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Acute Hepatitis

A course of hepatitis (liver inflammation) that resolves in six months or less.


A person who works for the benefit and rights of others.


See alpha-fetoprotein.

Alanine Aminotransferase (ALT)

an enzyme found in liver cells and other cells of the body; measuring blood levels is an indicator of liver cell damage and/or death.


a protein made by the liver; blood levels are used to check liver function.


the intoxicating substance in beer, wine, and hard liquors; also found in some over-the-counter products such as mouthwashes and cold remedies; also known as ethanol.

alk phos

see alkaline phosphatase.

alkaline phosphatase

an enzyme found in nearly every tissue of the body but found in the highest concentrations in the liver and bones; elevated levels often indicated blocked bile flow either inside or outside the liver; also known as ALP.


see alkaline phosphatase.


a protein produced by liver cells normally found in only trace amounts in the body; the blood test for this substance is used to screen for liver cancer (hepatocellular carcinoma).


see alanine aminotransferase.

amino acid

one of a group of substances that are the building blocks of proteins.


referring to an anecdote (see below).


in medicine, an account of one person's experience usually with a particular treatment.


a condition in which the blood is deficient in red blood cells and/or hemoglobin; a condition that reduces the blood's ability to carry oxygen to the tissues.


a protein produced by the immune system usually in response to infecting organisms such as bacteria or viruses; antibodies are one way the immune system tries to rid the body of infection.


a protein that stimulates the immune system to produce antibodies; derived from the words '''antibody generator'''.

anti-HCV antibody

any of a number of antibodies produced by the immune system in response to the hepatitis C virus; the presence of these antibodies in the blood indicate that the person has been exposed to the hepatitis C virus; the screening test for hepatitis C (the anti-HCV test) detects these antibodies in the blood.


a substance that inhibits the chemical process called oxidation; in hepatitis C, antioxidants are used to limit damage done by high levels of free radicals present because of ongoing inflammation caused by the virus.


an agent that kills viruses or suppresses their replication (reproduction).


abnormal accumulation of fluid in the abdomen; a common complication of portal hypertension.

aspartate aminotransferase (AST)

an enzyme found in liver cells and other cells of the body; measuring blood levels is an indicator of liver cell damage and/or death.


see aspartate aminotransferase


without symptoms.


a condition characterized by the production of abnormal antibodies that attack the body's own tissues.

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see branched DNA test for HCV


a yellowish green fluid made by the liver from bile salts, bilirubin (broken-down red blood cells), cholesterol, and other substances; the fluid stored in the gallbladder; the fluid released from the gallbladder into the intestine to help fat digestion.

bile acids

a group of chemicals produced by the breakdown of cholesterol; levels are often abnormal with liver and/or gallbladder disease.


a yellow-orange substance generated in the liver from the breakdown of hemoglobin from old red blood cells; the substance that causes jaundice when blood levels are abnormally high; blood levels are one indicator of liver function.

conjugated bilirubin (direct bilirubin)

bilirubin that is attached to another chemical called glucuronic acid in a process called conjugation. Conjugation takes place inside liver cells. Conjugated bilirubin is excreted in the bile. Normally, conjugated bilirubin makes up less than 10% of the total bilirubin.

total bilirubin

the sum of both the conjugated and unconjugated bilirubin.

unconjugated bilirubin (indirect bilirubin)

Unconjugated bilirubin has not undergone the conjugation process in the liver. Normally, unconjugated bilirubin makes up over 90% of the total bilirubin.

bleeding esophageal varices

see varix.

blood serum

the liquid part of blood; the liquid that separates from blood when it clots completely.

blood sugar

see glucose.

body mass index (BMI)

a measure of a person's weight in proportion to height; an indicator of being over or underweight; calculated by dividing your weight (in kilograms) by your height in meters squared; a healthy BMI for adults is between 18.5 and 24.9.

branched DNA test for HCV (b-DNA)

test used to check for the presence of the hepatitis C virus in the blood; test used to check viral load.

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capable of causing cancer.


see complete blood count.


the use of chemical agents to treat or control disease; commonly refers to drugs used to kill cancer cells.


a lipid or fat that is both absorbed from the food we eat and manufactured by the liver; blockage of bile flow either inside or outside the liver increases the amount of cholesterol in the blood.

chronic hepatitis

a course of hepatitis (liver inflammation) that lasts more than six months.

CIA Chemiluminescence immunoassay

a screening test format for anti-HCV (e.g., VITROS Anti-HCV assay).


scarring of the liver that has progressed to the point that the structure of the liver is abnormal; the stage of liver disease that follows if there is progressive fibrosis.


in medicine, anything related to disease that can be observed or diagnosed in a patient.

clinical trial

process used to evaluate the effectiveness and safety of new medications, procedures, or medical devices by monitoring their effects on large groups of people; the testing usually required by the Food and Drug Administration before approving a new drug, procedure or medical device.

  • phase I trial: This is the first clinical trial for studying an experimental drug or treatment in humans. Phase I trials are usually small (10-100 people) and are used to determine safety and the best dose for a drug. These trials provide information about side effects, and how the body absorbs and handles the drug. People in these trials are usually healthy volunteers.
  • phase II trial: Phase II trials examine whether a drug or therapy is active against the disease it is intended to treat. Side effects are studied. A phase II trial is a noncomparative study, meaning the therapeutic effects and side effects of the experimental treatment are not compared to another drug or a placebo.
  • phase III trial: Phase III trials are conducted to find out how well a drug or therapy works compared to standard treatment or no treatment. Phase III trials are large studies and usually involve several hundred to thousands of patients.
  • controlled clinical trial: A controlled clinical trial divides participants into study groups to determine the effectiveness and safety of a new treatment. One group receives the experimental treatment; the other group receives placebo (an inactive substance) or the standard therapy. This group is called the control group. Comparison of the experimental group with the control group is the basis of determining the safety and effectiveness of the new treatment.

randomized clinical trial

A randomized clinical trial involves patients who are randomly (by chance) assigned to receive either the experimental treatment or the control treatment (placebo or standard therapy).

combination therapy

therapy that involves two or more components that can be drugs, procedures, or other specific treatments.

complete blood count (CBC)

a blood test that includes measurements of white blood cells, red blood cells, hemoglobin, hematocrit, platelets, and possibly others.


in medicine, a condition or other reason not to use a particular drug or treatment.


see contraindicate.

controlled clinical trial

see clinical trial.


the presence of abnormal antibodies called cryoglobulins in blood; the condition may lead to kidney damage, kidney failure, and a variety of other symptoms; this condition is commonly found in people with chronic hepatitis C.


abnormal blood protein formed when several antibody molecules (gamma globulins) clump together; protein in the condition cryoglobulinemia that can cause abnormal blood clots in the brain (stroke), eyes, and/or heart.


in hepatitis C, sustained viral clearance is considered a cure; undetectable hepatitis C virus in the blood for six or more months after the completion of treatment.

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in the liver, the inability of the liver to regenerate itself and compensate for damage it has sustained; liver damage that has progressed to the point that the liver functions begin to deteriorate.

delta hepatitis

see hepatitis, hepatitis D.

deoxyribonucleic acid (DNA)

the type of molecule that human genes are made of; the molecule that carries all genetic information in humans.


a mental condition characterized by apathy, lack of emotional expression, social withdrawal, changes in eating and sleep patterns, and fatigue; a mental condition that can accompany any life-changing event including being diagnosed with a chronic illness; a possible side effect of interferon/ribavirin therapy.


see glucose.


to swell out or expand from internal pressure; in hepatitis C, ascites causes distension of the abdomen.


see deoxyribonucleic acid.

durable response

see sustained response.

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EIA Enzyme immunoassay

a screening test format for anti-HCV (e.g., Abbott HCV EIA 2.0 and ORTHO HCV Version 3.0 ELISA).


see hepatic encephalopathy.


a substance produced in the brain, spinal cord, and other parts of the body that causes elevated mood, reduced pain, and reduced stress; the body's natural pain killer; a substance released by the body during exercise.


a protein that starts and/or propels a specific chemical reaction; commonly tested liver enzymes include ALT, AST, and GGT.

enzyme immunoassay (EIA)

one of the tests used to detect antibodies to HCV (anti-HCV antibody).


situated or originating outside the liver.

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Food and Drug Administration


a protein that binds iron; tested to check the amount of iron in the body.


in liver disease, the laying down of scar tissue in the liver; usually the result of ongoing inflammation.


a proprietary set of blood tests used together to differentiate no/mild liver fibrosis from severe fibrosis; this is not a substitute for liver biopsy but can possibly provide some useful information for people who cannot or do not wish to have a liver biopsy.


composed of or containing fibers; scar-like.


a vitamin A-like substance found in many fruits and vegetables; many flavinoids are powerful antioxidants.

free radical

a highly reactive chemical that oxidizes other chemicals in the body; the chemicals that cause oxidative stress in the body; the chemicals that cause oxidative damage in the body; chemicals normally produced in the body and neutralized by antioxidants; chemical produced in excessive amounts by chronic infection and/or inflammation.

fulminant liver failure

severe and rapidly progressive liver cell death.

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gamma globulin

see immune globulin

gamma-glutamyl transferase (GGT)

a liver enzyme (protein); blood GGT levels are measured to check for liver damage associated with slow or blocked bile flow; GGT is elevated in all forms of liver disease


a doctor who specializes in diagnosing and treating diseases of the digestive system including the liver.

gastroesophageal varices

see varix.


the material that encodes for all inherited traits and characteristics of a living thing; a piece of DNA (deoxyribonucleic acid) the carries the message for a particular trait or characteristic.


all the genetic information of a particular organism.


in hepatitis C, one of several different species of the hepatitis C virus; different genotypes have different responses to interferon-based therapy; different genotypes have some differences in the genes they contain.

genotype test

a test to identify the specific genotype of the HCV virus.


see gamma-glutamyl transferase.


see gamma-glutamyl transferase.


a kidney disease in which the filtering units of the kidney (the glomeruli) are damaged; the disorder is characterized by edema (swelling), elevated blood pressure, and excess protein in the urine.


the form of sugar found in the blood; the breakdown product of simple and complex carbohydrates that can be used by the body; also known as dextrose or blood sugar.

glutamate oxaloacetate transaminase

see aspartate aminotransferase.

glutamate pyruvate transaminase

see alanine aminotransferase.


see aspartate aminotransferase.


see alanine aminotransferase.


in liver biopsy, a term used to describe the amount of inflammation in the liver; the higher the grade, the greater the inflammation.

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see hepatitis, hepatitis A.


see hepatitis, hepatitis B.


see hepatocellular carcinoma.


see hepatitis, hepatitis C.

HCV antibody

see anti-HCV antibody.


see anti-HCV antibody.


see HCV polymerase chain reaction.

HCV polymerase chain reaction (PCR)

test to check for the presence of the hepatitis C virus in the blood; a qualitative HCV PCR test determines the presence or absence of virus in the blood; a quantitative HCV PCR test measures the amount of detectable HCV in the blood.


hepatitis C virus ribonucleic acid; the genetic material of HCV.


a hereditary disease caused by increased absorption and excessive storage of iron in the tissues, especially the liver; the untreated disorder can lead to cirrhosis of the liver, heart disease, diabetes mellitus, testicular atrophy, and arthritis.


the protein in red blood cells that carries oxygen.


a group of hereditary disorders characterized by abnormal hemoglobin structure; sickle cell anemia is an example.

hemolytic anemia

anemia due to increased destruction of red blood cells; can be a side effect of ribavirin therapy.


relating to the liver.

hepatic cell

see hepatocyte.

hepatic encephalopathy

a complication of liver failure that results from large amounts of ammonia that accumulate in the brain; symptoms include euphoria, depression, confusion, slurred speech, abnormal sleeping patterns, incoherent speech, tremors, rigid muscles, and eventually coma.


inflammation of the liver.

hepatitis A

a disease caused by the hepatitis A virus (HAV); transmitted by food or drink that has been contaminated by an infected person; symptoms include nausea, fever, and jaundice (yellowing of the skin and/or eyes); hepatitis A does not progress to chronic hepatitis.

hepatitis B

a disease caused by the hepatitis B virus (HBV); transmitted sexually or by contact with infected blood; hepatitis B may progress to chronic hepatitis and can be fatal.

hepatitis C

a disease caused by the hepatitis C virus (HCV) C; transmitted by contact with infected blood via contaminated needles and transfusion of infected blood products; rarely transmitted sexually; hepatitis C becomes chronic in 85% of people infected and can be fatal in a small percentage of cases.

hepatitis D, delta hepatitis

a disease caused by the hepatitis D virus; transmitted via infected blood, contaminated needles, or sexual contact with an infected person; the virus only causes disease in patients who already have HBV.

hepatitis E

a disease caused by the hepatitis E virus; transmitted via food or drink handled by an infected person, or through infected water supplies in areas where fecal matter may get into the water; more common in tropical and subtropical regions of the world than in the United States and Canada.

hepatitis C screening test

see anti-HCV antibody.

hepatocellular carcinoma (HCC)

the most common malignant tumor of the liver; chronic hepatitis B and C are risk factors for this cancer especially in those with cirrhosis; also known as liver cancer, hepatoma, and HCC.


a doctor whose practice is limited to diseases and disorders of the liver.


protective of the liver.


toxic to the liver.


the study of the form of cells and tissues that can only be seen with the microscope; also called microscopic anatomy


see human immunodeficiency virus.


a substance produced in the body that controls and regulates the activity of other cells or organs; most hormones are secreted by specialized glands such as the thyroid gland; they control digestion, metabolism, growth, reproduction, mood and other essential body functions.

human immunodeficiency virus (HIV)

the virus that causes AIDS (acquired immunodeficiency syndrome); HIV infection weakens the body's immune defenses by destroying CD4 lymphocytes (T cells).

humoral immunity

one of the two branches of the immune system that protects the body from infections through the use of antibodies.


a condition caused by excess production of thyroid hormone resulting from an overactive thyroid gland.


deficiency of the thyroid hormone from the thyroid gland.

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see immunoglobulin.

IL-10 (interleukin 10)

an anti-inflammatory and immunosuppressive cytokine; normally produced in the body at sites of injury and inflammation; controls the degree of inflammation.

immune globulin

a concentrated preparation of gamma globulins (antibodies) taken from a large group of human donors that is given by injection for the treatment of specific diseases; used to treat hepatitis A in people already infected with HBV and/or HCV; also known as gamma g.

immune system

a complex group of cells and organs that collectively protect the body from bacterial, parasitic, fungal, and viral infections and from the growth of tumor cells; includes T-helper cells (CD4 cells), T-suppressor cells, natural killer cells, B cells, granulocytes (polymorphonuclear leukocytes), macrophages, dendritic cells, the bone marrow, the thymus gland, the spleen, and the lymph nodes.


the condition of being protected from an infectious disease either by the action of the immune system or immunization (vaccines).


see antigen.


proteins that act as antibodies in the body; produced by plasma cells and B lymphocytes; part of the humoral immune response; antibodies that attach to foreign substances such as bacteria and viruses and assist in destroying them; also known as Ig.


substances or processes that decrease the immune response.


treatment to stimulate or restore the ability of the immune system to fight infection and disease; a treatment that acts by stimulating or working with the immune system.

indirect bilirubin

see bilirubin, unconjugated bilirubin.


a localized tissue reaction to irritation, injury, or infection; usually characterized by swelling, redness, pain, and sometimes loss of function; abnormally intense inflammation can cause tissue damage as in chronic hepatitis C.


the hormone that controls the level of glucose in the blood; allows glucose to move from the blood into cells; produced in the pancreas by specialized cells called beta cells.


any of a group of glycoprotein cytokines that occur naturally in the body; they can have antiviral, and antibacterial actions; synthetic interferons are used to treat a number of diseases; interferons are the basis for current western therapy for chronic hepatitis C.

interferon-based therapy

any therapy that uses interferon as the main component; interferon-based therapy is currently the standard treatment of chronic hepatitis C in western (allopathic) medicine.


a metal found in red blood cells; helps red blood cells carry oxygen to all the cells of the body.

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yellowish discoloration of the skin and whites of the eyes caused by abnormally high amounts of bilirubin in the body.

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weariness, listlessness, or reduced energy.


a state of sluggishness, inactivity, and apathy.

lichen planus

recurrent skin rash characterized by small, flat-topped, many-sided (polygonal) bumps that can grow together into rough, scaly patches on the skin; may occur in the lining (mucous membrane) of the mouth or vagina.


see lactate dehydrogenase.

liver biopsy

the removal and subsequent microscopic examination of small samples of liver tissue; the only reliable method to determine the amount of damage done to the liver by the hepatitis C virus; performed by inserting a long needle through the skin into the liver.

liver cancer

see hepatocellular carcinoma.

liver enzyme

any of the many enzymes present in liver cells including ALT, AST, GGT, LDH, alkaline phosphatase, and others; liver enzymes are monitored in chronic hepatitis C to determine the amount of ongoing damage occurring in the liver.

liver failure

a state in which the liver is unable to adequately perform its many functions; usually the result of end-stage cirrhosis; characterized by clotting abnormalities, protein abnormalities, abnormal electrolytes, and many other signs and symptoms.

liver function test(s)

any of a number of tests used to check for liver function; includes bilirubin, albumin, prothrombin time, total protein, and many others.

living donor liver transplantation

a new procedure involving the transplantation of a portion of a liver from a living donor to replace a failed liver; both livers can grow to normal size.

lymph node

small clusters of immune cells, especially lymphocytes, located throughout the body along the channels of the lymphatic system; found in the underarms, groin, neck, chest, abdomen, and other areas throughout the body; also called lymph glands.

lymph system

see lymphatic system.

lymphatic fluid

the colorless slightly opaque fluid that travels through vessels called lymphatics that connect the lymph nodes in the body; carries immune cells that help fight infection and disease.

lymphatic system (lymph system)

the network of lymph nodes and lymph vessels (lymphatics) in the body; lymph nodes are small, tightly packed collections of lymphocytes that filter, attack, and destroy organisms that cause infection; organs and tissues involved in the lymphatic system include bone marrow, thymus gland, liver, spleen, and collections of lymphatic tissue in the throat and small intestine.

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impaired or inadequate absorption of nutrients from the digestive tract; also known as maldigestion.


see malabsorption.


any of many practices in which the mind is inwardly focused and quieted; the practice is a spiritual practice for many but is also used for stress reduction; meditation is known to lower levels of cortisol (a hormone released in response to stress), and is believed to enhance the immune system.

membranoproliferative glomerulonephritis (MPGN)

an inflammatory condition of the kidneys in which immune deposits in the tiny blood vessels of the kidneys cause damage and impair their filtering capability.


statistical analysis that allows the results of several different studies of the same subject to be combined and analyzed.


the collective biochemical processes that occur in a living organism; involves the balanced process of anabolism (building up or creating substances) and catabolism. (breaking down or using substances); commonly used to refer the breakdown of food and its transformation into energy.


a microscopic organism; includes bacteria, viruses, algae, fungi, protozoa, and some parasites; also known as a microorganism.


a microscopic organism; includes bacteria, viruses, algae, fungi, protozoa, and some parasites.


having only one sexual partner.


the use of a single drug to treat a particular disorder or disease.


a permanent change in a gene or chromosome of an organism creating a new characteristic or trait not previously found; mutations can lead to new resistance to treatment; mutated versions of HCV are known as quasispecies.


pain or ache in muscle(s).

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abbreviation for nonalcoholic fatty liver.


abbreviation for nonalcoholic fatty liver disease.


abbreviation for nonalcoholic steatohepatitis.

NAT Nucleic acid test

detects HCV RNA by amplification of viral genetic sequences.

natural killer cell

a member of the lymphocyte family of white blood cells; part of the cell-mediated immune system; an important immune cell that kills invading microbes and attacks tissues it sees as foreign; also called an NK cell.


death of cells or tissues.


a condition that involves damage to the peripheral nerves (those nerves outside of the brain and spinal cord); many neuropathies affect those nerves most distant from the spinal cord, that is those of the hands and feet; sensation is altered with neuropathy and patients may experience any of several symptoms including numbness, tingling, and pain.


a type of granular white blood cell that attacks microorganisms such as bacteria.

NK cell

see natural killer cell.

non-Hodgkin's lymphoma

a form of cancer of the lymphatic system.


a person who does not respond to therapy at all or a person who initially responds to therapy, then experiences a relapse or has abnormal liver enzyme tests during therapy.


not due to any single known cause, such as a specific pathogen.

nutritional supplement

any product such as a vitamin, mineral or other substance that is taken to augment the amount of nutrients in the diet; used to improve overall health and/or to help correct specific health problems.

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Occupational Safety and Health Administration, U.S. Department of Labor.


thinning of the bones with reduction in bone mass due to depletion of calcium and bone protein; a condition that predisposes to bone fractures that are often slow to heal and/or heal poorly; more common in older adults, particularly postmenopausal women and people taking steroidal drugs.

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partial thromboplastin time (PTT)

a test to see how quickly blood is able to form a clot.


an agent that causes disease, particularly a living microorganism such as a virus or bacterium.


the development of a disease or illness.


relating to or caused by disease.


see HCV polymerase chain reaction.


see porphyria cutanea tarda.

pedal edema

swelling of the feet caused by an excess accumulation of fluid in the body.


see pegylated interferon.

pegylated interferon

a form of interferon in which polyethylene glycol molecules have been bound to the interferon molecule; pegylated interferon has a slower rate of breakdown and clearance from the body than standard interferon.


tiny, flat, round, purplish-red spots on the skin caused by bleeding between the layers of the skin or in the mucosal membranes.


the study of drugs; includes study of drug sources and their properties; also the study of the body's metabolism of and reaction to drugs.


see physiological.


normal; not pathologic; characteristic of the normal functioning or state of the body, or a tissue or organ.

pituitary (gland)

the main endocrine gland that controls endocrine functions in the body; called the master gland because it produces hormones that control other glands and many body functions.


an inactive substance, or dummy medication, or sugar pill; widely used in clinical trials to test if an observed effect is truly due to the experimental drug; for a drug to be considered effective, it must show significantly better results than that produced by the placebo.


an irregular, disc-shaped element of the blood that assists in blood clotting; during normal blood clotting, platelets group together (aggregate); platelets are fragments of larger cells called megakaryocytes; liver disease can cause a shortage of platelets.


a compound created by joining smaller molecules called monomers.


any enzyme that catalyzes polymerization, the successive joining together of smaller monomers to make a polymer.

porphyria cutanea tarda (PCT)

an inherited disorder of porphyrins metabolism; the liver uses porphyrins to make hemoglobin, the iron-containing portion of the red blood cells; PCT can be acquired with certain types of chemical poisoning.

portal hypertension

increased blood pressure in the portal vein that brings blood into the liver; usually occurs because scarring in the liver resists the free flow of blood into the liver; the increased pressure in the portal vein also causes increased pressure in the veins of the abdomen, intestines, stomach, and esophagus; portal hypertension causes many of the complications associated with liver cirrhosis.

portal vein

the large vein that carries blood from the intestines to the liver for processing before returning it to circulation via the hepatic veins.


a charged particle called an electrolyte; one of the four major electrolytes in the body; blood levels may be abnormal in cirrhosis and a variety of other diseases.


the probable outcome or course of a disease; a person's chance of recovery from a disease or injury.


see proteinase.

protease inhibitor

any of a class of anti-HIV (or HCV) drugs designed to inhibit the HIV (or HCV) protease enzyme; protease inhibitors prevent the replication of viruses.


a large molecule composed of one or more chains of amino acids (peptides); proteins are required for the structure, function, and regulation of the body's cells, tissues, and organs; the liver is responsible for making many of the body's proteins.

prothrombin time (PT)

the time it takes for blood to form a clot; monitored in liver disease to assess liver function; many of the proteins needed for clotting are produced in the liver.


a detailed plan for medical treatment or an experiment.


intense itching of the skin.


a reddish, scaly rash often located on the elbows, knees, scalp, and around or in the ears, navel, genitals or buttocks; caused by the body making too many skin cells; some cases are believed to be autoimmune conditions.


having aspects of social and psychological behavior.


see prothrombin time.


see partial thromboplastin time.

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species of viruses that are very similar but have differences; quasispecies are the result of a virus mutation; mutation can cause several quasispecies to exist in the same person.

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RA factor

a specific antibody present in the blood of 60-80% of people with rheumatoid arthritis.

randomized clinical trial

see clinical trial.


see red blood cell.


a combination of interferon alfa-2b and ribavirin used to treat hepatitis C infection; ribavirin is taken by mouth and interferon alfa-2b is administered subcutaneously (beneath the skin).

recombinant immunoblot assay (RIBA)

a sensitive testing method used to detect the presence of anti-HCV antibodies in the blood; most often used to confirm a positive result on an EIA (enzyme immunoassay) screening test for anti-HCV antibodies.

red blood cell

cells that carry oxygen from the air we breathe to all the organs and tissues of the body; supply may be decreased in people with liver disease.


the return of signs and symptoms of a disease following a period of remission (absence of the disease; in hepatitis C, a relapse is the reappearance of the virus after an period of it being undetectable; less frequently used to mean a spike in the liver enzymes after a period of being normal.


someone who has experienced a relapse (see relapse.


the resolution of the signs and symptoms of a disease; can be temporary or permanent.


relating to the kidneys.


process of duplicating or reproducing; viral reproduction is called replication.

replication rate

the rate at which a virus or other microbe is able to reproduce itself.


in chronic viral illnesses (such as HIV) a place in the body where the virus exists but is not detectable by usual medical means; some researchers believe there is a possibility there is one or more reservoirs of HCV in the body, at least in some people with the infection.


see vitamin A.


an RNA virus; a virus with an RNA genome instead of a DNA genome.

rheumatoid arthritis

an autoimmune disease that causes chronic inflammation of the joints, the tissue around the joints, and other organs in the body.

rheumatoid factor

an autoantibody; see autoantibodies for additional details.


see recombinant immunoblot assay.


a nucleoside analogue drug; it has no activity against HCV when used alone, but is effective in some people when used in combination with interferon; ribavirin is believed to act against HCV not as antiviral but as an immune enhancer.


see ribonucleic acid.

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see blood serum.


see aspartate aminotransferas.


see alanine aminotransferase.

S/Co ratio

Signal to cut-off ratio, calculated by dividing the OD value of the sample being tested by the OD value of the assay cut-off for that run.


a charged particle called an electrolyte; one of the four major electrolytes in the body; blood levels may be abnormal in cirrhosis and a variety of other diseases.


see ultrasonography.

spontaneous clearing

in hepatitis C, the ability to rid the body of virus without treatment; this occurs in 15-45% of people infected with HCV.


in hepatitis C, the degree of fibrosis present on liver biopsy; the higher the stage, the more fibrosis present.


the presence of fat in the liver cells with inflammation.


accumulation of fat in the liver that can cause inflammation and lead to fibrosis and/or cirrhosis.


Sexually transmitted disease.

Supplemental test

more specific test (e.g., RIBA or NAT) used to verify a positive anti-HCV screening test result.

sustained responder

in hepatitis C, a person who has no detectable virus in his or her blood and whose liver enzyme tests continue to be normal six months after completing therapy.

sustained response

see sustained responder.


any subjective change (something experienced by the patient) that may indicate a disease process such as fatigue, pain, thirst, etc..

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T cell

a type of white blood cell that is a crucial part of the immune system; they activate the rest of the immune system and directly attack invading organisms; also known as T lymphocyte.

T suppressor cell

a member of the T lymphocyte family of white blood cells that are part of the body's immune system; these cells act to blunt the immune response.

thymus gland

the organ in which T lymphocytes (such as CD4 and CD8 T cells) mature; part of the immune system.

thyroid gland

the organ that produces thyroid hormones that control the metabolic rate of every cell in the body.


inflammation of the thyroid gland; can cause the release of excess of thyroid hormones into the blood stream.


ringing in the ears; can be caused by certain medications (such as aspirin and other anti-inflammatory drugs), aging, trauma, and other disorders.

total bilirubin

see bilirubin, total bilirubin.

total protein (TP)

a measurement of all proteins in the blood; used to determine how well the liver is performing its job of making proteins.


poisonous; capable of causing injury or harm, especially by chemical means.


the quality of being toxic.


a poisonous substance, particularly a protein produced by living cells or organisms; certain toxins are capable of inducing the immune system to produce neutralizing antibodies called antitoxins.


see total protein.


a form of fat that exists in many foods and in the body; triglycerides in blood come from fats in foods and can also made in the body.


an abnormal mass of tissue that can be either benign (noncancerous) or malignant (cancerous).

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diagnostic imaging technique that uses sound waves to construct a picture (sonograph) of an internal organ or body structure; also known as sonography.


high-frequency sound waves; an ultrasound test (sonography) bounces sound waves off internal organs of the body to construct images of the target organ; liver ultrasound is used to screen for liver cancer.

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the introduction of vaccine into the body for the purpose of inducing immunity to a specific disease or group of diseases.


a suspension of weakened or killed microorganisms, or other substances that are introduced into the body to induce an immune reaction; the immune reaction is intended to protect the recipient from getting the illness associated with a specific microorganism; newer vaccines are being developed to alter the course of infectious diseases.


see varix.

varix (pl. varices)

an abnormally dilated or swollen vein; portal hypertension can cause esophageal varices that can rupture and cause vomiting of large amounts of blood; bleeding esophageal varices are a medical emergency.


relating to the blood vessels of the body.


a general term for a group of diseases that feature inflammation of the blood vessels.


the sensation of dizziness or spinning.

viral clearance

elimination of a virus or reducing it to the point that it cannot be detected in the blood.

viral load

the amount of virus present in the blood.


a scientist who specializes in the study of viruses.


the branch of microbiology that is concerned with viruses and viral diseases.

vitamin A

a fat-soluble vitamin; may be deficient with severe liver disease leading to night blindness, dry skin, and brittle hair and nails.

vitamin D

a fat-soluble vitamin; may be deficient with severe liver disease leading to softening of the bones and bone pain.

vitamin E

a fat-soluble vitamin; may be deficient with severe liver disease leading to a shortage of red blood cells and muscle loss.

vitamin K

a fat-soluble vitamin; may be deficient with severe liver disease leading to easy bruising and bleeding problems.


Veterans Affairs.

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see white blood cells.

white blood cells

part of the body's immune system; different kinds of white blood cells include neutrophils, lymphocytes, and macrophages; a change in white blood cell count may indicate a change in hepatitis C disease status.

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Source: Hepatitis C Choices: Diverse Viewpoints and Choices for Your Hepatitis C Journey; Caring Ambassadors Program, Inc.