Difficult feline medicine cases (Proceedings)

Aug 01, 2011

Hyperaldosteronism is uncommon in dogs, but may be more common in cats than previously thought. Disorders of aldosterone deficiency have been recognized in combination with general adrenocortical insufficiency (Addison's disease), and will not be discussed here.

Clinical case one

A 13-year-old, castrated male domestic shorthair cat was presented for evaluation of acute onset of neurological signs. The owner complained that the cat was disoriented, uncoordinated, and was having trouble walking. The cat was kept as an indoor pet. All vaccinations were current. The diet consisted of a mixture of free-choice adult dry maintenance food and a small amount daily of canned food (a variety of flavors). Two other cats in the household were reported to be normal. The owner reported the cat's appetite had been mostly normal, but the owner thought the cat may have been drinking more than usual.

On physical examination, the cat was depressed and seemed ataxic. The body condition score was 3/9. There was pronounced cervical ventroflexion. The cat was mildly dehydrated, with a normal body temperature. The heart rate was 155 bpm, and there was a grade 2/6 systolic murmur, with a point of maximum intensity heard at the left sternal border. Abdominal palpation revealed a large urinary bladder, but no obvious abnormalities. The cat seemed to resent palpation of any part of the body. There was no palpable goiter

A neurological exam was done. The cat was depressed, but mentally appropriate, and irate. All cranial nerves were normal. Proprioception was normal. All spinal reflexes were intact, but were subjectively diminished. Based on the neurological findings, it was determined that rather than being ataxic or disoriented, the cat was profoundly weak.

According to the owner, the cat had never been unfriendly or uncooperative during veterinary visits in the past.

Some initial questions

     1. What are causes of weakness? (Consider neurological disease, metabolic disease, cardiopulmonary disease, muscle disease, orthopedic disease.)
     2. What is the significance of the heart murmur? Are there signs of heart failure?
     3. What is the significance of the heart rate?
     4. Should you be concerned about possible PU/PD at this point? What physical examination findings fit with this problem?
     5. Are you concerned about the cat's behavior?
     6. What is your initial problem list?

The initial workup included: urinalysis, serum chemistry profile, CBC, total T4, thoracic radiographs, and systolic blood pressure measurement.