attack on the gland. The OFA thyroid panel measures free thyroid hormone, thyroid-stimulating hormone and antibodies to thyroglobulin, a thyroid protein. Antibodies show immune activity, but do not measure how well the gland works. Repeat testing may be needed because results can change over time.

Breeds with documented risk

14 breeds

By breed size
  • 4 Small
  • 4 Medium
  • 5 Large
  • 1 Giant

Most popular breeds on this list

All 14 breeds, A to Z

Inheritance

  • Not yet known

    None of the sources we use states how this is inherited in dogs yet.

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.

Sources

  1. merckvetmanual.com
  2. merckvetmanual.com
  3. ofa.org
  4. frontiersin.org
  5. Giant Schnauzer: pubmed.ncbi.nlm.nih.gov
  6. Great Dane: cliniciansbrief.com
  7. Miniature Aussiedoodle: petmd.com
  8. Puggle: petmd.com