The most common cause of biliary cirrhosis in dogs and cats is chronic EHBDO due to obstructive neoplasia. Biliary cirrhosis is uncommon in cats with chronic cholangitis/cholangiohepatitis because these animals usually die from the effects of progressive ductopenia. Biliary cirrhosis is commonly misidentified in animals with ductal plate malformations.
Clinical features of biliary cirrhosis include variable inappetence, cachexia, jaundice, normal to altered liver size (normal, small, or large in cats), coagulopathy, and ascites. Animals with chronic EHBDO may display acholic feces and a surprisingly robust appetite (reflecting absence of enteric bile acids impacting digestion) until liver injury is at end stage. Clinicopathologic features include hypoalbuminemia, hyperglobulinemia, hyperbilirubinemia, variable liver enzyme activities, hypocholesterolemia at end stage or hypercholesterolemia in EHBDO before end stage, and coagulopathies. Liver enzymes may be normal or increased, depending on the underlying causal disease.
In conditions with progressive immune-mediated or suppurative destructive cholangitis evolving widespread ductopenia, liver enzymes decline and may normalize with loss of targeted antigens and biliary structure. The liver may be considered large on abdominal radiographs in cats. Abdominal ultrasonography discloses nodular hepatic parenchyma with mottled hyperechogenicity, an irregular liver margin, abdominal effusion, and acquired portosystemic shunts (with color-flow Doppler). As chronic EHBDO progresses to biliary cirrhosis over ~6 months, evidence of EHBDO may also be obvious. Presinusoidal and sinusoidal portal hypertension may cause the gallbladder wall to appear edematous (thick).
Biopsies are needed for definitive diagnosis of biliary cirrhosis. Coagulopathy complicates tissue sampling and necessitates vitamin K1 supplementation and fresh frozen plasma transfusions before procedures. Treatment is supportive, requiring management of hepatic encephalopathy, hypoalbuminemia, EHBDO, and ascites.
Prognosis is generally poor as this diagnosis reflects a chronic disease process. Although cholecystoenterostomy or choledochoenterostomy can bypass EHBDO that has caused biliary cirrhosis, it introduces risk for chronic or recurrent retrograde bileborne infections. Extensive liver remodeling will not improve.
