Nutritional nuggets for hyperthyroid cats

Laboratory tests generally include a urinalysis, serum chemistry profile, and serum T4 measurement. Most cats with hyperthyroidism will have elevated T4 concentrations. However, a small percentage will have concentrations within the normal range. Additional tests may be needed if hyperthyroidism is still strongly suspected. Diagnostic imaging (thoracic radiography, cardiac ultrasonography) and electrocardiography may also be beneficial in determining the scope of secondary disease conditions. It is also important to rule out concurrent disease processes, such as renal disease, as this is a common diagnosis in older cats. A study conducted by a pet food manufacturer to determine the effects of feeding an iodine-restricted diet to hyperthyroid cats with naturally occurring hyperthyroidism was recently conducted.1 The objective was to determine the maximum concentration of dietary iodine required to maintain normal serum total ? concentrations in hyperthyroid cats. The results of the yearlong study indicated that the use of a diet with severely restricted iodine concentrations could result in normalization of T4 concentrations in hyperthyroid cats. One hundred percent of the cats tested had normal total T4 concentrations when fed the lowest level of iodine (0.17 ppm). None of the cats in the study suffered any adverse reactions as a result of eating the iodine-restricted food. Hyperthyroidism is the most commonly diagnosed endocrinopathy in middle-aged and older cats. Animals with hyperthyroidism are in a hypermetabolic state, and their body's energy expenditure is markedly increased. They are burning calories faster than they can replenish them with their daily meals and may need to be fed in excess of their basal MER to be able to regain and maintain a good body condition score. Patients being treated for hyperthyroidism need to be closely monitored to ensure that their weight and body condition scores do not decline. Clients should know the signs of malnutrition, be able to assign a body condition score, and check their cat's weight regularly at home. If the cat's hyperthyroidism is left untreated, death from starvation (or other concurrent disease process) may occur. If the animal has a concurrent disease process such as chronic renal insufficiency, which may be unmasked after the hyperthyroidism has been diagnosed, the hyperthyroid cat's health may be further compromised, and its dietary needs more complicated. Perhaps the most important thing to remembe