Hyperthyroidism is a disease frequent with old cats. It generally affect animals of over 8 years.
The thyroid gland is located in the neck of the animal, on either side of the trachea. The disease is caused by a tumor, usually benign, of the thyroid gland causing hormone secretion in too large quantities. This gland uses food iodine to produce thyroid hormones that help regulate important body functions including: metabolism, body temperature, blood pressure, heart rate, gastrointestinal function.
Since thyroid hormones have a profound effect on the metabolism and function of several organs, when produced in large quantities, they increase the work that these organs must perform, making then numerous clinical signs.
What is most striking, is primarily a significant weight loss despite a voracious appetite. Behavioral changes can also be recorded. Indeed, the animal may be more active, vocalizing, be more aggressive, etc. In the digestive system, we often see soft stools and frequent vomiting. In some cases, the coat and skin will be in poor condition. Finally, the cat can consume more water than normal and thus urinating in larger amounts or more frequently.
To diagnose this disease, it is first necessary that a veterinarian examines the cat completely. The veterinarian will then note any weight loss and sometimes he can feel nodules (lumps) at the thyroid. Auscultation show a high heart rate, often with a heart murmur. Subsequently, a full blood work must be done, in order to confirm the disease. The test will detect the level of hormone in the blood of the animal, and also assess the extent of the problem by evaluating other vital organs. Further cardiac evaluation may have to be made, by chest x-rays and a measure of blood pressure.
The most common treatments are implemented are medication for life or therapeutic food designed specifically for this disease. There is also surgical or radioactive idodine treatment.
If you have a cat aged that’s about 7 years or older who present some of these changes, please contact the Ste-Rose Veterinary Hospital to get an appointment for an examination and geriatric blood test.
Catherine Lapierre, Certified Veterinary Technician