Inflammatory Liver Diseases in Cats

Inflammatory liver diseases comprise the second most common cause of liver disease in cats. The two major forms of inflammatory liver disease described in North America are cholangiohepatitis (acute and chronic forms) and lymphocytic portal hepatitis. Signalment, clinical signs, clinical laboratory data, and ultrasonography can be used to establish a presumptive diagnosis of inflammatory liver disease; however, hepatic biopsy is needed for definitive diagnosis. Differences in treatment strategies for cholangiohepatitis and lymphocytic portal hepatitis warrant establishing a definitive diagnosis. Prognosis for long-term survival is good for cats that survive the first 2 to 3 months after diagnosis of either of these diseases. In North America, major causes of feline liver disease include the following: n Hepatic lipidosis—50% of cases n Inflammatory liver disease—25% n Malignant lymphoma—5% n Carcinoma—4% Terminology used to describe inflammatory liver diseases of cats can be confusing. These terms include suppurative or acute cholangiohepatitis, chronic cholangiohepatitis, chronic progressive nonsuppurative cholangiohepatitis, pericholangiohepatitis, chronic lymphocytic cholangitis, progressive lymphocytic cholangitis, sclerosing cholangitis, lymphocytic-plasmacytic cholangitis/cholangiohepatitis, lymphocytic cholangitis/cholangiohepatitis, lymphocytic portal hepatitis, and biliary cirrhosis. Some authors have preferred to use the general term cholangiohepatitis complex or cholangiohepatitis/cholangitis complex. Recent retrospective studies have clarified the classification of these diseases into acute cholangiohepatitis, chronic cholangiohepatitis, and lymphocytic portal hepatitis. TYPES OF INFLAMMATORY LIVER DISEASE Although there is no universally accepted classification of inflammatory liver disease in cats, a classification scheme based on histopathologic features is gaining support. Two major types of inflammatory liver disease have been described based on distinct histopathologic features: cholangiohepatitis (acute and chronic forms) and lymphocytic portal hepatitis. Another syndrome that may CE n Signs of inflammatory liver disease in cats can mimic those of other liver conditions. n Establishing a definitive diagnosis is important because approaches