Visiting Vet: Aslan in his old age

Just like with humans, there are certain diseases that increase as felines age.

It's important to not dismiss an elder cat's problems as just old age. —Jonas Jaeken

When I was in veterinary school, long, long ago, I had a professor who used to say, “Old age is not a disease.” What he meant was that when evaluating senior animals who weren’t doing well, we shouldn’t just dismiss it as “old age.” We should look for what system in the body was no longer working properly. Kidney failure, heart failure, arthritis, cancer. Not just to write off the elderly, but to figure out how we could fix them, or at least improve their quality of life. I have repeated this line to many clients over the past 40 years, encouraging them not to give up on their geriatric pets. But I have also come to appreciate another adage: “Just because we can do something doesn’t mean we should.”

Aslan is an elderly cat, somewhere between 13 and 18 years old, we don’t know for sure. A completely indoor cat and the only pet, he has been a happy, healthy boy all his life. He didn’t get to the veterinarian as routinely as we advise, but his owner always had him seen on the rare occasions when he wasn’t feeling well. When their regular veterinarian retired, she wasn’t too worried. Aslan was a hale and hearty fellow. 

Until he wasn’t. Aslan had always had a good appetite. In fact, like many indoor cats, he had been significantly overweight most of his life. Until a few months ago. Recently he had been eating less, and gradually losing weight. His owner brought him to an Island veterinarian through our system of rotating urgent care. The doctor did a thorough exam and blood work. Aslan’s liver, kidney, and thyroid function, blood sugar, and electrolytes were all within normal limits. He was not anemic. He did not have a fever. The only abnormal finding was moderate dental disease, not uncommon in elderly cats. They treated Aslan with antibiotics, fluids, and pain medication, and sent him on his way with the suggestion to consider dental cleaning under anesthesia. His owner was concerned about anesthesia risks, and opted to see if he improved after this initial treatment.

Six weeks later, Aslan came to see me, again through our rotating urgent care system. He hadn’t eaten at all for two days, was drinking huge amounts of water, and had vomiting and diarrhea. I had seen Aslan once, four years ago. At that time he had been obese, weighing 16 pounds. Now he was down to a “healthy” 8½ pounds, but he obviously was not “healthy.” I couldn’t find an obvious cause for this dramatic weight loss. His teeth looked fairly typical for an old cat, and unlikely to be implicated in these new gastrointestinal signs. “I know he just had lab work done recently,” I said, “but I’d like to start by repeating those tests.” Many old cats with a history like Aslan’s have diabetes, hyperthyroidism, or kidney or liver disease. His owner readily agreed. An hour later I was staring at Aslan’s repeated blood tests. Everything still looked completely normal.

Now what? Having ruled out the most common metabolic causes of vomiting, diarrhea, extreme thirst, and chronic weight loss, I needed to focus on other possibilities. I could prioritize my differential diagnoses somewhat based on age and lifestyle. As a strictly solitary indoor cat, infectious disease and intestinal parasites were less likely. And since old cats are less prone than playful, curious youngsters to swallow dangerous items like string or rubber bands, foreign body ingestion was also low on the list. “There are three major illnesses I think we should consider,” I said. “Inflammatory bowel disease, pancreatic disease, and lymphoma, in other words, intestinal cancer.” The problem is that all of these diseases require more aggressive diagnostics. A radiograph would be our first step, but this would not likely give us a definitive answer. Diseases like inflammatory bowel disease and intestinal cancer would require biopsies if we wanted a precise conclusion. For pancreatic disease, I suggested a test we call a TAMU panel (because we send it to Texas A&M University lab). The TAMU panel measures pancreatic function, and cobalamin and folate levels, to evaluate for maldigestion and/or malabsorption. In other words, the tests help determine if an animal has the necessary pancreatic enzymes for proper digestion, and if the intestines are absorbing nutrients adequately. Interpretation of the TAMU panel results are not always black-and-white but often help point us in the right direction, or at least rule out specific problems.

“Let’s start with the x-ray,” we agreed, so we could ensure we didn’t see anything obvious before deciding on our next steps. Aslan had been a cooperative patient so far. He let us take one picture, but then let us know, in no uncertain terms, that he was done for the day. I tucked him in with a snuggly blanket misted with Feliway (a calming pheromone spray for kitties), then looked at his radiograph, and went to talk with his owner. The film showed several abnormally large, gas-filled loops of intestines. Not a definitive diagnosis, but supporting the thought that his current symptoms were from primary gastrointestinal disease. He also passed some abnormal-looking stool diarrhea while here — more evidence that he was either not digesting or not absorbing nutrients properly. 

Considering his age and history, sadly, intestinal cancer was by far the most likely diagnosis, though pancreatic insufficiency or inflammatory bowel disease could not be ruled out completely. How much does it make sense to do, considering his age and prognosis? A tough decision. We treated Aslan empirically with injections of B vitamins and antivomiting medication, and sent him home on corticosteroids, while his owner decides if she wants to pursue the TAMU panel, or even referral for abdominal ultrasound and possible biopsies. Old age is not a disease … but certain diseases come with old age. They are often diseases that are not curable, though they may be treatable. As we move from medical decisions to philosophical, ethical ones, the choices get harder.