Hyperthyroidism is an illness that occurs in the case of cats between the ages of 4 and 16 years, especially in those with an average age of 10 years. When it is detected in time, it can be treated, with very high chances of healing.
An interesting thing to underline is that cats have two thyroid glands or, more correctly, a thyroid gland composed of two thyroid lobes. They are located in the neck, lower larynx and play a vital role in regulating the level of hormone secretion. Thus, hyperthyroidism is a condition that is characterized by an excessive production of thyroid hormones which leads to an increase in the metabolic rate. You do not have to worry even if the thyroid gland is enlarged in size because these changes are benign, less than 2% of cases of hyperthyroidism in cats highlighting the existence of malignant tumors of the thyroid gland.
As mentioned before, if detected early, hyperthyroidism in cats is successfully treated. Therefore, it is important to know and identify the symptoms of this condition. A first clinical sign that shows that the cat may suffer from hyperthyroidism is weight loss caused by increased metabolic rate, beyond a normal or even exaggerated appetite. Appetite disappears only when the disease is very severe. In addition, water consumption is increased. High levels of thyroid hormones cause excessive thirst, much higher water consumption and, consequently, more frequent urination.
Also, another common symptom is agitation. Cats suffering from hyperthyroidism become very active and sometimes even aggressive. Due to hyperactivity, sleep problems can also be felt.
Fur can also be an indicator. In the case of many cats with hyperthyroidism, the fur looks messy because it does not clean it but it does not allow the owners to do so.
Greater attention should be paid to the heart rate. In the case of hyperthyroidism, it is much more accelerated, exceeding the level of 140-200 beats per minute, existing in the case of healthy cats.
The digestive system is also affected by the large amount of hormones, its functions changing and leading to symptoms such as vomiting and diarrhea.
Other symptoms that occur in cats with hyperthyroidism are breathing problems, fur loss, excessive claw growth and in the advanced stages of the disease fever and physical weakness.
The diagnosis is established by performing both a clinical examination and imaging tests, electrocardiography and laboratory tests (blood tests, urine tests). These tests are used to assess the general health of the cat but also to be able to anticipate any complications, especially those of a cardiac nature.
Hyperthyroidism can be treated by surgery or by the use of radioactive iodine or controlled with the help of medication and an appropriate diet.
The radioactive iodine is given as an injection and its role is to destroy the abnormal thyroid tissue, without affecting other organs. It does not require anesthesia but it is necessary to hospitalize for up to two weeks in a veterinary hospital authorized and specialized in performing radiotherapy. Subsequently, the need for daily drug treatment is eliminated.
Surgery involves removal of one or both of the affected thyroid glands and is effective in the vast majority of cases. However, given that cats with hyperthyroidism are over 10 years old, there may be some risks. If the cat is otherwise healthy and the tests do not reveal other conditions, whether related or not, these risks are minimal.
Before performing surgery called thyroidectomy, it is recommended that the cat undergo thyroid tissue scintigraphy to detect situations where the thyroid cells are in abnormal locations (ectopic thyroid tissue). Before and after the medical interview it is recommended to perform a drug treatment. The hospitalization may take one or two days. After returning home, the cat should regain normal behavior.
As for oral medication, metimazole blocks the overproduction of thyroid hormones. Given that he does not destroy the abnormal thyroid tissue, his administration is done throughout the cat’s life. It is called upon if the operation involves a high risk, especially in the case of very old cats. The effects of the treatment become visible in a few weeks. In order to detect any possible side effects, it is recommended to monitor the cat by performing the usual blood tests every 3-6 months.
Last but not least, Hill’s Prescription Diet y / d Feline is recommended for cats with hyperthyroidism. Research has shown that by controlling the level of iodine in the food, the body of the hyperthyroid cat has the possibility to resume its normal production of thyroid hormones. It is not a deficient diet in iodine but its level is controlled at 0.32 parts per million. The hormone level should return to normal within a period of 8-12 weeks.