Cholangitis/Cholangiohepatitis Syndrome in Cats

What is cholangitis/cholangiohepatitis syndrome in cats?

Cholangitis/cholangiohepatitis syndrome (CCHS) is an inflammatory liver disease. Cholangitis is inflammation of the bile ducts. Cholangiohepatitis is inflammation of the bile ducts, gallbladder, and surrounding liver tissue. CCHS is much more common in cats than dogs.

The liver produces bile, which helps the body digest food, especially fats. Bile is stored in the gallbladder and travels through the bile ducts into the intestines, where it mixes with food. Illness can occur if bile production is reduced or if an obstruction or swelling prevents bile from passing through the bile ducts into the digestive tract.

Cats with cholangiohepatitis may also have pancreatitis and inflammatory bowel disease (IBD). The combination of these three conditions is called triaditis. Most cats with cholangiohepatitis also have inflammation of the duodenum or jejunum, which are parts of the small intestine. About half also have evidence of pancreatic disease. IBD may allow bacteria from the intestines to enter and infect the common bile duct, contributing to pancreatitis and cholangiohepatitis.

What causes CCHS?

Many conditions and factors may contribute to CCHS. It often develops along with or after another condition, such as gallstones, pancreatitis, inflammatory bowel disease (IBD), or chronic interstitial nephritis (a form of kidney disease). CCHS occurs in two main forms:

• Suppurative CCHS is caused by a bacterial infection of the gallbladder.
• Non-suppurative CCHS is not caused by a bacterial infection. It may result from immune-mediated disease, in which the immune system attacks the body’s own tissues. Certain cancers can also affect the gallbladder or bile ducts and cause a partial or complete blockage.

What are the clinical signs of CCHS?

The clinical signs of CCHS depend on the form of CCHS. The signs of suppurative CCHS are more severe and sudden, and may include:

• Painful abdomen
• Fever
• Anorexia (lack of appetite)
• Severe lethargy
• Vomiting
• Jaundice (yellowish discoloration of the skin, eyes, gums, and mucous membranes)

The signs of non-suppurative CCHS are more ambiguous and chronic (ongoing), which can make the condition more challenging to diagnose. Signs may include:

• Periods of vague clinical illness, including lethargy, vomiting, anorexia, and weight loss
• Increased appetite and weight loss, if the bile ducts become small and the cat cannot digest foods properly

How is CCHS diagnosed?

Your veterinarian will take a thorough medical history and perform a physical examination. They will also rule out other diseases that may be causing the signs or contributing to CCHS. If your veterinarian suspects CCHS, they may recommend additional tests, including:

• Serum biochemistry profile: Cats with CCHS often have elevated levels of several liver enzymes and globulins (inflammatory proteins).
• Complete blood cell counts (CBC): An elevated white blood cell count is common, especially in cats with suppurative CCHS.
• Urinalysis: Cats with CCHS may have elevated bilirubin levels in their urine.
• Pancreatic testing: Tests such as pancreas-specific lipase immunoreactivity (PLI) may be used to check for concurrent pancreatitis.
• Cobalamin (B12) and folate testing: Cats with inflammatory bowel disease often have abnormal cobalamin or folate levels.
• Diagnostic imaging: Abdominal radiographs (X-rays) are often performed but may appear normal. Abdominal ultrasound is considered the best way to diagnose CCHS.
• Ultrasound-guided sampling: Fine needle aspiration (FNA) of the gallbladder may be used to collect bile and check for abnormal cells or bacteria. An ultrasound-guided biopsy may also be recommended.
• Laparotomy (exploratory surgery): Surgery may be performed to collect biopsy samples and, if necessary, remove the gallbladder when it is completely obstructed.

How is CCHS treated?

Treatment depends on your cat's clinical signs and the underlying cause. Initial treatment focuses on stabilizing your cat and providing supportive care, such as intravenous fluids, nutritional support through a feeding tube, and medications. Medications may include antibiotics, anti-nausea medications, pain medications, corticosteroids, and ursodiol, a drug that improves bile flow. Surgery may be required if a bile duct is obstructed. Your veterinarian may recommend additional therapies based on your cat's specific condition.

What is the prognosis for a cat diagnosed with CCHS?

With timely diagnosis, appropriate treatment, and supportive care, the prognosis for cats with suppurative CCHS is generally good. In many cases, the condition can be cured.

For cats with non-suppurative CCHS, the goal of treatment is long-term remission. The prognosis depends on the severity of the disease, its underlying cause, and any other conditions the cat may have.