Hepatitis in Cats: Signs, Causes, and Care (Vet Answer)
You may not have heard of hepatitis in cats (more accurately referred to as cholangitis/cholangiohepatitis), but it is one of the leading causes of liver disease in our feline friends 1.
This article will explain the different types of inflammatory liver disease that occur in cats, as well as their causes, signs, treatment, and prognosis.
What is Hepatitis?
The word hepatitis means inflammation of the liver. Cats like to make things complicated, however, and do not usually develop simple hepatitis. It is common for the bile duct system, which transports bile (produced by the liver) to the gall bladder for storage, to also be affected.
Here are some other terms you may hear from your veterinarian when they are describing inflammatory liver disease in cats:
- Cholangitis: inflammation of the bile duct system (the cells of the liver itself are not affected)
- Cholangiohepatitis: inflammation of the bile duct system AND the cells of the liver
- Triaditis: the combination of cholangiohepatitis, pancreatitis, and inflammatory bowel disease (IBD) in the same patient, at the same time
A Note About Feline Anatomy
Cats are unique because the tube delivering bile from their gall bladder (the common bile duct) and the tube transporting digestive enzymes from their pancreas (the pancreatic duct) join together before opening into the small intestine. In other species, these tubes enter the small intestine separately.
This is important because, if bacteria from the small intestine enter the tube, they gain access to both the liver and the pancreas (causing infection in both). Cats with inflammatory bowel disease (IBD) appear to be at higher risk of this happening, possibly due to an overgrowth of normal bacteria and/or the presence of harmful bacteria.
An often-reported study 2 found that cats with cholangiohepatitis commonly had other inflammatory conditions at the same time:
- 83% had inflammatory bowel disease (IBD)
- 50% had pancreatitis
- 39% had both IBD and pancreatitis
What Causes Hepatitis in Cats?
The World Small Animal Veterinary Association (WSAVA) currently recognizes three different types of cholangitis/cholangiohepatitis in cats, based on their suspected causes:
- Neutrophilic: likely due to a bacterial infection
- Lymphocytic: thought to be immune-mediated (i.e., an abnormal reaction of the immune system)
- Chronic cholangitis caused by liver flukes (parasites) in tropical regions
The neutrophilic type is most commonly reported in cats and most likely to be involved in cases of triaditis.
Interestingly, researchers have discovered a feline virus (domestic cat hepadnavirus) that is similar to the human hepatitis B virus, but more studies are needed to understand its role (if any) in feline liver disease 3.
What Are the Signs of Hepatitis in Cats?
Cats are very good at hiding their illnesses in general, and liver disease is no exception.
Signs of cholangitis/cholangiohepatitis are often vague and may include:
- Decreased appetite
- Vomiting and/or diarrhea
- Weight loss
- Lethargy (extremely low energy)
- Drinking more water and peeing more than usual
- Sore and possibly swollen belly
- Jaundice (yellowish color of the eyes, gums, and skin)
If your kitty is showing any of these signs, please seek veterinary attention right away.
How is Hepatitis Diagnosed?
After a complete physical examination, common diagnostic tests for include:
- Bloodwork: complete blood count (CBC) to look at the blood cells, biochemistry panel to look at the liver enzymes and bilirubin level, a thyroid test to screen for hyperthyroidism, and specific tests to look for pancreatitis
- Radiographs (x-rays) of the abdomen to screen for liver enlargement and/or other obvious abnormalities
- Ultrasound, which is useful for assessing all of the organs in the abdomen
An ultrasound-guided needle can be used to collect a sample of bile for analysis. Some family veterinarians may offer this type of testing but, in many cases, you will be referred to an internal medicine specialist. The bile sample is then submitted to a laboratory to check for bacteria. If bacteria are present, they can be identified and challenged with different antibiotics to see which are likely to be the most effective.
An exact diagnosis often requires more invasive testing, in the form of abdominal surgery to collect a biopsy (piece) of the liver for examination under a microscope.
Your veterinarian will recommend the test(s) they think will be most useful for your particular cat, taking their whole clinical picture into account. If your kitty also has severe pancreatitis, for example, that might need to be the focus of their initial treatment and knowing exactly what is happening in the liver could be less important.
How Do I Care for a Cat With Hepatitis?
If you suspect your cat may have liver disease, the best thing you can do is seek veterinary attention right away. Waiting even a few days could allow additional problems to develop, like hepatic lipidosis (fatty liver) from not eating.
When making a treatment plan, your veterinarian will consider your cat’s whole clinical picture. Are they dehydrated? Do they need nutritional support (e.g., a feeding tube)? Do they have inflammatory bowel disease (IBD) or pancreatitis that also needs to be managed?
Many cats will have to stay in the hospital, at least initially.
Some of the medications used in the treatment of inflammatory liver disease include:
- Immune-suppressing drugs (e.g., prednisolone)
- Anti-nausea medication
- Appetite stimulants
- Medication to improve bile flow (e.g., ursodiol)
- Liver support supplements (e.g., vitamin E, silymarin, S-adenosylmethionine)
Once your cat is able to be discharged from the hospital you may need to feed them a special diet, continue giving prescription medications and/or supplements, and attend recheck appointments as recommended by your veterinarian.
Please do not change any part of your cat’s treatment plan without talking to your vet!
You will need to monitor your kitty’s appetite closely, and it can be very helpful to track their weight at home with a baby scale. Gaining weight is often a good indication that they are feeling better!
Frequently Asked Questions
Can a Cat Recover From Hepatitis?
Unfortunately, recovery from cholangitis/cholangiohepatitis is difficult to predict in cats because it depends on a variety of factors. The following can be considered very general guidelines, but please remember that every cat is unique:
- Acute (sudden) hepatitis usually has a better prognosis than chronic (longstanding) hepatitis
- Hepatitis caused by a bacterial infection generally has a better prognosis than the immune-mediated type (for which the treatment goal is remission, rather than cure)
- Cases that are identified and treated early often have a better prognosis than cases that are not found until more advanced stages of disease
It is also important to keep the following in mind:
- An exact diagnosis is often not possible without advanced diagnostic testing (e.g., bile culture, liver biopsy), which makes an accurate prognosis challenging
- The overall likelihood of recovery depends on how well any concurrent conditions (e.g., inflammatory bowel disease, pancreatitis) can be managed
Your veterinarian should be able to offer more specific insight based on your kitty’s unique situation.
Is Cat Hepatitis Contagious to People?
No, feline hepatitis is not contagious to people or other pets.
Can I Protect My Cat Against Hepatitis?
If you live in a tropical or subtropical climate like Florida or Hawaii, be sure to deworm your cat regularly (as recommended by your veterinarian) to prevent liver flukes, which can cause chronic cholangitis.
Unfortunately, we do not have many other specific strategies to prevent inflammatory liver disease in cats, but there are some general things you can do to help keep your kitty as healthy as possible:
- Help them maintain an ideal body weight to reduce their risk of conditions like diabetes and pancreatitis (which can increase the likelihood of developing other inflammatory conditions, like liver disease)
- Keep them up-to-date on all vaccinations recommended by your veterinarian to protect against diseases that affect the immune system (e.g., feline leukemia), which can make your cat more susceptible to infections
- If your cat has been diagnosed with inflammatory bowel disease (IBD), enlist your veterinarian’s help to manage it the best you can (which may reduce the risk of neutrophilic cholangitis)
- For senior cats, consider regular bloodwork to screen for hyperthyroidism and early signs of liver disease
Cholangitis/cholangiohepatitis is the second leading cause of liver disease in cats. Signs of this condition can be vague so, if you have any concerns about your cat’s health, make an appointment with your veterinarian sooner than later.
Catching liver disease in its early stages may mean more options for treatment and a better outcome for your fur baby.
Featured Image Credit: Elpisterra, Shutterstock