Glossary of Terms
Absolute Neutrophil Count (ANC): The absolute neutrophil count represents the corrected number of neutrophils present in a white blood count. Formula for computing the ANC: # of polys (segs) + bands x WBC = ANC or AGC
Advance Directive (also called a healthcare proxy): An advance directive stipulates a person whom you have chosen to make health decisions for you if you are unable to. It assigns someone you trust (a "proxy" for you) to make choices-in whatever situation arises-that are based on the stated preferences in your living will.
Allogeneic Transplant: The use of a donor's hematopoietic cells to restore bone marrow function and blood cells after receiving the preparative regimen. Hematopoietic cells are obtained from a genetically matched individual. This is usually a brother or sister, but may also be an unrelated volunteer donor.
Alopecia: Temporary loss of hair.
Amphotericin B: An antifungal given intravenously.
Anaphylaxis: Acute allergic reaction with symptoms of shortness of breath, rash, wheezing or hypotension.
Anemia: A low number of red blood cells. One symptom of anemia is fatigue.
Antibiotic: A drug used to fight bacterial infections.
Antibody: A protein produced by the body and in response to a foreign substance, fights the invading organism.
Antiemetic: A drug or combination of drugs used to control nausea or vomiting.
Antigen: A substance that evokes a response from the body's immune system. This results in the production of antibodies or white blood cells.
Antithymocyte Globulin (ATG): An anti T lymphocytic agent, which is used in conditioning protocols, and for treatment of graft-versus-host disease.
Apheresis: The process of taking blood from a donor, separating and collecting blood products (in this case, blood stem cells), and returning the rest back to the donor. A tube or catheter is inserted (usually into a vein in the arm) and blood is removed and run through a machine that removes the stem cells. The rest of the blood is returned to the patient. There is usually no need for hospitalization or anesthesia. Typically, apheresis takes five hours and is usually done twice for each patient. Apheresis is the preferred method for extracting blood stem cells because it is easier, less painful and intrusive for the patient, and less expensive.
Aplasia: A failure to develop or form. In bone marrow, aplasia means the marrow cavity is empty.
Autologous Transplant: The use of one's own hematopoietic cells to rescue you from the low blood counts which occurs after receiving high-dose chemotherapy or radiation that is administered to eradicate cancer.
B Lymphocyte: A cell of the immune system that protects from microorganisms by searching antibodies into the blood.
Bactrim: Antibiotic commonly used to prevent pneumocystis carinii in highly immunosuppressive patients.
Bilirubin: A pigment produced when the liver processes waste products resulting in jaundice.
Blood Cell Separator: A machine, used in apheresis, which distinguishes the small fraction of stem cells in the blood from all other blood cells, so that the stem cells may be collected for transplant.
Bone Marrow: A liquid, similar in appearance to blood, that is found with the soft sponge-like cavities of large bones.
Bone Marrow Biopsy: A procedure used to obtain a sample of bone marrow from the hip bone for microscopic examination.
Bone Marrow Harvest: The collection of immature hematopoietic cells from the hip bones. This procedure is performed in the operating room.
Bone Marrow Aspiration: Aspiration is the process of removing marrow from inside bones so that the blood stems cells in the marrow can be extracted and subsequently transplanted. Aspiration is performed in an operating room and requires that the patient have general anesthesia. During the process, a needle is inserted into several locations in the hip and pelvis, and bone marrow is suctioned out. An aspiration treatment takes about two hours and usually does not need to be repeated.
Central Venous Catheter: An intravenous catheter will be placed in a large vein under the collarbone. The catheter is used to give fluids and medications and to draw blood samples.
Chemoradiotherapy: Refers to treatment modalities utilizing chemotherapy (cytotoxic agents) and radiation, together as pre-transplant conditioning.
Chemotherapy: A drug or combination of drugs used to kill cancer cells.
Colony-Stimulating Factors: Proteins that stimulate the production and growth of certain types of blood cells.
Concomitant Infection: An infection that takes place at the same time as at least on other organism.
Conditioning: Generic term for pre-transplant chemotherapy, radiation, or other treatment designed to destroy malignant cells, and the immune system. Also called preparatory regimen or high-dose therapy.
Cryopreserve: A process by which something (such as cells, sperm or embryos) is frozen to preserve it for later use.
Cyclosporine A: An immunosuppressive drug used for prevention or treatment of graft-versus-host disease.
Cytomegalovirus (CMV): A virus that lies dormant in many persons' bodies and frequently causes infection post-transplant. Patients who have been exposed to CMV and still carry the virus are CMV positive. Important to identify in the allogeneic population.
Differential (Diff): A lab test that reveals the percentages of the different types of white blood cells.
DMSO: A chemical used in autologous marrow for preservation.
Donor: An individual who will donate hematopoietic cells for another individual. Types of donors include siblings (brothers/sisters) and unrelated volunteers. There are varying degrees of genetic matching between a donor and a recipient. The donor and recipient may be fully matched and partially matched. One type of donor is a haploidentical donor. A haploidentical donor is an approximately 50% match.
Dysphagia: Difficulty swallowing.
Eligibility: A series of tests of organ function (heart, liver, kidney and lungs) that determine if you are healthy enough to undergo a transplant. Eligibility also involves assessing how well your disease has responded to treatment.
Engraftment: When bone marrow or stem cells given during transplant begin making new blood cells. This is the process of reestablishing hematopoiesis and the immune system.
Erythrocytes: Red blood cells.
Fungus: An infection responsible for a high mortality rate in the transplant population. Aspergillus fungi is the most common.
Gastrointestinal Tract (GI Tract): The digestive system, including the mouth, esophagus, stomach and intestines.
G-CSF: Granulocyte colony-stimulating factor. A protein that stimulates the growth and maturation of granulocytes.
GM-CSF: Granulocyte-macrophage colony-stimulating factor. A protein that stimulates the growth and maturation of a wide variety of white blood cells.
Graft: A collection of hematopoietic cells that is infused following the preparative regimen. The graft may be autologous (self) or allogeneic (from a donor).
Graft Rejection: The process by which the donated bone marrow infused during a BMT is rejected by the patient's body or doesn't "take."
Graft-versus-Host Disease (GvHD): Graft versus host disease is a complication of allogeneic transplantation. It is an immune reaction of the donor's cells against your body tissues.
Graft-versus-Malignancy: This is an immune response of the donor's cells against the malignancy.
Granulocyte: A class of white blood cells which are responsible for protecting the body against bacterial infections.
Growth Factors: Substances sometimes given to transplant patients to stimulate the production of blood cells, or to stem cell donors to mobilize stem cells into the bloodstream for collection.
Healthcare Proxy: see advance directive.
Hematocrit (HCT): The percentage of red blood cells in the blood.
Normal range for females: 35% - 47%
Normal range for males: 40% - 52%
Hematopoietic Cells: Hematopoietic means of or about the blood, meaning hematopoietic cells are blood cells. Immature hematopoietic cells (often called stem cells) can divide and mature into any type of mature blood cells.
Hemoglobin: A protein in red blood cells that contains iron. Iron binds to oxygen to be carried throughout the body.
Normal range for females: 11.7 – 15.7 g/dl
Normal range for males: 13.5 – 17.7 g/dl
Human Leukocyte Antigen (HLA): The human leukocyte antigen system is a group of markers on the surface of your immune cells. The human leukocyte antigens are genetically determined (inherited). These markers are used to find a donor within your family or from the registry of volunteer donors (such as the NMDP).
Immune System: Specialized cells in the body that protect us from infections caused by microorganisms.
Immunoglobulin: An antibody.
Immunosuppression: The condition in which the patient's immune system is functioning at a lower than normal level.
Infection Control Practices: Measures (activities) designed to reduce the risk of infection.
Informed Consent: Your formal authorization to the hospital to perform transplant procedures. Consent forms may be several pages in length and are written in medical terms, with blunt, detailed descriptions of the risks and side effects associated with BMT, including potential long-term complications.
Interstitial Pneumonitis: An inflammatory process involving the intra-alveolar linings of the lung.
Intravenous: Through a vein.
Karnofsky Score (KS): A measure of the patient's overall physical health and activity.
Laminar Air Flow Unit: A sterile environment where air is first filtered through a "hepafilter" before entering patient's room. The patient's room is separated from anteroom by a clear plastic curtain. All personnel must wear sterile attire to enter the room.
Laminar Airflow (LAF): A type of an air-filtering system used to remove contaminants from the air.
Length of Stay (LOS): The number of days an individual is hospitalized.
Leukocytes: A type of white blood cell (WBC).
Living Will: A living will stipulates your specific instructions regarding life-sustaining therapy. It includes the instructions for your healthcare proxy, if you have designated one.
Lumens (lumen catheter): Lines or tubes attached to a surgically placed temporary catheter, used in place of multiple intravenous lines, to give medication or draw blood.
Lymphocyte: A type of white blood cell that fights infection by producing antibodies and regulating the immune system response.
Macrophage: A type of white blood cell that assists in the body's fight against bacteria and infection by engulfing and destroying invading organisms.
Microorganisms: A microorganism can be a bacteria, virus, protozoa or fungus. Microorganisms cause infections in individuals with low white blood cell count or who are taking immunosuppressants (medications that weaken the immune system).
Mixed Lymphocyte Culture (MLC): Test to determine whether a patient's and donor's white blood cells react, and to estimate the amount of rejection/GvHD.
Mobilization: A process to increase the number of immature hematopoietic cells in the blood. By mobilizing (moving) the immature hematopoietic cells from the bone marrow into the blood, these cells can then be collected from the blood. Mobilization can be accomplished using high dose chemotherapy and/or a hormone that stimulates the bone marrow to make fore hematopoietic cells.
Monoclonal Antibody: A special protein that is designated to target cancer cells for destruction. Rituximab is one type of monoclonal antibody.
Monocyte: A type of white blood cell that fights against bacteria and fungi that invade the body.
Mucositis: Mouth sores from the chemotherapy or radiation. Can range from mild buccal erythema, to severe, life-threatening ulceration. Usually a result of chemoradiotherapy.
Myeloablative: This term means that the preparative regimen will completely eliminate the individuals ability to make blood cells.
NMDP: National Marrow Donor Program
Neutropenia: Low numbers of neutrophils. Neutrophils are an important type of white blood cell that fight bacterial infections.
Normal range: 40% - 60% of the total white blood cell count.
Non-myeloablative: This term means that the preparative regimen will only weaken or depress the individual's ability to make blood cells.
Pancytopenia: A deficiency of all types of blood cells.
Peripheral blood Stem Cells (PBSCs): Stem cells that are circulating in the bloodstream.
Petechiae: Small red or purple spots on the skin that are indicative of a low platelet count.
Platelets: A blood cell that forms a clot to prevent or stop bleeding. Low numbers of platelets increase the risk of bleeding. Normal range: 150 – 400 K/uL
Preparative Regimen: A combination of chemotherapy and/or radiation therapy given prior to transplant. The purpose of the preparative regimen is to eliminate the malignancy. In an allogeneic transplant, the preparative regimen is also given to weaken the immune system so that the donor's cells can grow and function once infused.
Purging: Methods to try to eliminate cancer cells from an autologous graft. Purging can be accomplished by cell sorting or monoclonal antibodies. (DHMC does not purge the stem cell collection.)
Red Blood Cells (RBCs): A blood cell that transports oxygen throughout the body.
Normal range for females: 3.8 – 5.2 MIL/uL
Normal range for males: 4.4 – 5.9 MIL/uL
Reverse Isolation Technique: An isolation technique utilized for patients in non-LAF rooms.
Sepsis: The presence of organisms in the blood.
Stem Cells: Young blood cells, found in the bone marrow, from which all other types of blood cells evolve and differentiate.
Syngeneic Transplant: A transplant from an identical twin.
T Lymphocyte: A cell of the immune system that works to protect your body from foreign tissue and microorganisms. The T lymphocyte is responsible for graft versus host disease and for the graft versus malignancy effect of allogeneic transplantation.
T-Cell Depletion: Removal of the T cells from the bone marrow.
Thrombocyte: See platelet.
Thrombocytopenia: An abnormally low platelet count. A low platelet count increases the risk of bleeding.
Total Body Irradiation (TBI): Radiation therapy given to the entire body.
Transfusions: Administering red blood cells to minimize the symptoms of anemia or platelets to reduce the risk of bleeding.
Urokinase: An intravenous thrombolytic agent that used to restore patency to central lines which have developed fibrin sheaths or clots.
White Blood Cells (WBCs): Defend the body against infection. Types of WBCs include neutrophils, eosinophils, basophils, macrophages, T and B lymphocytes. Each of these cells has a unique role to play in protecting you from infection. Normal range: 4 – 11 K/uL
Xerostomia: Dryness of the mouth caused by malfunctioning salivary glands due to the preparative regimen.