Complete Care for Your Aging Cat - Amy Shojai [115]
Blood tests, imaging techniques and symptoms can point to liver disease. But a definitive diagnosis can only be made examining tissue beneath the microscope. An ultrasound-guided needle allows cells to be collected through the abdominal wall, often without invasive surgery.
Treatment
Treatment depends on the cause of the problem and how early it’s caught. Once the liver scars from the inflammation, the damage is hard to reverse. Inflammation of the liver—the various hepatitis diseases—is treated with drugs to suppress the inflammation. Of course, the liver processes many drugs, yet is compromised. So when drug therapy is needed in these cats, veterinarians try to select drugs that rely primarily on the kidneys to process.
“If I diagnose lipacidic hepatitis in an older cat, I tend to use prednisone,” says Dr. Webster. This is not a cure, but cats do improve with this therapy and they don’t have a lot of side effects from prednisone the way dogs do. A rare complication of using prednisone would be development of diabetes.
Dr. Webster also likes to use SAMe in cats. “I’ve had a couple cats using these long term. My cat has been on those medications now for four and a half years and she’s doing pretty well.” The nutraceutical SAMe (S-Adenosylmethionine) increases antioxidant levels in liver cells to protect them from toxins and death. An oral medication, brand name Actigall or Ursodiol, is a naturally occurring bile acid that also can help protect the liver from further damage.
Silymarin (milk thistle), and its active component silybin are anti-hepatotoxic flavonolignans. They also have been administered to animals with hepatotoxic drug injury. Whether or not silymarin will help an animal with chronic liver disease has not been determined. The oral absorption of silymarin from available formulations has not been established, but this may be an avenue your veterinarian wishes to pursue. A new compound Denamarin™ is available containing SAMe and silibinin-phosphatidylcholine
and is available in a chewable formulation.
Vitamin therapy may also benefit cats with liver disease, according to David C. Twedt, DVM, an internist at Colorado State University. Dietary supplementation with vitamin E reduces oxidant injury to hepatic tissue. Vitamin E is recommended at a dose of 10 IU/kg/day, and the natural form (d-Alphatocopherol) is more helpful than synthetic forms. Vitamin K stores in the liver can become depleted with advanced liver disease, so supplementation helps counter this loss. B vitamins may become deficient in cats with liver disease, and because they are water-soluble and relatively nontoxic, supplementation using a B-complex formulation is recommended. Cats with liver disease are particularly prone to vitamin B12 (cobalamin) deficiency. The recommended dose of cobalamin for cats is 250 μg given subcutaneously weekly until normal cobalamin concentrations are maintained.
In a study where carnitine was given to obese cats undergoing rapid weight loss from caloric restriction, researchers found it protected against hepatic triglyceride accumulation. Supplementation of 250 mg of carnitine a day in lipidosis cats is reported to be associated with better survival rates.
For cats that are acutely ill and refuse to eat for days and even weeks, a feeding tube may be placed to allow the cat to be fed a soft diet, either while in the hospital or after going home. It may take weeks of tube feeding before the cat’s appetite returns to normal. Cats tolerate these tubes quite well, though, and most owners become adept at feeding the cat in this way.
Once the cat’s appetite returns, the right diet helps them recover. “Cats have some very peculiar amino acid requirements, and these are particularly important in liver disease,” says Dr. Davenport. Arginine, taurine and carnitine are critical. “Carnitine is really more of an amino vitamin than an amino acid, but it’s integral to the shunting of fat