By Christie Long
Hepatitis is one of those conditions that sounds like a diagnosis, but really isn’t.
You can compare it to anemia — we might know that a patient’s red blood cell count is low, but knowing that doesn’t tell us why or how to treat it.
Hepatitis is similar, in that we know it means that the liver is inflamed, but we may not know why. There are a number of things that cause hepatitis, and knowing or at least suspecting the right cause is crucial to proper treatment.
Veterinarians will often put cases of hepatitis into one of two categories: chronic, or longstanding hepatitis, and acute, or recent-onset hepatitis. Animals with chronic hepatitis can have acute incidents where their disease gets worse for a period of time. Animals with hepatitis often look a lot like animals with other, fairly routine illnesses, so it’s easy to overlook this more serious condition. Affected animals may stop eating all together, or just eat less.
They may vomit or have diarrhea. Dogs especially will often start drinking much more water and subsequently urinating more, sometimes to the point of having accidents in the house despite being successfully housebroken for years. Many people are aware that serious liver disease can cause the whites of the eyes and even the skin itself to take on a yellowish-cast, but this often doesn’t happen until the disease is advanced.
Blood work often gets us started down the road to understanding that a pet has hepatitis; but as I mentioned above, it doesn’t tell the whole story. These animals will typically need advanced blood testing and ultrasound imaging to rule out other processes, such as cancer or birth defects that result in abnormal liver circulation. In adult dogs, hepatitis can have an infectious cause. Certain strains of leptospirosis, a bacterial infection passed through contact with urine, can cause acute hepatitis. Infections can also ascend into the liver and gallbladder from the gastrointestinal tract, via the bile duct.
There are also immune-mediated causes of hepatitis. Similarly to diseases like rheumatoid arthritis, the body perceives its own tissue as foreign and begins to attack it, as it if were an invader from the outside. Some breeds of dogs, such as Bedlington terriers and West Highland white terriers, can have an inherited form of hepatitis that results in the inability of their livers to appropriately metabolize copper. Cats often have a form of hepatitis that involves both the liver and the gall bladder.
All of these conditions have different treatments. Infections require use of appropriate antibiotics; immune-mediated disease responds to appropriate doses of immunosuppressive drugs, often given for long periods of time. Managing copper storage disease involves limiting ingestion of dietary copper and using special drugs that bind copper and help the body eliminate it.
Because there are so many causes of hepatitis, determining an appropriate treatment plan can sometimes only happen after a biopsy is taken of the liver tissue itself. With this, we can better understand what’s causing the problem, and treat it effectively.
Christie Long is a veterinarian at the VCA Animal Hospital in Fort Collins, CO. Long left her job in software sales in 2000 to travel for 13 months. Along the way, she was touched by the plight of the animals she saw and somewhere in the Nepalese Himalayas she vowed to return to school to become a veterinarian. While she often finds end-of-life situations heart-wrenching, she considers herself blessed to be called upon as a trusted adviser to families during difficult times. Dr. Long’s family includes her husband and travel partner, Wiley, their 5-year-old son, Wiley IV, their dogs Pancake and Gizmo and cats Sneaky and Sidh.