Cholangitis-Cholangiohepatitis Syndrome in Dogs
Inflammation of the bile ducts and intrahepatic ducts -- the ducts that carry bile out of the liver -- is medically referred to as Cholangitis. Bile, an essential component in the digestive process, begins in the liver and is then stored in the gallbladder until a meal is taken. The bitter fluid is then released into the dog's small intestine, where it emulsifies fats in the food to be used as energy by the rest of the body.
Cholangiohepatitis, meanwhile, describes inflammation of the bile ducts and liver. Together, these diseases are referred to as Cholangitis-Cholangiohepatitis Syndrome (CCHS). This disease is rare in dogs, but is well documented in the cat population.
Symptoms and Types
Certain conditions often occur prior to or simultaneous to CCHS: inflammation or clogging of the liver ducts running outside the liver (EHBDO), inflammation of the pancreas, inflammatory bowel disease (IBD), fatty liver disease, or long-term inflammation of kidney tissue. Symptoms may be sudden, intermittent, or long-term.
However, there are currently only three types of CCHS are recognized: suppurative, which has a discharge of fluid within the biliary canal and is often sudden onset, but generally has a good outcome; nonsuppurative, which is reoccurring and has a guarded to poor prognosis; and lymphocytic/lymphoplasmacytic, where lymphocytes and plasma cells invade and surround the liver's portal vein or portal triad (the portal vein, bile duct and artery of the liver), and which has a poor outcome due to its longer lasting chronic nature and tendency to progress to cirrhosis of the liver.
Suppurative CCHS
- Fever
- Swollen painful abdomen – due to fluid crossing over into the abdomen (ascites)
- Yellow skin and yellow whites of eyes
- Dehydration
- Shock
Nonsuppurative CCHS
Causes
Suppurative CCHS
- Infectious:
- Campylobacter
- Salmonella
- Leptospirosis
- Non-infectious:
- Happens after EHBDO (extra-hepatic bile duct obstruction)
- Happens after gall bladder blockage
Nonsuppurative CCHS
- May not be directly causal, but concurrent with:
- EHBDO
- Inflammation of gallbladder
- Gallstones
- Inflammation of the pancreas
- Inflammatory Bowel Disease
- Long-term swelling of kidney tissue
Diagnosis
Your veterinarian will perform a thorough physical exam on your dog, taking into account the background history of health, onset of symptoms, and possible incidents or illnesses that might have led to this condition. Some of the factors that place a dog at risk for developing CCHS are inflammatory bowel disease, pancreatitis, or obstruction of the bile ducts outside of the liver.
A chemical blood profile, complete blood count and urinalysis will be taken. These may reflect anemia, high liver enzymes, bilirubinuria (bilirubin in the urine), and/or lymphocytosis. They might also reflect cancer if it is causing the swelling of the liver and/or gallbladder. Often, sludged bile is found, which may be the cause of blocked bile ducts.
If your veterinarian suspects swelling of the pancreas, a TLI blood test (trypsin-like immunoreactivity – a pancreatic digestive enzyme) can be taken to test for pancreatic sufficiency. Vitamin B12 levels will be tested; low values indicate absorption problems in the small intestine, or pancreatic problems. Coagulation tests will also be performed to verify whether the blood is clotting normally. And thyroxine, a thyroid gland, may be tested to rule out a thyroid tumor.
Chest X-rays, abdominal X-rays and an abdominal ultrasound can be used to check for cancer and to visualize the liver, pancreas and kidneys. For a closer visual exam, a laparotomy may also be performed. This method uses a diagnostic tool called a laparoscope, a small, flexible instrument that is passed into the body through a small incision. The laparoscope is equipped with a small camera and biopsy forceps, so that you doctor can visually inspect the walls and ducts of the liver and pancreas, and take a sample for biopsy. For further laboratory analysis, abdominal fluid and cell samples may sometimes be taken.
Treatment
If your dog has suppurative CCHS, antibiotics will be given. For nonsuppurative CCHS, immune-modulating drugs and antibiotics may be given. If your dog has lymphoma (cancer of the lymphocyte white blood cells), chemotherapy may also be considered. Antioxidants may be prescribed along with other drugs to protect the liver. Vitamin B and E supplements are recommended, as well as vitamin K, which may be used if blood clotting times are not normal.
In some cases, surgery may be indicated, such as when an obstruction in the bile ducts is preventing bile from flowing normally. For milder cases, your dog may be treated on an outpatient basis, but if dehydration or malnutrition is found to be affecting your dog, or if your dog is unable to eat or drink, it will need to be placed on a feeding tube and intravenous line until its condition stabilizes.
Treatment will take about three to four months, with liver enzymes checked every two weeks. If the treatment does not appear to be working after four weeks, your veterinarian will need to repeat a bile culture and take a biopsy of liver tissue and fluid for analysis.
Living and Management
You will need to return for regular check-ups with your veterinarian, especially if signs suddenly occur again or if signs worsen.
For nonsuppurative CCHS, lifelong immunomodulatory, antioxidant, and hepatoprotective therapy is often recommended. You should restrict your dog's activity during the recovery period, and your veterinarian will help you to create an easily digestible, high protein meal plan for the dog. Your veterinarian may also suggest that you supplement your dog's diet with water-soluble vitamins.
Moreover, if your dog has inflammatory bowel disease or swelling of the pancreas as well, it may need to be fed a more specialized diet.