Cholangitis/Cholangiohepatitis Syndrome

OVERVIEW • The liver is the largest gland in the body; it has many functions, including production of bile (a fluid substance involved in digestion of fats); bile ducts begin within the liver itself as tiny channels to transport bile—the ducts join together to form larger bile ducts and finally enter the extrahepatic or common bile duct, which empties into the upper small intestine; the system of bile ducts is known as the ―biliary tree‖ • The gallbladder is the storage unit for bile; bile is stored until it is needed for fat digestion • ―Cholangitis‖ is inflammation of the bile duct or the biliary tree • ―Cholangiohepatitis‖ is inflammation of biliary structures and surrounding liver tissue • Cholangitis/cholangiohepatitis syndrome occurs more commonly in cats; it is classified as ―suppurative‖ or ―nonsuppurative‖ (lymphoplasmacytic, lymphocytic), ―granulomatous,‖ or ―lymphoproliferative‖ (transition to lymphoma) based on microscopic examination of biopsy samples • ―Suppurative‖ refers to the presence of pus in the affected tissue; ―nonsuppurative‖ refers to an inflammatory process that is not characterized by the presence of pus—in cholangitis/cholangiohepatitis syndrome, the inflammatory process is characterized by the presence of lymphocytes and plasma cells (so-called ―lymphoplasmacytic‖ disease) or lymphocytes (so-called ―lymphocytic‖ disease); lymphocytes are a type of white blood cell that are formed in lymphatic tissues throughout the body—lymphocytes are involved in the immune process; plasma cells are specialized white blood cells; plasma cells are lymphocytes that have been altered to produce immunoglobulin, an immune protein or antibody necessary for fighting disease • ―Granulomatous‖ refers to nodular, inflammatory lesions; ―lymphoproliferative‖ refers to conditions in which an excessive number of lymphocytes are produced; ―lymphoma‖ is a type of cancer that develops from lymphoid tissue, including lymphocytes, a type of white blood cell formed in lymphatic tissues throughout the body