The cat’s liver has an important role in the cat’s digestion and metabolism. If the liver or bile ducts become inflamed or begin breaking down, the cat isn’t able to digest the fat in its food or process toxins, creating a potentially serious condition. Cats with cholangiohepatitis become noticeably ill, losing their appetites, vomiting, and developing jaundice.

Cholangiohepatitis in cats appears as an inflammation of the liver and biliary system. About two-thirds of cats with liver disease are diagnosed with cholangiohepatitis or hepatic lipidosis, which is also known as fatty liver.

Cats with cholangiohepatitis are visibly ill and typically demonstrate symptoms such as:

Depending on the type of cholangiohepatitis the cat has, additional symptoms may vary:

Cholangiohepatitis may be caused by a bacterial infection or a pre-existing condition. The veterinarian needs to carry out full diagnostic testing to determine whether a bacterial infection or other condition is causing the cat’s illness. 

Causes of acute cholangiohepatitis include:

Causes of chronic cholangiohepatitis include:

Veterinarians rely on a battery of tests to help them arrive at the correct diagnosis. Before deciding the cat has developed cholangiohepatitis, the vet will run blood tests, urinalysis, and a serum chemistry profile. The cat will also undergo a liver biopsy, which is the diagnostic tool that gives the most definitive diagnosis.

Urinalysis should reveal bilirubinuria, a condition in which conjugated bilirubin is detected in the cat’s urine. 

Vets should run thyroid profiles for cats older than seven years. If the cat has an overactive thyroid (hyperthyroidism), it may also have elevated liver enzymes. The vet should also order diagnostic tests to rule out feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), feline infectious peritonitis (FIP) and toxoplasmosis. Toxoplasmosis can lead to cholangiohepatitis.

Diagnostic imaging can also help to determine whether the cat has developed cholangiohepatitis. Abdominal radiography reveals several different signs that allow the vet to make a firm diagnosis.

Liver biopsy, completed via fine-needle aspiration, enables the vet to get liver cells for examination under a microscope. This test also allows the vet to determine whether the cat has the chronic or acute form of the disease.

Surgical biopsy should be ordered if:

Laparoscopy can be used to carry out hepatic biopsies, allowing the vet to see the liver and obtain larger testing samples.

The first treatment given to the cat should be stabilizing its condition and feeding via a feeding tube and intravenous fluids to help the cat to regain lost strength and help restore fluid levels to a normal level. 

Once nutrition support and intravenous fluids have been started, the vet will begin other forms of treatment, including long-term antibiotic therapy, which is most appropriate for acute cholangiohepatitis. For the chronic form of the illness, the antibiotic course of treatment is closer to four to six weeks. The antibiotics are intended to build up within the bile, allowing the cat’s biliary ducts to heal. Good antibiotic choices include metronidazole, ampicillin, cephalexin and amoxicillin. Antibiotics that are potentially poisonous to the liver should be avoided. If the cat has severe hepatic disease and is prescribed metronidazole, this should be given in lower doses. It can be given in combination with penicillin; both drugs are excreted into the bile while they are still active. If the cat has to take an antibiotic long-term, it may develop antibiotic resistance.

The cat may also begin taking a choleretic, which helps to keep the bile from becoming sludge-like. The vet may prescribe ursodeoxycholic acid as long as the cat doesn’t show signs of extrahepatic biliary obstruction. Along with this medication, a long-term immunosuppressive medication, such as prednisolone may be prescribed. 

Surgery should only be considered if discrete choleliths (gallstones) are found.

It’s important for the cat to be seen for follow-up appointments after being treated for cholangiohepatitis. Because long-term medication use is often necessary, the vet needs to see the cat to determine if the prescribed therapy is helpful or if the cat needs to be put on a different medication. 

With chronic cholangiohepatitis, the vet aims for long-term remission; this prognosis relies on the severity of the illness and any underlying causes. In cases of acute cholangiohepatitis, the prognosis is usually good, sometimes leading to a cure. 

Cats who become lethargic and stop eating should be seen by their vet to test for a return of this condition. It’s routine for the vet to take blood for test for liver values once treatment has begun.

Cats should be given medications as prescribed, for the full course of therapy. If the cat resists, other formulations may be acceptable.