General Information
The liver plays a major role in food, vitamin, and hormone metabolism, contributes to immune and blood clotting activities, stores ingredients for future use, and plays a major role in digestion. The word metabolism literally means change. The liver is like a chemical plant that continually uses the substances we eat (on purpose or accidentally) and changes them into forms that the body can use or into forms that can be stored or removed (excreted) by the body. The liver also neutralizes many poisons that would otherwise cause grave results.
Because of the multipurpose nature of the liver, many mixed signs (symptoms) appear when liver destruction occurs through disease or injury. The liver can regenerate itself unless overwhelmed by harmful substances or a disease process that reduces it to a mass of scar tissue (cirrhosis).
Chronic active hepatitis (CAH) refers to a long-standing (6 months or more), currently active inflammation of the liver, and represents a group of liver diseases that have many microscopic similarities. They tend to progress to the end stage of liver degeneration known as cirrhosis.
CAH may be caused by viruses, drugs, primary liver cancers, autoimmune (self-allergy) disorders, and other obscure causes. CAH may include the infectious hepatitis virus and copper-associated hepatitis in Doberman pinschers, West Highland white terriers, and Bedlington terriers. Some examples of drugs that have been reported to cause the disorder are primidone, phenytoin, and oxibendazole. If your pet requires these drugs, liver health can be monitored through periodic blood tests. Primary liver tumors would fit in this group also.
Copper-associated hepatitis in Bedlington Terriers represents an inherited form of CAH in which large masses of copper are collected and stored within the liver. The problem is that the liver cannot excrete the excess copper into the bile that would enable the body to eventually excrete it. The liver, therefore, because it cannot tolerate such high levels of copper, becomes overwhelmingly poisoned to the point that liver cells are destroyed. The mode of inheritance is autosomal recessive, which means each parent must be a carrier for it to appear in the offspring.
Important Points in Treatment
1. It is important to identify the cause because treatment for one type of CAH will be different from that for other forms of the disease. Identification is performed through laboratory tests and liver biopsy.
2. Success of treatment often depends on the stage of liver disease when first noted and treated.