Feline Body Parts – The Cat’s Liver
Feline Body Parts – The Liver
“Liver Me This”
by Arnold Plotnick, MS, DVM, ACVIM
- Published in Catster Volume 1, No. 3, Sept/Oct 2015
“What am I? Chopped liver?” You’ve probably heard this figure of speech before, the speaker implying that he’s worthless. I can assure you, as a cat veterinarian, that the liver (unchopped, at least) is anything but worthless. In fact, the liver is one of the most important and versatile organs in the body. If you’re impressed with the ability to multitask, then you’ll really admire the liver. It stores glucose, to supply the body with energy when needed. It makes clotting factors, to control bleeding. It detoxifies the blood. It stores vitamins and minerals. It helps digest food. It metabolizes drugs. You name it, the liver probably does it.
When examining a cat at my cats-only veterinary practice, there are some things that clue me in that the liver may not be working perfectly. The biggest clue would be the presence of jaundice. This is a yellow discoloration of the tissues, which is mainly visible in the whites of the eyes, on the gums, and in the skin inside the ears. If the whites of the eyes are the color of a New York City taxicab, a liver problem rises to the top of my list.
An important part of any feline physical examination is “abdominal palpation”. This is the gentle pressing and feeling of the abdominal organs. Normally, the liver can barely be felt protruding beyond the last rib. If I detect an enlarged, firm, or irregular feeling liver, I start to worry about liver disease.
The most consistent clinical symptom of liver disease is poor appetite. Vomiting is another common finding. Because these signs are pretty non-specific, blood tests are usually necessary to confirm our suspicions that liver function has gone awry. If I see elevated liver enzymes on a chemistry panel, it supports my notion that the liver is affected.
Once we’re pretty certain that the liver is the culprit for kitty feeling sick, our next step is to figure out exactly which liver disorder is present. Achieving a definite diagnosis usually requires obtaining a biopsy specimen. Ultrasound can give us lots of information about the liver, and we can usually biopsy the liver during the ultrasound procedure. (We make sure kitty is asleep for this, of course.)
The most common liver disorder in cats is hepatic lipidosis, or “fatty liver disease”. The classic scenario for this disorder to arise is when a chubby cat decides to stop eating. The body reacts to this by breaking down fat, to supply the kitty with energy, but something goes wacky with the cat’s metabolism, and the fat clogs up the liver instead. The treatment for fatty liver disease is food, food, and more food. Because these cats have no appetite, some may require syringe feeding or even a special feeding tube to supply enough nutrients to overcome the disorder.
Hepatitis (inflammation of the liver) is another common liver malady. If the biopsy specimen shows lots of infection-fighting cells in the liver, a bacterial hepatitis is the likely cause, and antibiotics would be warranted as a treatment. If the biopsy shows many inflammatory cells in the liver, an inflammatory hepatitis is the likely diagnosis, and anti-inflammatory drugs would be prescribed. Sadly, liver cancer does occur in cats now and then. Sometimes it’s a primary cancer (the liver itself becomes cancerous). In other cases, a cancer in another part of the body may spread to the liver. Treatment would depend on the type of cancer. If a discreet portion of the liver is affected, surgery to remove that part might be curative. If the liver is diffusely affected, chemotherapy could be an option.
Because the liver enzymes are often elevated when you run a chemistry panel on a cat with liver disease, we often monitor how the cat is responding to treatment by checking the chemistry panel during therapy and seeing if the numbers are returning to the normal range. I’ve treated many cats with liver disease, and as the medicine that I prescribe starts to work its magic and the cat starts eating and gaining weight, I’ll anxiously run a chemistry panel to confirm the progress I’m seeing. Telling a client that their cat’s liver parameters have returned to normal is news that I love to de-liver. (Couldn’t resist. Sorry.)