That little white powderpuff of a dog known as the bichon frise doesn't suffer from as many genetic abnormalities as many toy breeds. However, Precious might be born with liver shunt, also known as portosystemic shunt. Certain bichon lines are more likely to be affected than others.
The portal vein carries blood to the liver for cleansing. If your bichon is born with a portosystemic shunt, that means unclean blood bypasses the liver and gains direct access to his vascular system, according to the Merck Veterinary Manual. One shunt may be present, or several. In small dogs, liver shunt is usually extrahepatic, meaning that small shoots of the animal's portal vein occur outside his liver. Basically, it means unfiltered blood circulates throughout his body, exposing him to toxins that normally are filtered out.
Many puppies born with liver shunt die within a few weeks. Others grow up and don't show symptoms until they are a few years old. Sometimes symptoms appear because your dog begins experiencing major liver problems. Liver shunt symptoms include gastrointestinal problems, seizures and behavioral changes. An affected bichon might be smaller than normal and unusually quiet. If your dog undergoes surgery, perhaps for a spay or neuter, it might take her an exceptionally long time to recover from the anesthesia.
Diagnosis and Treatment
After physically examining your bichon and conducting blood and bile tests, your vet performs an ultrasound to view the liver. She can then see the location of the shunt or shunts and determine how many exist. If your dog is mildly affected, your vet might prescribe a special diet and supplements to detoxify your pet, along with antibiotics. More serious cases require surgical correction. Because the surgery is quite complicated, it might not be something your regular vet can do. In that case you'll have to take your dog to a specialist.
Hepatic Microvascular Dysplasia
A rare but related genetic liver problem found in bichons, hepatic microvascular dysplasia might or might not produce symptoms. Your dog might have this condition alone or in conjunction with a liver shunt. Symptoms include vomiting and diarrhea, appetite loss and lethargy. If your dog doesn't show symptoms, your vet might suspect it when receiving results from routine diagnostic tests, such as high liver enzyme levels and excess ammonia in the urine. Treatment is the same as for liver shunt.
- Bichon Frise Club of America: Liver Shunt aka Portosystemic Shunt
- Canine Health Information Center: Bichon Frise
- The Merck Veterinary Manual: Congenital and Inherited Anomalies of the Liver
- Veterinary Surgical Specialists: Portosystemic Shunt and Hepatic Microvascular Dysplasia
- petMD: Genetic Liver Abnormality in Dogs
- University of Tennessee Institute of Agriculture: Portosystemic Shunts
- Comstock/Comstock/Getty Images