Hepatic Lipidosis in Cats
Dr. Arnold Plotnick
Veterinary care should include diagnostic tests and subsequent treatment recommendations. Medical history review and complete physical exam. A history of obesity and sudden onset of anorexia after a stressful event is a classic finding in hepatic lipidosis. Physical exam usually reveals dehydration, severe weight loss, drooling and jaundice.
There are a variety of diagnostic tests that may be run so that a diagnosis of hepatic lipidosis can be made. These tests may include:
A complete blood count usually reveals mild anemia, and abnormally shaped red blood cells (known as poikilocytes), which are often an indicator of liver disease.
Blood tests that test organ function are especially important. Cats will usually have moderate to severe elevations of several liver parameters. A thyroid test is necessary to rule out a hyperactive thyroid as a cause of the liver enzyme elevations.
A bile acid test is a special blood test that may be necessary. It requires a blood sample after a 12 hour fast. The cat is then fed (force fed, if necessary), and another blood sample is taken two hours later. This simple test assesses the function of the liver.
Analysis of the urine may give information concerning the function of the liver.
X-rays of the abdomen allows assessment of the size and shape of the liver, and may help rule out a tumor as a cause of the liver problems.
Ultrasound of the abdomen allows limited assessment of the internal structure of the liver. It allows some assessment of the gall bladder and biliary system, and may rule out cancer as a cause of the liver disease. It may also help provide a method for obtaining a biopsy sample.
A fine-needle aspirate of the liver is a small sample of liver cells that are obtained by inserting a needle into the liver. This technique requires no or minimal sedation, and complications are extremely rare. Results must be interpreted cautiously, however, because concurrent liver diseases cannot be ruled out and may be missed.
A liver biopsy, in which a small sample of liver tissue is obtained, is the definitive test for diagnosing hepatic lipidosis. A biopsy specimen may be obtained surgically, or may be obtained using a special instrument that is inserted into the abdomen while being guided by the ultrasound probe. Surgical biopsies can be obtained by most veterinarians. Ultrasound-guided biopsies are often referral procedures.
Therapy for hepatic lipidosis is aimed at reversing the accumulation of fat in the liver, and treating the signs of liver dysfunction. The primary treatment for reversing the fat accumulation is aggressive nutritional support.
Dietary therapy is the mainstay of treatment. High protein diets are usually recommended (except in cases where the cat is showing mental signs of liver disease). Because nearly all affected cats are completely anorectic, food is administered through a nasal, esophageal, or stomach tube. This requires hospitalization, and sedation or anesthesia.
Several dietary supplements such as carnitine or arginine may be beneficial in treating cats with hepatic lipidosis, and may be recommended or prescribed by your veterinarian.
Vomiting is a frequent finding in cats with hepatic lipidosis. Many cats require a medication to help control vomiting, such as metoclopramide, especially during the initial 1 or 2 weeks of tube feeding.
Some cats with liver disease develop ulcers and subsequent gastrointestinal bleeding. Drugs that control gastric acidity, such as Tagamet, Zantac or Pepcid, may be necessary to help control this. Carafate, a gastric protectant, may be used in conjunction with the antacids.
Antibiotics may be necessary in severe cases. They help kill off bacteria that produce harmful toxins that may lead to various mental manifestations of liver disease (drooling, depression, blindness, seizures).
Blood transfusions may be needed if the liver is so impaired that it cannot produce adequate clotting factors or cannot regulate the ability of the blood to clot properly.
Appetite stimulants (oxazepam, cyproheptadine) may be tried, but are seldom useful. They seem to work best in the recovery phase of the disease.
Ursodeoxycholic acid, a drug that improves bile flow within the liver, may be helpful in selected cases.