Diseases associated with the liver, gallbladder, and/or bile duct system can be confusing for pet owners because these diseases can have really vague symptoms. It’s not always clear why they happen, and the terminology used to describe them tends to sound like a foreign language. Cholangitis/cholangiohepatitis, the second most common type of liver disease seen in cats, is a prime example. This disease is sometimes referred to as cholangitis, sometimes cholangiohepatitis, and sometimes cholangitis/cholangiohepatitis syndrome. In addition to these names, several different forms of the disease exist, which all have their own names. To add to the confusion, sometimes other diseases can occur at the same time as cholangitis/cholangiohepatitis, which makes figuring out the cause for the symptoms and diagnosing the problem pretty difficult.
Cholangitis means inflammation of the biliary tree (also called the biliary tract or bile duct system), which connects the gallbladder and liver and helps these organs make, process, store, and secrete bile. Bile is used to break down fat from food in the intestines. Cholangiohepatitis means inflammation of the biliary tree as well as the surrounding liver cells. Cholangitis/cholangiohepatitis can be caused by bacterial infection, in which case the disease may be called neutrophilic cholangitis. It can also be caused by a parasite known as a liver fluke, which causes inflammation after it invades the liver. Another type is called lymphocytic cholangitis. It is associated with lymphocytes, a type of white blood cell involved with the immune system, and it likely occurs because of an overreaction by the immune system.
Pancreatitis, or inflammation of the pancreas, and inflammatory bowel disease, an immune-mediated condition associated with inflammation, poor digestion, and poor absorption of nutrients within the gastrointestinal tract are common conditions that occur in cats that develop cholangitis/cholangiohepatitis. Veterinary scientists don’t know exactly why these diseases happen together, but over 50% of cats have one or both of these diseases in addition to cholangitis/cholangiohepatitis.
Clinical Signs and Symptoms
Depending on what type of cholangitis/cholangiohepatitis a cat has, the symptoms may occur slowly, over a long period of time (chronic) or happen suddenly (acute). Common signs include poor appetite, throwing up, diarrhea, acting tired, drinking and urinating a lot, fever, weight loss, belly pain, swollen belly, and a yellow tinge (jaundice) to the skin, gums, and eyes may be seen.
Lab tests will be run on the cat’s blood to see how the red blood cells, white blood cells, and platelets are handling the disease. This type of test is called a complete blood count or CBC. A chemistry lab test will also be run, which will show the disease’s effects on the liver as well as other organs. Findings that point towards cholangitis/cholangiohepatitis include high liver enzymes. Increased levels of bilirubin, which is a product of the breakdown of red blood cells by the liver, can also be seen. At high levels, bilirubin can cause jaundice (yellow-tinged skin, eyes, and gums). Other tests include abdominal x-rays and ultrasound to examine the liver, gallbladder, and biliary tree. Ultrasound can also be used to sample the bile to check for and culture bacteria. Finally, to officially diagnose cholangitis/cholangiohepatitis, biopsies of the liver tissue are needed. These can occasionally be done with abdominal ultrasound, but often surgery is needed to get large enough pieces of diseased tissues for a pathologist to properly examine.
Treatment may depend on the cause or reason for the cholangitis/cholangiohepatitis (e.g. immune-mediated vs. bacterial infection). If the cat has pancreatitis or inflammatory bowel disease, those will require treatment as well. Antibiotics are commonly used although they may be switched to different kinds depending on the bile culture results. Antibiotics are usually needed for at least 1-2 months and should be continued even once the pet starts feeling better. Steroids to suppress the immune system may be needed. Supplements or medications to help support the liver and biliary tree may also be prescribed, including ursodiol, vitamin E, and SAMe. Do not start any supplements without consulting your vet.
In addition to medications, very sick cats may need hospitalization, IV fluids, a feeding tube, and/or surgery to remove the gallbladder. Surgery is usually only needed if an obstruction or blockage occurs within the biliary tree/bile ducts. Prognosis, or chance for improvement, varies depending on the cause. Cats with acute neutrophilic cholangitis, which is a sudden onset bacterial infection of the biliary tree, usually recover. Those with chronic or long-term forms, or lymphocytic forms of cholangitis, tend to respond poorly to medications and the disease can worsen over time to the point of liver failure.
If you suspect your cat has a form of cholangitis/cholangiohepatitis, or you have questions about the disease, call your veterinarian for further information.