Canine hypothyroidism: avoiding over diagnosing the condition

In Pract. Mar 2022;44(2):68-75. 22 Refs

Susanna Spence¹

¹ North Downs Specialist Referrals, Bletchingley RH1 4QP, UK.

Author Abstract

Background: Hypothyroidism is one of the most commonly treated endocrine disorders in dogs; however, the diagnosis of this condition can be challenging, potentially leading to misdiagnosis. The clinical signs of hypothyroidism are vague and non-specific, as are the routine haematological and biochemical changes. When assessing the thyroid axis, the classical finding of decreased total thyroxine and increased thyroid-stimulating hormone is highly specific for the diagnosis of hypothyroidism, but has less good sensitivity. Although numerous other tests are available, a basic understanding of thyroid gland physiology and thyroid test methodology is needed to be able to use each test and interpret the results correctly.

Aim of the article: This article discusses how to confidently diagnose the condition, explaining how clinicians need to consider the clinical signs, routine clinicopathological changes and thyroid hormone concentrations together, rather than in isolation.

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