The liver is responsible for producing many of the proteins involved in the normal blood clotting process. These proteins are called factors VII, IX, X, and XI in Roman numerals. When the liver is severely diseased, these proteins are not produced in normal amounts and spontaneous bleeding may occur. For liver function to be affected enough that the production of these proteins is diminished, the underlying liver disease must be serious. Diseases of the liver cause widespread damage including toxins, inflammation, cancer, and terminal scarring or cirrhosis.

The underlying liver disease may cause decreased appetite, fever, weight loss, lethargy, vomiting or diarrhea. Some dogs with significant liver dysfunction become jaundiced, with yellow discoloration of the skin, the gums and the white parts of the eye. If liver disease is significant enough to cause bleeding, the dog may have bruising of the skin and gums and whites of the eye. Urine may be a dark yellow-orange if jaundice is present.

In dogs with liver disease, liver blood tests are usually elevated, and other blood tests may also be abnormal. Your veterinarian may recommend additional liver function tests, such as bile acids or blood ammonia levels. If a bleeding disorder is suspected, your vet may perform a coagulation panel of several different clotting tests or an ultrasound of the liver to evaluate any structural changes. A liver biopsy may be performed to determine the underlying cause of the liver disease.