Glossary
Acute—Any condition that is severe and sudden in onset.
Acute hepatitis C—The initial stages of hepatitis C infection; the acute phase of infection can last up to 6 months. Some people may experience jaundice (yellowish eyes and skin that occurs as a result of the liver becoming inflamed), fatigue, nausea, and increases in serum ALT levels. A small percentage of people with acute hepatitis C are able to clear the virus naturally from the bloodstream and recover on their own. However, more than 80% develop chronic (long-term) hepatitis C.
Alanine aminotransferase (ALT)—An enzyme that is found mainly in the liver and in other tissues of the body. When the liver is damaged, this enzyme is released into the bloodstream. ALT levels can be measured to determine if the liver is damaged or diseased.
Alcoholism- An illness marked by consumption of alcoholic beverages at a level that interferes with physical or mental health, and social, family, or occupational responsibilities.
Alopecia—Thinning or loss of hair.
Anorexia—A decreased appetite or aversion to food.
Antibody—A protein produced by the immune system in response to the presence of an antigen (foreign substance). It defends the body against substances identified by the immune system as potentially harmful.
Antigen—A substance that triggers an immune response because the body recognizes it as foreign (different from normal body components).
Antigenic—Provoking an immune response or reacting with specific antibodies.
Anti-inflammatory—Counteracting or suppressing inflammation.
Antiviral—A substance that fights viruses.
Arthralgia—Joint pain.
Ascites—An abnormal buildup of fluid in the abdomen usually due to cirrhosis and portal hypertension.
Assay—A test that identifies either antigens or antibodies to diagnose an infection.
Autoimmune disorders—Conditions in which the immune system mistakenly identifies cells of the body as foreign material, producing an immune response against the body itself.
Bacteria—Tiny organisms that often form colonies and live in soil, water, organic matter, or the bodies of plants and animals. While not all bacteria are harmful, some cause disease.
Bile—A yellow-green fluid that is made by the liver to help digest fat. The principal components of bile are cholesterol, bile salts, and the pigment bilirubin.
Blood-borne virus—A virus that circulates in the blood and can be transmitted from one person to another during blood-to- blood contact (eg, through shared needles).
Branched DNA signal amplification—A laboratory test that can detect the genetic material (DNA) of a virus in a blood sample, and quantify how much of that genetic material is present.
Chronic—A condition that frequently recurs or continues for a long time.
Chronic hepatitis C—A persistent hepatitis C infection with periodic evidence of HCV RNA in the blood for at least 6 months. The diagnosis is usually made by blood tests showing detectable viral levels in the blood.
Cirrhosis—A condition in which the liver does not function normally due to scarring. Healthly liver cells are replaced with non-functioning scar tissue. Alcohol accounts for approximately 50% of all cases.
Community-acquired infection—An infection that occurs through contact with an infectious agent in the community.
Compensated liver disease—Advanced liver disease that is stabilized.
DNA (deoxyribonucleic acid)—The abbreviation for deoxyribonucleic acid, the genetic material of nearly all forms of life. DNA is used to store the genetic information of all living creatures.
Elevated liver enzymes—The presence of abnormal blood serum levels of liver enzyme as a result of some for of injury to the liver. Liver enzymes are special proteins found in liver cells responsible for triggering various metabolic reactions.
Enzyme—A protein molecule in a plant or animal that causes specific biochemical reactions in every stage of metabolism. For example, certain enzymes aid in digestion.
Enzyme Linked Immunosorbent Assay (ELISA)—An immunoassay is a test in which a substance is identified by its ability to produce an immune response (by binding to specific antibodies). In an enzyme immunoassay, an enzyme is used to highlight or label either the substance in question or the antibody that is produced in response to it.
Exposure—Coming in contact with infectious agents (bacteria or viruses).
False-positive—Test result that incorrectly indicates the presence of a disease. Certain tests have higher false-positive rates than others.
Fatigue—Feelings of being very tired or lacking energy.
Fibrosis—Scarring of the liver.
Fulminant hepatic failure—Acute liver failure resulting from some injury to the liver resulting in the development of hepatic encephalopathy within six weeks. This form of liver failure is associated with a high rate of death.
Gastroenterologist—A doctor who specializes in disorders of the stomach, intestines, and all related organs, including the liver.
Genotype—A unique set of genetic information that codes for and determines specific characteristics about an organism. There are 6 known major genotypes of the hepatitis C virus, some of which are more prevalent in specific parts of the world.
Half-life—The time required for half the amount of a substance (such as a drug or toxin) introduced into the body to be eliminated by the body through natural processes.
HCV—The abbreviation for the hepatitis C virus.
HCV RNA—The abbreviation for hepatitis C virus ribonucleic acid. RNA is the genetic material of hepatitis C virus and is a chemical that is very similar to DNA. The hepatitis C RNA contains the information that the hepatitis C virus needs to function.
Hemodialysis—A medical procedure that uses a special machine (a dialysis machine) to separate and cleanse the blood.
Hepatic—Relating to the liver.
Hepatitis—Any inflammation of the liver.
Hepatitis A—Liver disease caused by the hepatitis A virus, contracted through food or water contaminated by fecal matter. The hepatitis A virus belongs to the Picornaviridae family of viruses.
Hepatitis B—Liver disease caused by the hepatitis B virus, passed through sexual activity or contact with infected blood or blood products. The hepatitis B virus belongs to the Hepadnaviridae family of viruses.
Hepatitis C—Liver disease caused by the hepatitis C virus, passed through contact with infected blood or blood products. The hepatitis C virus belongs to the Flaviviridae family and the Hepacivirus genus of viruses.
Hepatocyte—Special cells found in the liver.
Hepatologist—A doctor who specializes in liver diseases.
Histologic response—Improvement in the liver due to a reduction in inflammation.
Histology—The study of tissue under a microscope.
Immunocompromised—A situation where the immune system is weakened or not functioning normally because of illness or an immunosuppressive agent.
Inflammation—An immune system response to infection, irritation, or other injury, which usually results in redness, warmth, swelling, and pain in the affected area.
Immunoregulatory—Controlling immune response functions.
Insomnia—Inability to sleep.
Interferon—A protein that is secreted by cells in the body as a response to viral infections. Alpha interferon is one specific type of this protein. It was genetically engineered to be used in the treatment of viral hepatitis and other viral diseases.
Invasive—Any procedure involving entry into the living body, including entry by incision or insertion of an instrument.
Jaundice—A yellowing of the skin, whites of the eyes, tissues, and certain body fluids, which can result from certain liver diseases, including hepatitis C, or from excessive breakdown of red blood cells due to internal hemorrhage or various other conditions.
Liver—A large, dark-red organ in the human body located in the mid-abdomen region. The liver performs many important functions, such as processing food into fuel for the body and cleaning alcohol and poisons from the blood.
Liver biopsy—A tiny sample of the liver is removed (with a needle) and examined in a laboratory.
Liver cancer—A malignant tumor of the liver. Contributing factors to the development of liver cancer include viral hepatitis; chronic liver disease; hemochromatosis (an inherited liver disease that affects how the body processes iron); known liver carcinogens; and toxins (mycotoxins) found in foods in parts of Africa and Asia. Avoiding known liver carcinogens and preventing and treating viral hepatitis may be beneficial in reducing the risk of liver cancer.
Liver failure—A condition of severe end-stage liver disease, which is accompanied by a decline in mental status that may range from confusion to coma. Other features include tremor (shaking movements resulting from involuntary contracting and relaxing of muscles) and gastrointestinal bleeding, with vomiting of blood or blood in the stool.
Liver inflammation—A biological response to cellular injury that may affect liver function.
Lymphocytes—White blood cells that play a role in defending the body against disease.
Malaise—A feeling of weakness or discomfort.
Metabolism—The process in which the body breaks down or builds carbohydrates, fats, and proteins for use as a source of energy.
Metabolic reactions—Processes and chemical changes in living cells by which energy is provided for vital functions.
Monotherapy—Therapy with one drug or agent.
Myalgia—Muscle pain.
Neutropenia—An abnormal decrease in the number of neutrophils, types of white blood cell. If present, individuals may be at risk for infections.
Noninvasive—Any procedure that does not involve penetration (as by surgery or hypodermic needle) of the skin.
Pegylation—A process that helps proteins, including interferon, remain in the body longer.
Polymerase Chain Reaction (PCR)—A testing technique that can identify the DNA or RNA (ie, the primary genetic material) of a specific organism. This type of test can identify hepatitis C virus RNA in a blood sample, and is the most specific test for hepatitis C infection.
Protein—Molecules involved in structures, hormones, enzymes, muscle contraction, and immune system responses.
Pyrexia—Fever.
Qualitative HCV Polymerase Chain Reaction (PCR)—A
testing technique that can identify the DNA or RNA (ie, the
primary genetic
material) of a specific organism. This type of test can identify hepatitis C
virus RNA in a blood sample, and is the most specific test for hepatitis C
infection.
Recombinant Immunoblot Assay (RIBA)—A qualitative test used to detect antibodies to specific antigens. In testing for antibodies to hepatitis C, RIBA has historically been used to confirm results of a positive enzyme linked immunosorbent assay (ELISA).
Ribonucleic Acid (RNA)—The abbreviation for ribonucleic acid, a form of genetic material. Life forms (with the exception of some viruses) use RNA as a temporary messenger molecule to carry information that is permanently stored in DNA.
Ribavirin—A medication, often prescribed with alpha interferons, to make the alpha interferon more effective against the hepatitis C virus. It is taken as a capsule by mouth.
Serum—A clear liquid part of blood.
Solid Organ Transplant—An operation in which a vital organ of the body is surgically removed from one person and placed into another person. Solid organs that can be transplanted include: heart, lung, liver, kidney, pancreas, and intestine.
Spleen—An organ located near the stomach that stores blood, disintegrates old blood cells, filters foreign substances from the blood, and produces a type of immune cells called lymphocytes.
Sporadic infection—(In the context of hepatitis C) an infection in which the cause is unknown.
Sustained virologic response (SVR)—The virus remains at undetectable levels in the blood for 6 or more months after the end of treatment.
Transmission—The way a disease is transferred or spread from one person to another.
Universal precautions—A set of guidelines developed by the U.S. Centers for Disease Control intended to decrease the risk of spreading illness and disease in healthcare settings. Specifically, universal precautions are to be used when coming into contact with certain types of body fluids, such as blood, semen, and vaginal fluids. When handling these fluids, all measures to avoid exposure should be taken, including wearing gloves and other protective covers; avoiding injury; and proper disposal of affected materials.
Viral load—The amount of viral particles present in a milliliter (one-thousandth of a liter) of blood.
Virologic response—A reduction in the amount of virus in the blood to an undetectable level.
Virus—A micro-organism smaller than a bacteria, which can only grow and reproduce within living cells. Viruses cause many human infections, and are responsible for various diseases. Viruses can mutate, or change, in each infected person, which makes treatment more difficult.
White blood cells—Cells the body makes to help fight infection.