Glossary of Medical Terms – I | Hepatitis Central

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Glossary of Medical Terms – I

Unintended and unwanted result of treatment
Inflammatory Bowel Disease
An ingredient in certain over-the-counter (nonprescription) medications that reduce swelling, pain, and fever
Ideal Body Weight
International Classification of Disease
Iceland Moss
Cetraria Islandica–This herb is considered demulcent, tonic, and nutritive when deprived of its bitter principle. Recommended in chronic pulmonary troubles, catarrh, digestive disturbances, dysentery, and advanced tuberculosis
Intracellular Fluid
Icing Liver
Perihepatitis chronica hyperplastica
Jaundice, Jaundiced
Intraductal Secretion Test
-Injection Drug Use
Intraepithelial Leukocyte
Abbreviation for Interferon
Immune Globulin

ont>, etc–Immunoglobulin

IgM – IgG
Immunoglobulin type M, type G. Vulgarisation name: antibodies
Intermediate Low Density Lipoprotein
Ileoanal Anastomosis
Surgical procedure where the entire colon together with the diseased inner lining of the rectum is removed, leaving the outer muscle coats of the rectum intact. The end of the ileum is tunneled through the remaining rectum and joined to the anus. Because the rectal muscles and anal valve are left intact, stools can be passed normally
Inflammation of the ileum and colon
Surgical creation of an opening from the ileum to the surface of the body
Lowest part or end of the small intestine
Abbreviation for intramuscular (pertaining to injections)
Immune Adherence Reaction
Method for the detection of very small quantities of antibody in which the antigen-antibody-complement complex adheres to indicator cells, usually primate erythrocytes or nonprimate blood platelets. The reaction is dependent on the number of bound C3 molecules on the C3b receptor sites of the indicator cell
Immune Complex Diseases
Diseases caused by the formation of immune complexes in tissues or by the deposition of circulating immune complexes in tissues resulting in acute or chronic inflammation. Deposition of circulating immune complexes is generally associated with glomerulonephritis, vasculitis, synovitis, endocarditis, neuritis, and dermatitis. Locally formed complexes are involved in the pathogenesis of some autoimmune diseases. Circulating complexes may result from administration of heterologous antigens (as in serum sickness) or from the immune response to microbial antigens or tumor antigens
Immune Globulin
Hyperimmune globulin is prepared from the plasma of individuals who have high titers of antibody against a specific organism or antigen. It is derived from artificially hyperimmunized donors or from persons convalescing from natural infections. Specific immune globulins available include those for hepatitis B, rabies, tetanus, and varicella-zoster
Immune Response
The body’s to specific invading antigens. The body’s protective reaction to an invasion by any disease-causing organisms or “foreign” substances
Immune Sera
Serum that contains antibody or antibodies; it may be obtained from an animal that has been immunized either by injection of antigen into the body or by infection with microorganisms containing the antigen. Antisera may be monovalent (specific for one antigen) or polyvalent (specific for more than one antigen)
Immune System
System which the body defends itself against invasion by viruses, fungi, bacteria, malignant cells and parasites. Cellular and molecular components having the primary function of distinguishing self from non-self and defense against foreign organisms or substances. The primary cellular components are lymphocytes and macrophages, and the primary molecular components are antibodies and lymphokines
Immune Tolerance
Specific failure of a normally responsive individual to make an immune response to a known antigen. It results from previous contact with the antigen by an immunologically immature individual (fetus or neonate) or by an adult exposed to extreme high-dose or low-dose antigen, or by exposure to radiation, antimetabolites, antilymphocytic serum, etc
Physiologic state which makes the body able to recognize materials as foreign to itself and neutralize, eliminate, or metabolize them with or without injury to its own tissues
Immunity, Mucosal
Nonsusceptibility to the pathogenic effects of foreign microorganisms or antigenic substances as a result of antibody secretions of the mucous membranes. Mucosal epithelia in the gastrointestinal, respiratory, and reproductive tracts produce a form of IgA (IGA, Secretory) that serves to protect these ports of entry into the body
Immunoblastic Lymphadenopathy
A disease characterized by fever, itching, rash, sweating spells, weight loss, proliferation of small blood vessels and of immunoblasts, generalized lymphadenopathy, and enlargement of the liver and spleen
Immunocompromised Host
Human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation
The ability of a vaccine to stimulate the immune system, as measured by the proportion of individuals who produce specific antibody or T cells, or the amount of antibody produced
Protein molecule functioning as a specific antibody, it  will bring about the humoral phase of immunity. Five possible types of Immunoglobulin include, IgA, IgG, IgM, IgE, IgD
Branch of medicine that focuses on the immune system, allergies and induced sensitivity. Scientific study of the bodies response to antigens
Capable of altering immunity
Damage to the host caused by its own immune response against a pathogen
Prevention or diminution of the immune response, as by irradiation or by administration of antimetabolites, antilymphocyte serum, or specific antibody; also known as Immunodepression. A reduction in the capacity of the immune system. Caused by infection (eg HIV), drug treatment, pregnancy and malnutrition among others. Immunosuppressed individuals are commonly referred to as immunocompromised
Immunosuppressive Agents
Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of suppressor T-cell populations or by inhibiting the activation of helper cells. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of interleukins and other cytokines are emerging
Immunotherapy, Active
Active immunization where vaccine is administered for therapeutic or preventive purposes. This can include administration of immunopotentiating agents such as BCG vaccine and Corynebacterium parvum as well as biological response modifiers such as interferons, interleukins, and colony stimulating factors in order to directly stimulate the immune system
Immunosuppressive drug used with other immunosuppressive drugs to help prevent the rejection of a transplanted organ. Also known by its chemical name, azathioprine
Hardened mass of stool difficult to pass from the body
The number of new infections that occurs in a given period of time. The frequency of occurrence of a condition, disease, symptom, or injury
Cut, or a wound produced by cutting with a sharp instrument
Inclusion Bodies
Strange and unusual structures found inside a host cell during virus replication
Incubation Period
The time that elapses between infection and the appearance of symptoms of a disease
Investigational New Drug
Term used to indicate any disruption in the digestive process. Symptoms commonly include heartburn, nausea, bloating, and gas. Physicians often call it Dyspepsia
Indirect Life Cycle
A life cycle which requires one or more intermediate hosts before the definitive host species is reinfected
Indirect Transmission
Transmission of a parasite through an indirect life cycle
Indocyanine Green
A green dye used especially in testing liver blood flow and cardiac output
Infantile Liver
Biliary Cirrhosis of children
Permanent damage to tissue or organ from interruption of its blood supply
A host who has an infection
Disease that results from the presence of harmful microorganisms in the body. The presence of a parasite within a host where it may or may not cause disease
Infectious Diarrhea
Also called Traveler’s Diarrhea. Diarrheal illness caused by an infectious agent: bacterial, protozoan or viral
Infectious Disease Subspecialist
These subspecialists deal with infectious disease of all types and in all organs. Conditions requiring selective use of antibiotics call for this special skill. AIDs patients and patients with fevers which have not been explained are often diagnosed and treated by these subspecialists. Infectious disease subspecialists are experts in preventive medicine and conditions associated with travel
Infectious Period
The time period during which infecteds are able to transmit an infection to any susceptible host or vector they contact. The infectious period may not necessarily be associated with symptoms of the disease
Introduce medication, typically local anesthetic, into an area of tissue
Localized protective response elicited by injury or destruction of tissues. Symptoms: pain, heat, swelling and redness, loss of function, involves a complex series of events, including dilatation of arterioles, capillaries, and venules, with increased permeability and blood flow; exudation of fluids, including plasma proteins; and leukocytic migration into the inflammatory focus. Condition in which the body is trying to respond to localized injury or destruction of tissues
Inflammatory Bowel Disease
Name for a group of disorders in which various parts of the intestinal tract are inflamed. Most common disorders are Crohn’s Disease and Ulcerative Colitis
Inflammatory Debris
Damaged tissue and tissue-products resulting from inflammation (usually infection) rather than other pathological processes
Influenza A
Contagious infectious disease attributed to a filterable virus and causing fheadache, fever, pain in the limbs and back. Inflammation of the respiratory tract
Information Therapy
Extraction of the active properties of a substance by soaking or steeping it, usually in water
To consume orally
Act of drawing air into the lungs. Method of treating illness by inhaling medicinals rather than injecting or drinking them
Initial Treatment
The first time you are treated for a specific disease or ailment. Treatment after this is called Subsequent Treatment
Introduction of nutritional or medicinal materials through a needle into the body
Injection Site
Particular place on the body where the injection is made
Inlet Sinusoid
The entry channel from a portal venule into the sinusoidal network
Distribution or supply of nerves to a part
The amount of parasite to which an individual host is exposed at transmission
Inorganic Phosphorus
Hyperphosphatemia may occur in myeloma, Paget’s disease of bone, osseous metastases, Addison’s disease, leukemia, sarcoidosis, milk-alkali syndrome, vitamin D excess, healing fractures, renal failure, hypoparathyroidism, diabetic ketoacidosis, acromegaly, and malignant hyperpyrexia. Drugs causing serum phosphorous elevation include androgens, furosemide, growth hormone, hydrochlorthiazide, oral contraceptives, parathormone, and phosphates. Hypophosphatemia can be seen in a variety of biochemical derangements, incl. acute alcohol intoxication, sepsis, hypokalemia, malabsorption syndromes, hyperinsulinism, hyperparathyroidism, and as result of drugs, e.g., acetazolamide, aluminum-containing antacids, anesthetic agents, anticonvulsants, and estrogens (incl. oral contraceptives). Citrates, mannitol, oxalate, tartrate, and phenothiazines may produce spuriously low phosphorous by interference with the assay
Usually considered part of the vitamin B complex. Thought that along with choline, inositol is necessary for the formation of lecithin within the body. Involved in calcium mobilization. Inositol aids in the breakdown of fats, helps reduce blood cholesterol, and even helps prevent thinning hair. A deficiency of Inositol may result in high blood cholesterol, constipation, eczema, and/or hair loss
In Situ Hybridization
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes
An adjective that describes a substance that is incapable of being dissolved in a liquid
Protein pancreatic hormone that is essential especially for the metabolism of carbohydrates and is used in the treatment and control of diabetes mellitus. Hormone produced in the islets of Langerhans in the pancreas, concerned with the regulation of carbohydrate metabolism by controlling glucose levels in the blood. Extracted from the pancreas of pork or  beef for use in treatment of diabetes
Insulin-Like Growth Factor
Either of two somatomedins that are produced in the liver and in fibroblasts, the adrenal glands, and the gonads, that are produced esp. in response to growth hormone, and that mediate growth hormone activity
An enzyme found especially in liver that inactivates insulin
Prefix meaning between or among
Between ribs
Between ducts
A naturally occurring chemical (protein) in the body that helps the immune system to clear viruses such as hepatitis B or C. Our livers produce at least 26 types of natural interferon. Produced by body cells in response to invasion by viruses and other intracellular parasites; it interferes with the synthesis of new virus and is effective against certain protozoal parasitic infections. Any of a group of heat-stable soluble basic antiviral glycoproteins of low molecular weight that are produced usually by cells exposed to the action of a virus, sometimes to the action of another intracellular parasite (such as bacterium), or experimentally to the action of some chemicals, and that include some used medically as antiviral or antineoplastic agents
One of the type I interferons (Interferon Type I) produced by peripheral blood leukocytes or lymphoblastoid cells when exposed to live or inactivated virus, double-stranded RNA, or bacterial products. It is the major interferon produced by virus-induced leukocyte cultures and, in addition to its pronounced antiviral activity, causes activation of NK cells. It is used experimentally in the treatment of hairy-cell leukemia
Interferon Alfa-2a
Interferon A (human leukocyte protein moiety reduced). A type I interferon consisting of 165 amino acid residues with lysine in position 23. This protein is produced by recombinant DNA technology and resembles interferon secreted by leukocytes. It is used extensively as an antiviral or antineoplastic agent
Interferon Alfa-2b
Interferon alpha 2b (human leukocyte clone Hif-SN 206 protein moiety reduced). Type I interferon consisting of 165 amino acid residues with arginine in position 23. This protein is produced by recombinant DNA technology and resembles interferon secreted by leukocytes. Used extensively as an antiviral or antineoplastic agent
Interferon Alfa, Recombinant
A type I interferon with antiviral and antineoplastic activity produced by recombinant DNA technology. Can be a mixture of the kind of interferon secreted by leukocytes or lymphoblasts
Interferon, Beta
The major interferon produced by double-stranded RNA-induced fibroblast cultures; the primary producer cells are fibroblasts, epithelial cells, and macrophages, and the major activity is antiviral activity. Called also epithelial, fibroblast, or fibroepithelial. One of the type I interferons produced by fibroblasts in response to stimulation by live or inactivated virus or by double-stranded RNA. It is a cytokine with antiviral, antiproliferative, and immunomodulating activity
Interferon-Gamma, Recombinant
A type II interferon produced by recombinant DNA technology. It is similar to the interferon secreted by lymphocytes and has antiviral and antineoplastic activity
Interferon Inducers
Agents that promote the production and release of interferons. They include mitogens, lipopolysaccharides, and the synthetic polymers Poly A-U and Poly I-C. Viruses, bacteria, and protozoa have been also known to induce interferons
Any of a family of glycoproteins that exert virus-nonspecific but host-specific antiviral activity by inducing the transcription of cellular genes coding for antiviral proteins that selectively inhibit the synthesis of viral RNA and proteins. Interferons also have immunoregulatory functions (inhibition of B cell activation and antibody production enhancement of T cell activity, and enhancement of NK cell cytotoxic activity) and can inhibit the growth of nonviral intracellular parasites. Production of interferon can be stimulated by viral infection, especially by the presence of double-stranded RNA, by intracellular parasites (chlamidiae, rickettsiae), by protozoa (Toxoplasma) and by bacteria (streptococci, staphylococci) and bacterial products (endotoxins). Interferons have been divided into three distinct types associated with specific producer cells and functions, but all animal cells are able to produce interferons, and certain producer cells (leukocytes and fibroblasts) produce more than one type (both interferon- and interferon). Abbreviated IFN
Interferon Type I
Interferon secreted by leukocytes, fibroblasts, or lymphoblasts in response to viruses or interferon inducers other than mitogens, antigens, or allo-antigens. They include alpha- and beta-interferons (Interferon-Alpha and Interferon-Beta)
Interferon Type II
Major interferon produced by immunologically stimulated (by mitogens or antigens) lymphocyte cultures; the primary producer cells are T lymphocytes, and the major activity is immunoregulation. IFN- has been implicated in aberrant expression of class II histocompatibility antigens by tissue cells (such as thyroid cells) that do not normally express them, leading to autoimmune disease
Macrophage-produced interleukin that induces the production of interleukin-2 by T cells that have been stimulated by antigen or mitogen; at least two types exist, designated and IL-1 or a similar protein is also produced by epithelial cells and stimulates fibroblast proliferation and release of proteolytic enzymes (e.g., collagenase) and prostaglandins in inflammatory processes. IL-1 also appears to be identical to endogenous pyrogen. Formerly called lymphocyte-activating factor (LAF)
Interleukin produced by T cells in response to antigenic or mitogenic stimulation and the signal carried by interleukin-1. It stimulates the proliferation of T cells bearing specific receptors for IL-2, which are only expressed by antigenically stimulated T cells. IL-2 also seems to induce production of interferon. It is used as an anticancer drug in the treatment of a wide variety of solid malignant tumors. Also called T-cell growth factor (TCGF)
Lymphokine produced by antigen- or mitogen-activated T lymphocytes, which stimulates proliferation of hematopoietic as well as lymphoid stem cells; a colony-stimulating factor for all bone marrow progenitor cells. IL-3 supports the growth and differentiation of early hematopoietic and lymphoid stem cells as well as that of more mature hematopoietic cells, including granulocytes, macrophages, and mast cells
Soluble factor produced by activated T-lymphocytes that causes proliferation and differentiation of B-cells. Interleukin-4 induces the expression of class II major histocompatibility complex and Fc receptors on B-cells. It also acts on T-lymphocytes, mast cell lines, and several other hematopoietic lineage cells including granulocyte, megakaryocyte, and erythroid precursors, as well as macrophages
Factor promoting eosinophil differentiation and activation in hematopoiesis. It also triggers activated B-cells for a terminal differentiation into Ig-secreting cells
Factor that stimulates the growth and differentiation of human B-cells and is also a growth factor for hybridomas and plasmacytomas. It is produced by many different cells including T-cells, monocytes, and fibroblasts
Hematopoietic growth factor that promotes growth of B-cell precursors and also is co-mitogenic with Interleukin-2 for mature T-cell activation. It is produced by bone marrow stromal cells
Cytokine that activates neutrophils and attracts neutrophils and T-lymphocytes. It is released by several cell types including macrophages, monocytes, T-lymphocytes, endothelial cells, fibroblasts and keratinocytes by an inflammatory stimulus. IL-8 is a member of the beta-thromboglobulin superfamily. Structurally related to platelet factor 4
Factor that is thought to be a regulator of hematopoiesis. It has been shown to enhance the growth of human mast cells and megakaryoblastic leukemic cells as well as murine helper t-cell clones. IL-9 is a glycoprotein with a molecular weight of 32-39 that is derived from T-cells, and maps to human chromosome 5
Factor that is a coregulator of mast cell growth. It is produced by T-cells and B-cells and shows extensive homology with the Epstein-Barr virus BCRFI gene
Lymphohematopoietic cytokine that has the ability to modulate antigen-specific antibody responses, potentiate megakaryocytes, and regulate bone marrow adipogenesis
Heterodimeric cytokine that stimulates the production of interferon gamma from T-cells and natural killer cells and also induces differentiation of TH1 cells. Consequently, it is the initiator of cell-mediated immunity
T-lymphocyte-derived cytokine that produces proliferation, immunoglobulin isotype switching, and immunoglobulin production by immature B-lymphocytes. It appears to play a role in regulating inflammatory and immune responses
Cytokine that induces B-cell proliferation, inhibits immunoglobulin secretion, and selectively expands certain B-cell subpopulations
Cytokine that stimulates the proliferation of T-lymphocytes and shares biological activities with IL-2. IL-15 also can induce B-lymphocyte proliferation and differentiation
Cytokine produced by activated T-lymphocytes that stimulates the migration of CD4-positive lymphocytes and monocytes. It has been reported to suppress HIV replication
Interleukin Receptors
Cell surface proteins that bind interleukins and trigger intracellular changes influencing the behavior of cells
Generic term for a group of protein factors produced by macrophages and T cells in response to antigenic or mitogenic stimulation and affecting primarily T cells
Internal Medicine
Branch of medicine dealing especially with the diagnosis and medical treatment of disorders and diseases of the internal structures of the human body
International Unit–IU
Quantity of a biologically active substance required to produce a specific response. This unit is often used to express a dosage amount
Intestinal Flora
Name for the bacteria, fungi and yeasts, that normally grow in the intestinal tract
Intestinal Mucosa
Intestinal lining. Surface lining of the intestines in which the process of absorption occurs
Situated within but not restricted to or characteristic of a particular organ or tissue, Affecting the interstitial tissues of an organ or part, Occuring in the part of a fallopian tube in the wall of the uterus
Prefix meaning within, into or during
Situated or occurring within or originating in the liver
Injected into a vein. Also called IV
Intravenous Drugs
Drugs that are injected by a needle directly into a vein
Intravenous Feeding
Procedure in which necessary fluids, nutrients and salts, are supplied to the body by way of the veins
Insertion of an endotracheal tube to help an unconscious patient breathe
Investigational Drug
New drug that is undergoing clinical trials to try and prove its safety and effectiveness
Turning inward, inside out, upside down, or other reversal of normal relation of a part
In Vitro
Latin term meaning “in glass”  or “in body”. The term is applied to biological processes studied experimentally in isolation from the organism
In Vivo
From the Latin meaning “in living” The term is applied the study of processes in the living organism
Essential mineral that is an integral part of the thyroid hormones, thyroxin and triodothyronine which have important metabolic roles and govern basal metabolism. Iodine aids in the development and functioning of the thyroid gland, regulates the body’s production of energy, and helps burn excess fat by stimulating the rate of metabolism. The best known iodine deficiency symptom is goiter. Other iodine deficiency problems are reduced vitality, hypothyrodism, inability to think clearly, low resistance to infection, loss of control of the muscles of the mouth resulting in mouth contortion and drooling, defective teeth, tendency to obesity and cretinism which is a congenital abnormal condition marked by physical stunting and mental deficiency
Atom or group of atoms that has acquired an electric charge through the gain or loss of an electron or electrons
Iintermittent Positive Pressure Breathing
An oleoresin prepared from the common blue flag for use as a purgative and liver stimulant
Irish Moss
Also known as Carrageen and pearl moss. Used effectively as a demulcent and mucilaginous. Irish moss is considered an excellent remedy for bronchitis, coughs, tuberculosis, and intestinal problems. In its raw form, it is used as a bulk laxative, which coats and soothes the entire gastrointestinal tract. In various forms, it relieves peptic and duodenal ulcers in humans without having any adverse effects on the colon
Essential mineral. Iron’s major function is to combine with protein and copper in making hemoglobin. Prevents anemia: as a constituent of hemoglobin, transports oxygen throughout the body. Virtually all of the oxygen used by cells in the life process are brought to the cells by the hemoglobin of red blood cells. Iron is a small but most vital, component of the hemoglobin in 20,000 billion red blood cells, of which 115 million are formed every minute. Serum iron may be increased in hemolytic, megaloblastic, and aplastic anemias, and in hemochromatosis, acute leukemia, lead poisoning, pyridoxine deficiency, thalassemia, excessive iron therapy, and after repeated transfusions. Drugs causing increased serum iron include chloramphenicol, cisplatin, estrogens (including oral contraceptives), ethanol, iron dextran, and methotrexate. Iron can be decreased in iron deficiency anemia, acute and chronic infections, carcinoma, nephrotic syndrome, hypothyroidism, in protein- calorie malnutrition, and after surgery. The iron assay is one of the less reliable tests on screening panels, so any abnormalities should be followed with other inquiry concerning iron metabolism (history of blood loss, alcohol consumption, lab tests for TIBC, ferritin, etc) before undertaking therapeutic interventions. A deficiency of iron may result in general weakness, paleness of skin, constipation, and/or anemia
Iron Liver
The condition of the liver in hepatic siderosis
Wash out a wound or operative field with a cleansing fluid
Washing out of a wounded surface or cavity with a stream of fluid
Irritable Bowel Syndrome
Also called IBS, Mucous Colitis, Spastic Colon. Common functional disorder characterized by  abdominal pain, gas, diarrhea or constipation or alternately by both
Substance that produces irritation or inflammation of the skin or internal tissue
Immune System
When the heart is starving for oxygen
Islets of Langerhans
Irregular microscopic structures, varying from a few to hundreds of cells, scattered throughout the pancreas and comprising its endocrine portion. There are three cell types: alpha, secreting glucagon; beta, secreting insulin; and delta, secreting somatostatin
Antigens that exist in alternative (allelic) forms in a species, and thus induce an immature response when one form is transferred (as by blood transfusion or tissue graft) to members of the species who lack it. Typical isoantigens are the blood group antigens
Essential amino acid. Essential for proper growth in infants and for nitrogen balance in adults
International Units
IV Catheter
Small needle with a hollow tube inserted into a vein and used to give medicines or fluids
Intravenous Drug Abuse
Intravenous Drug User
Intravenous Hyperalimentation
Intravenous gamma globulin
Intravenous Nutrition
IV Push
Injecting medication rapidly into a vein to hit the blood system all at once
Intravenous Urography


© Vikki Shaw