Depending on the severity and underlying cause of liver disease, a nonregenerative or regenerative anemia may develop. Severe or acute anemia can impact the liver as a result of hypoxia, causing alterations in hepatocyte membranes, leading to release of transaminases and induction of AP. Altered RBC morphology (poikilocytes, irregularly irregular RBC) is common in cats with cholangiohepatitis and hepatic lipidosis (HL). Cats with HL, severe cholangiohepatitis, and EHBDO also may develop Heinz bodies that lead to hemolysis. Severe hypophosphatemia in HL develops secondary to a re-feeding syndrome that can cause hemolysis severe enough to require a blood transfusion; this can be avoided by using fluid therapy supplemented with potassium phosphate. Dogs with diffuse necroinflammatory liver disease (altered sinusoidal perfusion) can have RBC demonstrating microvascular shearing (eg, schistocytes). RBC microcytosis is common in congenital or acquired portosystemic shunting.
Changes in WBC count and distribution are variable. Leukocytosis may reflect inflammatory, infectious, necrolytic, or diffuse infiltrative neoplastic lesions within the liver, or release of endogenous or therapeutic glucocorticoids. Leukopenia can reflect sepsis or toxicosis. In severe diffuse necroinflammatory liver injury, damaged sinusoidal microvasculature can provoke platelet aggregation, contributing to thrombocytopenia and disseminated intravascular coagulation.
Last full review/revision March 2012 by Sharon A. Center, DVM, DACVIM