Liver disease in pets as well as people is very complex. The scope of the pathology and disease is far beyond this short article.
The liver is the main filtering and clearing house of the body. All blood supply travels through the liver to be detoxified. There are many causes of liver disease-genetics ( see portal shunts in the library) copper storage diseases, drug induced diseases, poisons, pancreatitis, cushings disease, malnutrition, parasites, environmental stresses, cancer, trauma, and infectious diseases (bacterial, viral, fungal), just to name a few. (see below)
When diagnosed early, treatment of liver disease can be very rewarding. Diagnosis includes blood tests (lab interpretations) such as an ALT (SGPT), alkaline phosphophotase, bilirubin, total protein, bile acids etc. X-rays and ultrasounds are also very important in the diagnose of this disease Liver biopsies may also be an invaluable aid in the determination of the type of liver disease.
Listed below are several of the more common diseases of cats and dogs:
Hepatic Encephalopathy:
A metabolic disorder affecting the CNS that develops as a result of hepatic disease causing seizures.. The end result is the accumulation of ammonia in the blood stream due to prolonged circulation of toxins in the blood stream from portal shunts, cirrhosis, or end stage liver disease.
Clinical signs include: excessive drooling in cats, behavior changes, visual defects (blindness), circling, pacing, anxiety, stupor and seizures. These signs are more prevent after eating due to the increased amount of ammonia in the blood stream affecting the brain.
Causes: portal shunts, infectious hepatitis, cirrhosis, dietary restriction of argenine in cats and ferrets.
Treatment: repair portal shunt if possible, low protein diet, antibiotics such as neomycin affecting intestinal flora to reduce the production of ammonia, lactulose to aid in the absorption of ammonia, and low protein diets.
Acute Hepatic Failure
A rapid loss of liver function due to death of liver cells.
Causes: drugs, toxins, infectious diseases, and lack of oxygen.
Clinical signs: acute depression and illness-vomiting, icterus, diarrhea, seizures, hemorrhage
Diagnosis: abnormal laboratory values, abnormal x-rays and ultrasounds, and biopsy
Treatment: IV fluids, intestinal sedatives, plasma if indicated, antibiotics, vitamins
Hepatic Lipidosis (Fatty Liver)
The accumulation of fat within the liver.
Causes: loss of appetite which promotes the accumulation of lipid in the liver. This leads to a decreased in liver function. Underlying causes include-primary liver disease, shunts, diabetes, intestinal disease, pancreatitis, cancer, and other illnesses causing loss of appetite.
Signs: loss of appetite, weight loss, icterus, vomiting, enlarged liver on palpation.
Treatment: Dietary therapy is the primary treatment . High protein high calorie diets should be fed either by force feeding or by stomach tube. This process of tube feeding may last for 6-8 weeks. In our practice we place a either a PEG tube or pharyngeal tube surgically. Iv fluid therapy and antibiotics as well as vitamin therapy is also done.
Hepatitis Chronic Active
Inflammation of the liver resulting in the accumulation of inflammatory cells and scarring. This disease is more common in dogs and is due to many causes.
Causes: infectious canine hepatitis, leptospirosis, immune mediated diseases, copper storage diseases of Bedlingtons and Westies (see below).
Diagnosis: Laboratory tests, x-rays, ultrasounds, biopsies
Treatment: A diet of high calorie and low in protein (HILL’S LD Diet), IV fluids, steroids, broad spectrum antibiotics, ursodiol (Actigal), B-complex and vitamin K.
Copper Storage Disease: Bedlington Terriers and West Highland White Terriers :a genetic disease caused by accumulation of copper in the liver. This may also be seen in Doberman Pinchers and Skye Terriers. Copper is found in all foods then absorbed by the intestines, stored in the liver and excreted through the bile system. These breed genetically have the inability to eliminate copper from the liver. As many as 2/3 of Bedlingtons in the USA have this disease and may be clinically affected. Westies do not show the clinical signs of the disease even though they may have high levels of copper. Other breeds affected are cocker spaniels, keeshonds and Labrador retrievers.
Diagnosis: Blood tests, x-ray, ultrasound and biopsy,
Treatment: Iv fluids, lactulose, d-penicillamine for binding the copper, and zinc acetate given before feeding. Vitamin C may also help reduce the absorption of copper??
Elimination of carriers if vital . A registry is available at the Canine Liver Registry, Veterinary Medical Data Base, 1235 SCC-A, Purdue University, West Lafayette, In. 47907
Infectious hepatitis:
A viral disease targeting the liver, kidneys, eyes, and blood stream.
Clinical signs: fever, loss of appetite, vomiting, diarrhea, abdominal pain,
Diagnosis: Blood tests, x-rays, ultrasound, liver biopsy.
Treatment: This disease is preventable with vaccination. Treatment is supportive-IV fluids, antibiotics, highly digestible diets.
Leptosiprisos Hepatitis:
A bacterial disease caused by leptospirosis. This is a potential communicable disease to people.
Clinical signs: Depression, loss of appetite, signs of kidney disease, respiratory disease.
Diagnosis: Blood tests, serum testing for leptospirosis, urine culturing
Treatment: IV therapy, Procaine penicillin G, or enrofloxicin
Other liver diseases include:abscess of the liver, benign tumors, cancer, toxins, parasites,
There are many types and clinical signs of liver cancer. Treatment is often not rewarding as the disease is diagnosed when the cancer is to far advanced. Diagnosis may be made by blood tests, x-ray, ultrasound, laproscopy, CAT scan, and exploratory surgery.
End stage liver (illustration) disease encompasses may types of pathology. Cirrhosis is one form of end stage liver disease. As the disease progresses, the liver is unable to filter and process properly. As a result, the body is overwhelmed with toxins such as ammonia. When this occurs , your pet may develop a seizure like disorder as a result of the toxins. Diets low in protein as well as medications to bind the ammonia may be of use to help minimize the clinical signs as well as prolong your pet’s quality of life.