Thyroid Blood Tests for Cats

Thyroid blood tests are a useful diagnostic test conducted to detect thyroid disorders in cats. The thyroid gland is situated at the base of the cat's neck and secretes thyroid hormones necessary for normal functioning of the body. Over secretion of the thyroid hormone or under secretion causes various health concerns that have to be diagnosed and treated accordingly. Hyperthyroidism and hypothyroidism are the two types of thyroid problems associated with the thyroid gland. Although hypothyroidism is unusual in cats, most pets suffer from hyperthyroidism associated with adenomas. Pet owners should notice the symptoms of thyroid dysfunction and seek medical help to initiate early treatment.

Hyperthyroidism in Cats

Although feline hyperthyroidism is not necessarily caused due to malignant cell growth around the thyroid gland, cats often develop benign growths in the thyroid gland that are tested for malignancy. This condition can occur in pets of all breeds. Older cats are more susceptible to hyperthyroidism along with other medical concerns.

Symptoms of Thyroid Disorders in Pets Include:

  • Weight loss
  • Lack of appetite or increased appetite
  • Polyuria and polydipsia
  • Behavior changes
  • Lethargy

Thyroid Blood Tests

The severity and type of thyroid disease present is related to the type of symptoms exhibited. The vet will evaluate the clinical symptoms exhibited and consider the pet's medical history. After physical examination of the thyroid gland through palpation, the vet will perform various blood tests to determine abnormalities in the amount of thyroid hormones present in the blood. Blood tests will determine the amount of T3 and T4 present. Elevated levels of thyroid hormones are associated with feline hyperthyroidism.

Often, pets may have normal levels of thyroid hormones in the blood during testing. In order to obtain a definite diagnosis, the vet may then perform a diagnostic test known as free t4 test. Apart from these measures, blood tests may also reveal higher levels of red and white blood cells. These elevated levels are indicators of underlying health conditions such as liver disease. Since the level of the thyroid hormone thyroxine varies during the day, the vet may recommend re-testing the pet to confirm thyroid dysfunction.

Other Diagnostic Tests

Apart from blood tests used to detect thyroid gland function, the vet will perform a scan to detect the presence of adenomas or abnormalities of the thyroid gland. Additional diagnostic tests are also necessary to rule out health concerns such as diabetes mellitus, renal disease and liver disorders. Complete blood count tests, ultrasounds and urine analysis may be performed if necessary.

Treatment for Thyroid Disorders in Cats

Since hypothyroidism is rare, cats suffering from hyperthyroidism are administered medications to regulate hormone secretion. The most commonly used drug to alter hyperthyroidism is methimazole. If the thyroid gland is severely affected due to the presence of abnormal cells, surgical intervention is necessary. Other treatment options include radioactive iodine treatment and chemical ablation. If hyperthyroidism is associated with underlying health concerns, it's important to treat the primary cause to eliminate the symptoms.

Pets suffering from thyroid problems should be administered prescribed medication on time. It's also important to follow up with vet checks to check the levels of thyroid hormones present in the blood.