Clinical Findings
The incidence of chronic hepatitis makes up approximately one fourth of the cases having liver biopsies at Colorado State
University (based on a review of 150 consecutive liver biopsies). Chronic hepatitis is more common in female dogs. The average
of presentation ranges from 4 to 10 years. It is interesting to note that in both our series and in studies by others it is
uncommon to observe chronic hepatitis/cirrhosis in dogs older than 10 years of age. As a general rule old dogs (> 11 years
of age) don't generally present with chronic hepatitis/cirrhosis or if they do they are at or near end stage disease.
The clinical signs parallel the extent of hepatic damage. Early in the disease there are usually no or minimal clinical signs.
Only after the disease progresses do the clinical signs specific for liver disease becomes evident. Frequent early signs are
gastrointestinal associated with vomiting, diarrhea and poor appetite or anorexia. Ascites, jaundice and hepatic encephalopathy
may then occur as the disease progresses. With development of these late signs the long-term prognosis is generally poor.
The laboratory findings include consistently elevated ALT and ALP. The magnitude of rise need not be marked however. One report
found 75% of the cases with abnormal bilirubin elevation (mean elevation of 2.6 mg/dl). Serum proteins are variable. As the
lesions become more severe albumin levels decline. Serum bile acids are abnormal in most cases having significant chronic
hepatitis and measurement of bile acids appear to be a good screening test for the patient with unexplained elevations in
ALT and ALP. In our study all dogs evaluated with chronic hepatitis had abnormal bile acid concentrations. In a second study
only 8/26 dogs with chronic hepatitis had normal fasting bile acids. However, postprandial samples were not determined in
these cases. Determining postprandial bile acids has been shown to increase the sensitivity of this test.
A presumptive diagnosis is made based on the clinical features and persistent increases of ALP and ALT values. A definitive
diagnosis requires a hepatic biopsy showing characteristic morphological patterns. Needle aspirates are not helpful in making
the diagnosis of chronic hepatitis because it is important to see the architecture of the liver and location and extent of
the inflammation. One must work with the pathologist when making the diagnosis of chronic hepatitis and to be certain that
characteristic abnormalities found in chronic hepatitis are present
Prognosis
There is little information of the prognosis with and without therapy. The prognosis in dogs with advanced chronic hepatitis
and cirrhosis is guarded. In a study by Strombeck found mean survivals ranging from 6 to 16 months with therapy. This study
also identified that dogs with hypoalbuminemia, hypoglycemia and coagulopathies have very guarded prognostic factors and many
died within 1 week of diagnosis. A second study of 79 dogs found that dogs with cirrhosis had a survival of less than one
month and dogs with chronic hepatitis had a mean survival in the range of about 20 to 30 months. Most of these dogs were not
advanced in their disease and had concurrent corticosteroid treatment.
Therapy
The management for chronic hepatitis involves removing the primary etiology. Short of treating the primary etiology all other
therapies suggested are unproven in the management of chronic hepatitis in dogs. We are still waiting for good clinical studies
proving efficacy in treatments. Such studies are hindered even from the start owing to the multiple etiologies of hepatitis
and the inconsistent histological descriptions. To date we have only limited case studies and clinical impressions of efficacy
in the management of chronic hepatitis.
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