Chronic hepatitis is a persistent inflammation of the liver. Cases of chronic hepatitis may be caused by an associated disorder but most cases are idiopathic, with no known cause. The liver's functions are important to metabolism in cats. The liver synthesizes proteins, bile and sugars, and also metabolizes fats. The liver removes waste products from the blood and functions to detoxify ingested poisons or drugs.
Associated Conditions of Chronic Hepatitis in Cats
Idiopathic hepatic lipidosis, or IHL, is specific to cats and is a common associated condition of chronic hepatitis. It is not known what specifically incites IHL, but obesity and stress are believed to predispose cats to the condition. The most obvious symptom is a long term loss of appetite, which causes fat accumulation in the liver. Other disorders that may be associated with chronic hepatitis include:
- Feline infectious peritonitis
- Toxoplasmosis
- Feline leukemia
- Liver fluke infection
- Poisoning (from chemicals or drug overdosage)
Symptoms of Chronic Hepatitis in Cats
Chronic hepatitis can be associated to numerous conditions or be idiopathic, but the same symptoms are almost always exhibited. Common symptoms of chronic hepatitis in cats are jaundice and ascites. Jaundice is the yellowing of the skin and whites of the eyes. This is caused by an accumulation of the liver's bile in the tissues of the body. Urine may also appear darker, similar to the color of tea. A cat with ascites may appear bloated due to an accumulation of fluid in the abdomen. Other symptoms of chronic hepatitis may include:
- Depression
- Weakness
- Lethargy
- Anorexia (loss of appetite)
- Weight loss
- Vomiting
- Diarrhea
- Polydipsia (excessive water consumption)
- Polyuria (excessive urination)
- Abdominal pain
A cat suffering from advanced stages of a liver disease may experience bleeding in the stomach, intestines and urinary tract. The mouth may also show signs of hemorrhaging that is most noticeable on the gums. Advanced liver disease may affect the central nervous system and the cat may display symptoms such as:
- Leaning the head against objects
- Appearing disoriented
- Behaving as though blind
- Stupor
- Seizures
- Coma
Clinical Diagnosis of Chronic Hepatitis in Cats
Diagnosis can be difficult because the liver is large and capable of partially regenerating itself. Symptoms may not be exhibited until the condition is severe. A veterinarian will recommend various laboratory blood tests to determine if levels of liver enzymes are abnormal or if there is associated anemia.
Radiographs, or x-rays, can show any changes in liver size but are most effective when previous radiographs are available for comparison of the healthy liver. Lesions may be present on the liver and are recognizable on an ultrasound or CT scan. A liver biopsy, or removal of a piece of liver tissue, may be necessary to confirm diagnosis and associated conditions. Serious conditions may involve necrosis of the liver. In these cases the liver changes shape and size, due to the cells of the liver dying of enzyme deprivation.
Treatment of Chronic Hepatitis in Cats
Effectiveness of treatment is dependant upon any associated disorders and the degree of liver damage. The cat may need to be hospitalized and kept on fluid therapy to replace lost nutrients. In some cases forced feeding of a prescription diet may be necessary during recovery. Serious conditions may require a gastrostomy operation so that food can be administered through an abdominal incision into the stomach.