Canine hypothyroidism: avoiding over diagnosing the condition

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.

Spinal Epidural Lipomatosis Secondary to Hypothyroidism in a Siberian Husky Dog

“…In this case, the patient showed typical clinical signs of hypothyroidism including severe lethargy, symmetrical alopecia and dull hair. Although it may have been affected by the MPSS injection, two weeks have passed since the last injection, and considering that TSH was also elevated, the results of the thyroid panel showed that hypothyroidism was more suspected than drug interaction or Non-thyroidal illness (17). In addition, considering that the patient responded well to levothyroxine treatment, we diagnosed that the patient had hypothyroidism.…”

Retrospective Evaluation of Gastrointestinal Signs in Hypothyroid Dogs

“…Hypothyroidism is one of the main endocrine disorders in dogs [ 1 ]. Lymphocytic thyroiditis and idiopathic thyroid atrophy are the most common causes of this condition, and clinical signs appear following the destruction of 75% of glandular parenchyma [ 1 ].…”

“…Lymphocytic thyroiditis and idiopathic thyroid atrophy are the most common causes of this condition, and clinical signs appear following the destruction of 75% of glandular parenchyma [ 1 ]. The most common clinical signs of hypothyroidism are related to decreased metabolic rate and dermatological changes, while less frequent but well-documented clinical manifestations include neurological, cardiovascular, and reproductive abnormalities [ 1 ]. In both human and veterinary medicine, hypothyroidism is a well-known cause of alteration of multiple gastrointestinal processes [ 1 , 2 , 3 ].…”

“…The most common clinical signs of hypothyroidism are related to decreased metabolic rate and dermatological changes, while less frequent but well-documented clinical manifestations include neurological, cardiovascular, and reproductive abnormalities [ 1 ]. In both human and veterinary medicine, hypothyroidism is a well-known cause of alteration of multiple gastrointestinal processes [ 1 , 2 , 3 ]. Patients can suffer mainly from constipation [ 3 ] as a result of abnormal peristalsis [ 4 ] due to alterations of hormonal receptors and neuromuscular disorders using mucopolysaccharides infiltration.…”

“…In humans, most of the gastrointestinal alterations often resolve with treatment of the underlying thyroid disease, thus confirming the hypothesis of a causal relationship [ 3 , 17 , 18 , 19 ]. In veterinary medicine, although often reported in textbooks [ 20 ], information regarding GI signs in hypo-T dogs is scarce [ 1 , 21 , 22 , 23 , 24 , 25 , 26 ]. An old and isolated experimental study demonstrated a decreased electrical and mechanical activity of the stomach and jejunum in four Labrador retrievers that underwent complete thyroidectomy [ 21 ].…”