One of the most important organs in the body, the liver is specially designed to perform many essential functions. However, its distinctive characteristics and activities render it susceptible to damage from a variety of sources, and such damage can have an enormous impact on a person’s health. Careful assessment of the nature and extent of liver disease is a necessary prerequisite to determine the most appropriate and effective treatment.
Albumin [al BYOO min]: a protein in the serum that transports substances such as drugs and prevents leakage of fluid into the surrounding tissues.
Alkaline phosphatase [AL kuh lin FAHS fah tays]: a protein found in bile duct cell membranes; blood levels may be increased in any liver disease, but more markedly with cholestasis.
Alhph 1 – antitrypsin [AL fah -1 an tigh TRIP sin]: plasma protein produced by the liver that inhibits the activity of trypsin and other proteolytic enzymes; inherited deficiency leads to emphysema and sometimes cirrhosis.
Aminotransferase [ah MEE noh TRANS fir ays]: hepatocyte enzyme that modifies proteins; blood levels increase in the setting of hepatocellular necrosis (hepatocyte death). The two aminotransferases important in liver disease are AST (aspartate aminotransferase) and ALT (alanine aminotransferase).
Antibodies: proteins produced in response to a specific antigen, which can then combine with that antigen and neutralize it.
Antigens: a molecule with a specific configuration that is recognized by the immune system; usually part of a protein or sugar. It stimulates the formation of a specific antibody and can elicit an allergic reaction, or otherwise trigger an immune response.
Ascites [uh SIGH teez]: accumulation of fluid in the abdominal cavity, usually secondary to liver scarring and increased sinusoidal pressure. Intractable ascites is unresponsive to treatment and continually recurs.
Autoimmunity [AW toh im MEWN it ee]: a state or disease in which the body’s immune system attacks the body’s own tissues.
Bile: greenish fluid formed by the liver and emptied into the small intestine via the bile ducts; contains bilirubin, bile salts, phospholipids, and cholesterol.
Bilirubin [BIL ee roo bin]: a bile pigment cleared from the bolld by the liver; formed as a breakdown product of old red blood cells; marked increase in blood levels can lead to jaundice from deposition of bilirubin in skin, mucous membranes, and whites of the eyes.
Caput medusae [KAP ut muh DOO see]: literally “Medusa’s head”; dilated, varicose veins around the umbilicus, which may be seen in patients with cirrhosis of the liver.
Ceruloplasmin [suh ROO loh PLAZ min]: copper transporter protein; blood levels are usually decreased in Wilson’s disease.
Cholestasis [hoh luh STAY sis]: blockage or suppression of bile flow, from either intrahepatic or extrahepatic causes.
Cirrhosis [sur ROH sis]: pathologically-defined disease characterized by diffuse, irreversible fibrosis of the liver surrounding regenerative nodules.
Coagulopathy [koh AG yoo LAH puh thee]: increased bleeding tendency due to decreased hepatic synthesis of clotting factors.
Decompensation: failure of the liver to compensate for damage or injury, resulting in a decrease in liver functions.
Dysplasia [dis PLAY zhuh]: alteration in size, shape, and organization of cells; may be precursor of cancer.
Encephalopathy [en SEF uh LAH puh thee]: alteration in sleep patterns and mental status, ranging from forgetfulness and mild confusion to coma; may be caused by circulating gut-derived brain-toxic proteins not cleared by a dysfunctional liver.
Fibrosis [figh BROH sis]: the formation of fibrous tissue, or scarring.
Fulminant: running a speedy course, with rapid worsening.
Hemochromatosis [HEE moh KROH mah TOH sis]: toxic accumulation of iron in organs leading to dysfunction, including cirrhosis; may be genetic (inherited increase in gut iron absorption) or a result of massive blood transfusions.
Hepatitis [HEP uh TIGH tis]: inflammation and damage to the liver; generally considered acute if duration is less than 6 months, chronic if greater than 6 months.
Hepatocellular necrosis: localized tissue death of hepatic cells.
Hepatocellular carcinoma (HCC): a primary liver tumor more common in patients with cirrhosis.
Hepatocytes: liver cells.
Hepatorenal [HEP uh togh REE nahl] syndrome: poorly understood terminal kidney failure in the setting of hepatic disease.
Homeostasis [HOH mee oh STAY sis]: tendency of the body to maintain a stable internal environment, using a variety of counterbalancing control systems.
Hyperbilirubinemia [HIGH pur BIL ee roo bin EE mee uh]: abnormally high levels of bilirubin in the blood.
Icterus: see Jaundice.
Idiopathic [ID ee oh PATH ik]: autoimmune chronic active hepatitis (IACAH): chronic hepatitis of unknown origin; associated with a variety of anti-self antibodies; progresses to cirrhosis and decompensation unless treated with corticosteroids.
Jaundice [JAHN dis]: hyperbilirubinemia, with deposition of bile pigment in the skin, mucous membraes, and sclerae (whites of eyes), resulting in a yellow appearance of the patient; also called icterus.
Kayser-Fleischer rings: golden-brown rings in the corneas due to copper deposition in Wilson’s disease.
Kupffer cells: “scavenger” cells that remove foreign matter, worn-out blood cells, and bacteria from the liver.
Limiting plate: layer of hepatocytes surrounding each portal triad and separating it from the surrounding sheets of hepatocytes.
Lobule [LAHB yool]: “structural” unit of the liver; shaped like a hexagon on cross section, with six portal triads at the periphery and a central vein.
Portal hypertension [POR tahl HIGH per TEN shun]: abnormal increase in portal blood pressure, usually due to obstruction of, or increased resistance to, portal blood flow.
Portal system: includes all the veins that drain the small and large intestines, stomach, and spleen and that converge into the portal vein to drain into the liver.
Portal triad (or tract): consists of three components: branch of the hepatic artery, branch of the portal vein, and a biliary duct, all held tightly together by a limiting plate of hepatocytes at the periphery of the lobule.
Portosystemic [POR toh sis TEM ick] shunting: development of blood vessels that connect the portal and systemic circulation while bypassing the liver.
Prognosis: prediction as to the probable outcome of a disease.
Prothrombin [proh THRAHM bin] time (PT): laboratory test that measures the clotting of blood in seconds; abnormally increased PT signifies bleeding risk due to deficient synthesis of clotting proteins.
Seroconversion: appearance of specific antibodies in the blood, indicating recovery from infection or successful vaccination.
Sinusoids: tunnels through hepatic tissue allowing exchange of nutrients and other substances between blood and hepatocytes.
Spider angiomas: red capillary tufts in the skin that blanch on pressure; often found in patients with cirrhosis.
Spontaneous bacterial peritonitis (SBP): bacterial infection of ascitic fluid.
Steatorrhea [STEE uh toh REE uh]: decreased absorption of dietary fats, resulting in their passage to the distal bowel which causes foul-smelling diarrhea; can be caused by deficiency of bile salts.
Transaminase: see Aminotransferase.
Varices [VAYR ih seez]: dilated veins; lower esophageal varices form as collaterals from portal hypertension and can rupture, leading to massive bleeding.
Wilson’s disease: inherited metabolic disorder in which copper accumulates in the liver and in the central nervous system, causing hepatitis, cirrhosis, and neuropsychiatric symptoms.