The cause of this disorder has not been known but some of the potential causes which have been forwarded include Leptospirosis, Canine Hepatitis Virus, drug toxicity, Copper Storage Disease, and hereditary factors. The immune system may also react to the inflammatory process within the liver and contribute to the progression and worsening of the disease.
Chronic Active Hepatitis can affect any breed of dog however there has been a higher incidence in the Doberman pinscher, Bedlington terrier, Cocker spaniel, West Highland white terrier, and Skye terrier. A high incidence of CAH has also been observed in females and middle-aged animals.
A dog suffering from Chronic Active Hepatitis may show the following signs—loss of appetite and eventually weight loss, lethargy, gastrointestinal upsets manifested by vomiting and diarrhea, excessive urination (polyuria), excessive thirst (polydipsia), jaundice (yellow discoloration of the skin), ascites (presence of fluid within the abdominal cavity), and increased bleeding tendencies.
Your veterinarian may need to conduct several tests and procedures on your labrador in order to come up with a definite diagnosis of the condition. These tests may include a complete blood count (CBC), urinalysis, biochemical profile, blood clotting profile, x-rays and ultrasound of the abdomen, serum bile acids, liver biopsy, ammonia levels, and bacterial culture and sensitivity tests.
The treatment regimen involves fluid and electrolyte support to prevent dehydration brought about by severe diarrhea, polyuria, vomiting, and anorexia. There is also a need to provide nutritional support and proper dietary management.
Any underlying disorders should be properly addressed. Corticosteroids are also given to deal with the inflammation. If pathogenic microorganisms are involved, antibiotic therapy may be indicated. Choleretic medications or drugs that stimulate the normal functioning of the liver can also be administered to promote bile flow. SAMe is also given to stimulate liver metabolism.
If the cause is copper storage disease, copper-chelating drugs are given to bind and eliminate copper from the liver.
Diuretics can help eliminate water retained in the body tissues while Vitamin K prevents hemorrhage and blood loss. Anti-fibrotic medications are also given to lessen scarring of the liver.
Since there are no effective preventive measures for CAH, it is recommended that dog breeds which are highly susceptible to the disease should undergo regular biochemical profile in order to start therapy immediately while the disease is still at its early stages thus slowing down its progression and prevent the development of serious complications.