Cholangiohepatitis in Cats
Overview of Feline Cholangiohepatitis
Cholangiohepatitis is an inflammation of the biliary structures (the system that carries bile) and the surrounding liver tissue. In the cat it occurs in several forms, including suppurative cholangiohepatitis, nonsuppurative cholangiohepatitis, and biliary cirrhosis. In the suppurative form of the disease, white blood cells called neutrophils are commonly seen in biopsies. In the nonsuppurative form of the disease, white blood cells called lymphocytes and plasma cells are most commonly seen on biopsy. With cirrhosis, extensive scarring is found in both the biliary system and the liver.
This is a syndrome seen primarily in cats and infrequently in dogs. All breeds of cats can be affected, although the incidence is greater in the Himalayan, Persian, and Siamese cat. Cholangiohepatitis usually occurs in middle-aged animals, and males appear to be at higher risk for the suppurative form.
Causes of Suppurative Cholangiohepatitis
- Ascending bacterial infection from the intestinal tract, which may be associated with other diseases such as bacterial and parasite infections and pancreatitis.
- Infections carried through the blood stream (blood-borne), such as bacterial (e.g. Salmonella), parasitic (e.g. toxoplasmosis), and viral (e.g. feline infectious peritonitis virus) infections
Causes of Nonsuppurative Cholangiohepatitis
This type of cholangiohepatitis is thought to be an immune disorder associated with the following conditions:
- Cholecystitis (inflammation of the gallbladder)
- Cholelithiasis (stones in the gallbladder)
- Pancreatitis (inflammation of the pancreas)
- Extrahepatic biliary obstruction (blockage of the bile duct outside the liver)
- Inflammatory bowel disease
- Chronic interstitial nephritis (an inflammatory disorder of the kidney)
- Idiopathic (unknown causes)
What to Watch For
- Loss of appetite
- Vomiting, diarrhea
- Jaundice (yellow color to the skin)
- Lethargy, collapse
- Ascites (fluid in the abdomen)
- Weight loss
- Disorientation, blindness, seizures, excessive salivation associated with severe liver disease
Diagnosis of Cholangiohepatitis in Cats
Diagnosis of cholangiohepatitis can be difficult and often requires the use of multiple diagnostic tests. Your veterinarian may refer your cat to a specialist in veterinary internal medicine for further evaluation. Tests that may be needed to reach the diagnosis and to determine the severity of the disease, include the following:
- A complete blood count (CBC), biochemical profile and urinalysis
- A coagulogram (clotting profile) to test the ability of the blood to clot
- Serum bile acids to determine how severe the liver is changed
- Ammonia levels, especially if the cat is disoriented or blind
- Abdominal radiographs (X-rays)
- Abdominal ultrasound
- Blood tests for toxoplasmosis, feline infectious peritonitis and other viral infections
- Exploratory laparotomy (abdominal surgery) to examine the liver, gall bladder and associated structures
- Laparoscopy to allow visualization and sampling of abdominal structures through a scope introduced through a tiny incision in the abdominal wall
- Liver biopsy with bacterial culture and sensitivity testing to confirm the diagnosis
Treatment of Cholangiohepatitis in Cats
- Hospitalization and supportive care (fluid and electrolyte therapy) as needed for dehydration from severe vomiting, diarrhea, and anorexia
- Treatment of any underlying medical disorders
- Antibiotic therapy
- Immune modulating drugs (drugs that alter the immune system) for the nonsuppurative form of the disease
- Nutrition and dietary management
- Vitamin supplementation
- Diuretics to help the body eliminate excess abdominal fluid)
- Choleretic drugs to enhance the flow of bile
- Lactulose to slow the absorption of ammonia from the colon so that the diseased liver does not have to process so much ammonia
- Surgery may be indicated to address underlying causes such as cholecystitis (removal of gall bladder), cholelithiasis (removal of gall stones), and extrahepatic biliary obstruction (surgical correction of the obstruction).
Home Care and Prevention
Therapy is often required long-term and numerous evaluations may be required to determine the response to therapy. Administer all medication and recommended nutritional supplements as directed by your veterinarian. Return for follow up examinations and biochemical evaluations.
There are no preventative measures recommended in these patients; however, controlling inflammatory bowel disease may be of benefit in some cases.
In-depth Information on Cholangiohepatitis in Cats
Cholangiohepatitis is an inflammatory disorder of the bile ducts and adjacent liver tissue. It is one of the more common liver diseases seen in cats and is recognized only infrequently in dogs. Most cats have few clinical signs early in the disease process, although they may develop a variety of severe and often life-threatening clinical signs as the process progresses.
The disorder is generally subdivided into several types, based on the biopsy findings within the liver.
- Suppurative cholangiohepatitis may arise with infections, usually bacterial in nature. This type has an acute (rapid) onset and is often associated with severe and devastating symptoms.
- Nonsuppurative cholangiohepatitis, which is usually associated with a more chronic (long-term), insidious course where clinical signs may be mild and vague for weeks or months before the cat is brought in for evaluation. The nonsuppurative form is thought to involve an immune-mediated mechanism secondary to other disorders.
- Biliary cirrhosis. This form is characterized by severe scarring in the biliary system and liver and may be the final end-stage of the other two forms of the disease.
Differential Diagnosis for Cholangiohepatitis in Cats
There are several diseases/disorders that appear similar to cholangiohepatitis. These include:
- Feline hepatic lipidosis. This is a syndrome seen in cats where there is a build up of fat in the liver, causing a decreased flow of bile and dysfunction of the liver.
- Portosystemic shunts. These are abnormal blood vessels present at birth that shunt blood away from the liver. Clinical signs associated with these shunts usually arise within the first year or two of life, whereas signs from cholangiohepatitis usually arise in older cats.
- Hepatic neoplasia (cancer of the liver). Lymphosarcoma can cause changes in the liver and clinical signs very similar to cholangiohepatitis, and it should be considered in all cats with liver disease.
- Exposure to hepatotoxins. Hepatotoxins are agents or drugs harmful to the liver. These include heavy metals (e.g. lead, arsenic, mercury, copper), anti-inflammatory agents (e.g. steroids, carprofen), anticonvulsants (e.g. diazepam, phenobarbital, phenytoin), griseofulvin, and certain chemical dips and sprays (especially flea and tick products).
- Extrahepatic biliary obstruction (blockage) secondary to tumors, inflammation, infection, or parasite infestation
- Pancreatitis, an inflammation of the pancreas
- Pancreatic neoplasia blocking the biliary tract
- Intestinal inflammation, tumors or foreign bodies
Other disorders associated with ascites (fluid in the abdominal cavity) also need to be differentiated or ruled out:
- Protein-losing enteropathy, which are intestinal disorders that cause profound protein loss such as inflammatory bowel disease, lymphangiectasia, and neoplasia. These conditions may result in ascites.
- Protein-losing nephropathies are kidney disorders that result in protein loss. The most common are glomerulonephritis (inflammation of a part of the kidney) or amyloidosis (the deposition or collection of a type of protein in organs and tissues that compromise their normal function).
- Right heart failure can cause a fluid build-up in the chest and/or abdominal cavity.
- Carcinomatosis is widespread cancer throughout the abdominal cavity.
Other disorders associated with jaundice need to be considered:
- Infectious diseases such as hemobartonellosis, babesiosis, leishmaniasis, feline infectious peritonitis, toxoplasmosis and liver flukes
- Autoimmune hemolytic anemia, which is destruction of red blood cells by the immune system
- Drug induced hemolysis, or breakdown of red blood cells, from ingestion of methylene blue and acetaminophen
- Other inflammatory liver diseases
- Primary gallbladder diseases (stones, cancer, inflammation, infection) that clinically mimic cholangiohepatitis
- Coagulopathies (bleeding disorders) including thrombocytopenia (decreased platelets), warfarin ingestion (usually from rat poisons), and disseminated vascular coagulation (DIC)
Certain diagnostic tests must be performed to make a definitive diagnosis of cholangiohepatitis and, as importantly, exclude other disease processes that may cause similar symptoms. Obtaining a complete history, description of clinical signs, and thorough physical examination are all important in obtaining a diagnosis. Ultimately, a liver biopsy is necessary to obtain a definitive diagnosis.
The following tests are recommended to rule out other disorders and to confirm a diagnosis of cholangiohepatitis.
- A complete blood count (CBC) may be within normal limits, or may reveal a mild anemia and/or an elevation in white blood cell count.
- A biochemical profile usually reveals elevations in liver enzymes, and may reveal electrolyte abnormalities, an elevated bilirubin, low albumin (a protein), elevated globulin (a protein), low blood sugar, low blood urea nitrogen and low cholesterol. It also may help rule out other disease processes.
- A urinalysis helps assess the kidneys and level of hydration of the patient and may reveal bilirubin in some cases.
- A coagulogram (clotting profile) should be assessed, as clotting disorders are not uncommon with liver disease.
- Serum bile acids are paired blood tests obtained before and after a meal that evaluates liver function. This is the test of choice to assess liver function. The test is very safe and can be performed at your local veterinary hospital.
- Ammonia levels are blood tests that when abnormal, often correlate with liver disease. Test inaccuracy is a concern, as many factors affect test results, and special handling is necessary.
- Abdominal radiographs (X-rays) may be within normal limits, although may reveal enlarged liver (hepatomegaly), gallstones (cholelithiasis), and occasionally, fluid in the abdomen (ascites).
- Abdominal ultrasound is recommended in most cases to evaluate all of the abdominal organs, including the liver. It is equally important to rule out other disorders or diseases that may initially be difficult to differentiate from or associated with cholangiohepatitis. With the guidance of ultrasound, it is often possible to obtain a sample of the liver via aspirate or biopsy for evaluation and culture/sensitivity. A clotting profile should be performed first, and tissue should only obtained if the clotting parameters are within normal limits.
Ultrasound is often considered the diagnostic tool of choice. The ultrasound itself is a noninvasive procedure, although sampling of the tissue will often necessitate sedation or general anesthesia, and is associated with some minor risks. These procedures generally necessitate the expertise of a specialist and/or referral hospital.
Your veterinarian may recommend additional tests to exclude or diagnose concurrent conditions, or more definitively diagnose cholangiohepatitis. These tests are not necessary in every case, however may be of benefit in certain individuals, and are selected on a case-by-case basis. These include;
- Laparoscopy. This procedure allows visualization and sampling of abdominal structures by an instrument introduced through a tiny incision. It is more invasive than ultrasound-guided biopsies, although it allows direct visualization of the liver and associated structures and generally facilitates a larger biopsy. It necessitates general anesthesia, however, and should be performed by an individual and facility that are experienced and have the appropriate instruments.
- Laparotomy. Abdominal exploratory surgery allows close inspection of the entire liver and other abdominal structures. It allows large biopsy samples to be obtained, and may be indicated in cases where an extrahepatic biliary obstruction needs to be relieved and diverted. This procedure should be left to an individual who has experience and expertise, and performed in a facility where close postoperative monitoring is available.
Patients with cholangiohepatitis may need to be hospitalized and treated aggressively. Depending on the stage of disease and clinical signs involved, outpatient therapy may or may not be sufficient. It is extremely important to have a diagnosis confirming the exact type of cholangiohepatitis involved, as treatment protocols will vary.
- Hospitalization and support (fluid and electrolyte therapy) should be instituted as needed for dehydration and electrolyte disturbances from severe vomiting and diarrhea.
- Providing nutritional support through parenteral (intravenous) routes may be needed in some cases.
- Attend to any underlying cause such as inflammatory bowel disease or pancreatitis. Surgery may be indicated to address underlying causes such as cholecystitis, cholelithiasis, and extrahepatic biliary obstruction.
- Antibiotic therapy is indicated in cases of suppurative cholangiohepatitis. Initially, while pending the culture and sensitivity report on the liver and/or bile, a broad spectrum antibiotic, such as Ampicillin, should be instituted. A three to six month course of antibiotics should be continued as dictated by the sensitivity pattern. Metronidazole (Flagyl®) has been recommended for both forms of the disease, as not only is it an excellent antibiotic for anaerobic infections (a type of infection), it also has anti-inflammatory and immune modulation properties as well.
- Immunomodulatory drugs (drugs that alter the immune system), specifically corticosteroids (prednisolone), are used in the treatment of the nonsuppurative form for their anti-inflammatory and immunosuppressive qualities. Continuous or intermittent therapy may be recommended on a long-term basis. Other agents have been used in conjunction with corticosteroids with variable results.
- Diuretics (drugs that facilitate removal of fluid) such as spironolactone (Aldactone®) may be indicated in cases with ascites.
- Choleretic drugs (drugs that enhance bile flow) such ursodeoxycholic acid (Actigal®) are recommended as they thin bile and enhance flow through the biliary tract. Additionally, they act as anti-inflammatory agents in conjunction with other drugs.
- Treatment for hepatic encephalopathy (a disorder affecting the central nervous system secondary to advanced liver disease) is indicated when present. Lactulose, a substance that slows absorption of ammonia from the intestinal tract, should be administered orally. It can also be used rectally as an enema, when diluted with warm water. Antibiotics, such as neomycin or metronidazole are also recommended in conjunction with lactulose.
- Dietary recommendations for animals with liver disease include protein modification. A major dilemma in formulating diets for animals with liver disease is the fact that these animals are often malnourished, and it is vitally important to maintain body weight and muscle mass while minimizing the signs of liver failure. There are prescription diets that are designed to provide reduced levels of high quality protein, such as Hill’s Prescription Diet L/D®, as well as ways to formulate homemade diets to provide similar benefits.
- Vitamin supplementation including injectable vitamin K and water soluble vitamins are indicated.
Follow-up Care for Cats with Cholangiohepatitis
Optimal treatment for your pet requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your cat does not improve rapidly.
Administer all prescribed medications and dietary changes as directed. Alert your veterinarian if you are experiencing problems treating your pet.
Initially, blood tests are taken every few weeks to monitor the cat’s progress. Eventually the tests are then taken every four to six months. In some cases, a second liver biopsy is recommended to assess response to therapy after some time has passed.
The prognosis for cats with cholangiohepatitis is quite variable and unpredictable. Individuals with suppurative cholangiohepatitis may have an excellent response to therapy, return to normal and have no recurrence of the disease. If the cat is severely ill and debilitated at the time of diagnosis, however, the long-term outlook can be poor with suppurative cholangiohepatitis. With nonsuppurative disease, chronic, long-term remission is possible, although some affected individuals succumb to the disease regardless of appropriate therapy. The prognosis is usually worse if biliary cirrhosis is diagnosed, as the presence of scar tissue can indicate the liver has a poor capacity for recovery.