Αποτελέσματα Αναζήτησης
When a dog suspected to have hypothyroidism has a low total T4 concentration, fT4 and/or TSH concentrations must be evaluated to help confirm or refute the diagnosis (TABLE 1). If the TSH concentration is high, hypothyroidism can be diagnosed.
Animals with primary hypothyroidism (by far the most common type) would be expected to have low serum T 4 or fT 4 concentrations with high endogenous TSH concentrations. However, serum TSH concentrations remain within the reference range in 20%–40% of dogs with confirmed hypothyroidism, so it has low sensitivity.
13 Ιουν 2024 · “We also measure thyroid stimulating hormone (TSH). If this is high in a dog with low T4 and fT4, we can be 100% certain the dog is hypothyroid,” she says.
Hence, true primary hypothyroidism will classically have a low T4 and a high TSH. ESS will have a low T4 and a normal to low TSH. Unfortunately, the current assays for canine TSH have poor sensitivity and between 13 and 38 % of hypothyroid dogs have TSH concentrations within the reference range.
Common clinical signs include lethargy, mental dullness, reluctance to exercise, cold intolerance and weight gain without polyphagia. Dermatological signs, especially endocrine alopecia, seborrhoea, scaly skin and superficial pyoderma, are present in 60% to 80% of hypothyroid dogs. Figure 1.
*rhTSH: recombinant human TSH: Dosages ranging from 50-100 µg have been used, however, in the presence of concurrent disease or drug administration, a dosage of 150 µg is recommended. Thyroid hormone concentrations vary opposite to age. Half of the dogs older than 6 years of age have lower TT4 serum values.
Definition. Hypothyroidism is an endocrinopathy caused by decreased production of thyroid hormone. Sponsor message; content continues afterward. Systems. Because most cells in the body are affected by thyroid hormone, hypothyroidism can affect most organs. Common signs are related to the dermatologic system and decreased metabolic rate.
