Differential Diagnosis For Hyperthyroidism In Cats

The cat s heart rate and blood pressure may also be checked.

Differential diagnosis for hyperthyroidism in cats.

During the physical exam your vet may notice heart murmurs an accelerated heart rate or a type of heart beat called a gallop rhythm your vet may palpitate your cat s throat to feel for an enlarged thyroid gland. Diagnosis of feline hyperthyroidism. If thyroid disease is a possibility your veterinarian will likely order a blood chemistry. Enlarged thyroid without clinical fht cats without clinical hyperthyroidism t4 within the reference interval but with enlarged thyroid gland s monitor clinical signs in these cats and repeat a serum t4 assay in 6 months.

The coat of affected cats may appear unkempt matted or greasy see figure 1. In cats the majority of anaemias are non regenerative in contrast to the dog. Most cats diagnosed with hyperthyroidism have benign non cancerous growths on their thyroid gland and are producing levels of the thyroid hormones t3 and t4 that are too high. Diagnosis a veterinarian who suspects a cat has a thyroid problem will conduct a physical examination and palpate the cat s neck area to check for an enlarged thyroid gland see figure 2.

A clinician can assign a cat to one of six diagnostic categories as described below and summarised on page 404. Presence of one or more clinical signs see clinical signs of feline hyperthyroidism increased serum total thyroxine t4 concentration. Some cats have malignant thyroid cancer but that s much rarer. Differential diagnoses for cats with clinical signs similar to hyperthyroidism should include diabetes mellitus gastrointestinal malabsorption or maldigestion neoplasia especially gastrointestinal lymphosarcoma chronic kidney disease ckd and parasitism.

There are in fact a growing number of cats with clinical signs of hyperthyroidism and palpably large thyroid glands whose baseline serum total thyroid hormone. Diagnosing hyperthyroidism in cats your vet will begin by asking you for a detailed history of your cat s signs and symptoms including litter box habits weight changes eating and drinking habits and amounts activity levels and changes in behavior moods. However up to 10 of all hyperthyroid cats and 40 of those with mild disease have serum t4 values within the reference range 1 2. Cat hyperthyroidism usually occurs in middle aged or geriatric cats.

However multiple causes of anaemia can be present concurrently. I will then turn to when we do dynamic thyroid function testing. Since the symptoms of feline hyperthyroidism could be similar to those. Hyperthyroidism may also cause vomiting diarrhea and hyperactivity.

Signs of hyperthyroidism in cats cats with hyperthyroidism often show some or all of the following signs. In this first blog post in this series of confirming the diagnosis of hyperthyroidism in cats i m going to discuss the use of serum thyroxine t4 concentrations to make a definitive diagnosis of hyperthyroidism in cats. The diagnosis of hyperthyroidism one of the most common disorders affecting elderly cats is usually straightforward and considered routine by most practitioners. In my next posts we will discuss the use of free t4 then look at the use of serum tsh measurements.

Nowadays however most cats suffering from hyperthyroidism tend to be diagnosed earlier and at a milder stage of the disease than those cats diagnosed 10 to 25 years ago.