Aplastic Anemia Resources

The Aplastic Anemia & MDS International Foundation
The Aplastic Anemia & MDS International Foundation is the oldest and largest patient advocate and support organization for bone marrow diseases, providing life-saving hope, knowledge, and support to hundreds of thousands of patients and their families around the world.

Glossary of Anemia-Related Medical Terms

  • aplastic anemia: Bone marrow failure where for unknown reasons, the production of blood cells slows or stops.
  • antibody: This is a molecule produced by lymph tissue in response to the presence of an antigen. Antibodies neutralize the effect of the antigen.
  • antigen: Foreign substance that is not usually part of the body's makeup and that stimulates antibody production. The antibody reacts specifically with a particular antigen to destroy or weaken it.
  • bacteria: An organism that can cause infection.
  • bone marrow: Soft tissue within the bones where blood cells are manufactured.
  • bone marrow aspiration: A test in which a sample of bone marrow cells is removed with a needle and examined under a microscope.
  • bone marrow biopsy: A procedure in which a small piece of bone marrow tissue is extracted with a needle. The sample is processed by softening the bone and examining thin slices of the softened bone under a microscope.
  • bone marrow transplant: A procedure in which bone marrow filled with disease is destroyed by radiation or chemotherapy and then replaced with healthy cells from a donor.
  • chromosome: A rodlike structure that appears in the nucleus of a cell during division; contains the genes responsible for heredity.
  • complete blood count: Or CBC is the amount or level of blood cells: white cells, red cells and platelets.
  • cross match: Type and cross is a test in which the blood cells of a donor and a recipient are mixed together to determine if they are compatible.
  • culture: The procedure used to identify the source of infection; specimen of blood, urine, sputum or stool is taken and tested to determine the type of infection and the appropriate antibiotic.
  • differential: The percent of different types of blood cells in the blood.
  • hemoglobin: Or Hg is the iron-containing coloring in the red cells that combine with oxygen from the lungs and carries it to the body's cells.
  • histocompatibility antigens: Or HLA is a group of DNA substances in chromosomes that determine whether certain tissues can be transplanted; also can be used to determine the most compatible platelet donors.
  • human leukocyte antigen: Or HLA is the tissue typing test done on white cells to determine if a donor and recipient are compatible.
  • immunosuppression: Is a decrease in the ability of the body's normal immune response to the invasion of foreign material.
  • lymphocyte: The type of white cell that fights infection by producing antibodies and other defense substances; occurs in 2 forms: B cells that recognize specific antigens and produce antibodies against them, and T cells that are agents of the immune system.
  • neutropenia: Low neutrophil (poly) count.
  • pancytopenia: Low number of blood cells.
  • petechiae: Small red dots on the skin due to bleeding under the skin caused by low platelet counts.
  • peripheral blood: Blood in the bloodstream.
  • platelet: A blood cell that prevents bleeding and bruising.
  • red blood cell: An oxygen carrying cell in the blood which contains the pigment hemoglobin, produced in the bone marrow; erythrocyte.
  • stem cell: A cell from which platelets, red blood cells and white blood cells grow in the one marrow.
  • white blood cells: These are blood cells which fight infection.

Aplastic Anemia & MDS International Foundation, Inc

Patients, families and health care professionals can benefit from these FREE services by calling 800.747.2820 or email at help@aamds.org.

  • Emotional Support provided by toll-free hotline and email.
  • Educational materials explain the disease, treatment options, research updates, clinical trials, patients rights, steps in making treatment decisions, and emotional management.
  • Patient Information Department personally answers questions from patients and family members by a team of medical experts.
  • Clinical Trial Listings includes doctor's name, phone number, hospital and protocol description.
  • Patient Travel Fund pays a family up to $500 for travel expenses to participate in a Clinical Trial.
  • Global network of volunteers composed of patients and family members share treatment experiences and other information regarding the physical and emotional aspects of these diseases.
  • International support groups in 50 countries provide local assistance, regional resources and personal contacts with other patients.
  • Quarterly newsletters feature medical updates, research articles, victory stories, helpful resources and Foundation activities.
  • Annual international patient conferences gather hundreds of patients and families with recognized medical researchers and health care experts to discuss research updates, advances in treatments options and other related issues.
  • AA & MDSIF Voluntary Patient Registry collects patient statistics to help medical researchers better understand the disease.
  • Medical research studies financially funded in hopes of finding a cure.
  • Medical Advisory Board composed of distinguished medical experts who advise the Foundation on research funding, educational materials, and patient information.

Leukemia Medical Glossary

  • Absolute Neutrophil Count (ANC) Common blood cell count measured after stem cell transplant. Neutrophils are responsible for a large part of the body's protection against infection.
  • Allele Two or more forms of a gene. A single allele for each gene location is inherited from parents. For example, at the gene location for hair color, the allele might result in black or brown hair. Alleles are important in molecular HLA typing (See HLA).
  • Acute Lymphoblastic Leukemia (ALL) Type of fast growing cancer of the lymphocytes, one of the white blood cells. AKA acute lymphocytic leukemia. Appears mostly in children, but can affect adults.
  • Acute Myelogenous Leukemia (AML) A cancer of the myelocytes, one of the white blood cells. AML occurs in all ages and is the more common acute leukemia in adults. AML affects a different type of white cells than those affected by ALL.
  • Acute Non-Lymphocytic Leukemia (ANLL) Another way of saying acute myelogenous leukemia (See AML).
  • Allogeneic Bone Marrow Transplant Any bone marrow/blood stem cell transplant in which the cells come from another person rather than the patient's own cells. The donated cells can come from a related or unrelated donor.
  • Anemia A condition where not enough oxygen gets to the tissues and the organs because of too few red blood cells in the blood.
  • Antibody (antibodies) Any of various proteins in the blood that are created by the immune system to neutralize foreign substances in the body. The immune system creates antibodies in response to substances in the body that contain foreign antigens, such as viruses.
  • Antigen A substance that causes a reaction from the body's immune system.
  • Apheresis A procedure where blood is drawn from a patient's or donor's arm and circulated through a machine that removes certain cells such as stem cells, white blood cells or platelets. The rest of the blood is returned to the patient or donor.
  • Aplastic anemia A condition where the bone marrow makes too few white blood cells, red blood cells and platelets.
  • Autologous Bone Marrow Transplant A bone marrow/blood stem cell transplant in which the patient's own cells are used.
  • Blast Cells Cells that are not fully formed.
  • Blast Crisis The stage of chronic myelogenous leukemia when large amounts of blast cells are found in the blood.
  • Blood Stem Cells Cells found in the blood that can grow into a red blood cell, a white blood cell or a platelet. Also called hematopoietic stem cells. (See also, Stem Cells and Embryonic Stem Cells).
  • Bone Marrow A spongy tissue inside of large bones where the body's blood cells (red cells, white cells and platelets) are made.
  • Bone Marrow Transplant (BMT) Giving healthy bone marrow to patients whose marrow is damaged. There are two types: allogeneic and autologous.
  • Catheter A needle that is inserted into a vein in the body, usually in the chest. Attached to the needle is a valve that rests outside of the body that is used to withdraw blood samples for testing.
  • Chemotherapy Drugs that kill cancer cells to prepare the patient for a blood stem cell transplant.
  • Chronic Lymphocytic Leukemia (CLL) A cancer of the lymphocytes on the white blood cells. It usually occurs in persons over the age of 60. It is more common in men.
  • Chronic Myelogenous Leukemia (CML) A cancer of the myelocytes on the white blood cells. CML can happen at any age in either males or females. It is rare before age 10 and occurs most often in persons over age 45.
  • Collection Center National Marrow Donor Program-accredited hospitals with experience and facilities to collect stem cells and care for stem cell donors before and after the stem cell donation procedure.
  • Conditioning The chemotherapy and/or radiation that is given to patients before the marrow or blood stem cell transplant. The purpose is to kill diseased cells so the new cells can grow.
  • Confirmatory Typing (CT) A repeat tissue typing test done to make sure the donor and patient match. This is one of the final tests done before transplant.
  • Congenital Disorder Any disorder present at birth.
  • Cooley's Anemia Another name for thalassemia major. (See also Thalassemia.)
  • Coordinating Center The NMDP Coordinating Center, office located in Minneapolis, Minnesota, establishes standards, policies, and procedures for its Network of Transplant, Donor, Apheresis and Collection Centers, Cord Blood Banks, Recruitment Groups and Cooperative Registries. From this office, Network Centers performance is monitored; patients' searches for compatible unrelated donors are coordinated; and communication between Network members is facilitated. The scheduling, coordination, transport and tracking of unrelated stem cell collections are managed by the Coordinating Center.
  • Cord Blood The blood of newborns found in the umbilical cord and placenta. It contains large numbers of blood stem cells. For this reason, blood stem cells from the placenta and umbilical cord are collected after birth and stored for transplant.
  • Cord Blood Bank An organization that helps to collect and store umbilical cord blood for transplant.
  • Cytomegalovirus (CMV) A virus that can cause pneumonia in blood stem cell transplant patients.
  • DNA (Deoxyribonucleic acid) Carries genetic information throughout the body.
  • DNA based HLA Typing Determining a person's HLA type by direct examination of the DNA. DNA-based typing is favored by the NMDP because it is very accurate and efficient.
  • DNA Repository See Sample Repositories.
  • Donor A volunteer who has donated stem cells for a patient.
  • Donor Center An NMDP-accredited organization with the experience, staff and facilities to recruit and manage interaction with volunteer stem cell donors listed on the Registry.
  • Donor Workup The process that a closely matched potential donor goes through to make sure he or she is healthy and ready to donate marrow or blood stem cells. Workup includes a detailed information session at the Donor Center, a complete physical examination and donation of blood samples for testing and research. Sometimes a unit of the donor's blood is saved in case it is needed later.
  • DR Typing HLA typing to determine the HLA-DR determinants carried or expressed by a donor or patient. HLA-DR typing is almost exclusively performed by DNA-based methods. (See Prospective HLA-DR typing.)
  • Embryonic Stem Cells Stem cells that come from human embryos. Stem cells from embryos are not used for marrow or blood stem cell transplants.
  • Engraftment The stage when the stem cells given during the transplant start to grow and make blood cells.
  • Epidural Anesthesia A form of anesthesia for which medication is inserted into the outer (epidural) layer of the spinal cord to block any painful sensations from the point of insertion to the lower extremities. The donor is awake with this form of anesthesia. About 20 percent of NMDP stem cell donors receive epidural anesthesia. Epidural anesthesia is a form of regional anesthesia.
  • Fanconi Anemia A rare, inherited type of aplastic anemia. Found most often in young children.
  • Filgrastim A protein that helps bone marrow make more white blood cells. Filgrastim is also known as GCSF (granulocyte-colony stimulating factor) or by the tradename Neupogen®. It is given to donors who have agreed to donate peripheral blood stem cells. This moves blood stem cells from the marrow into the blood stream so that they can be collected by apheresis. It is also given to patients to help increase their white blood cell count after the transplant.
  • Formal Search A search becomes formal when a physician at an NMDP-accredited Transplant Center asks that one or more volunteer stem cell donors who are potential matches for a patient be contacted to undergo additional compatibility testing. The Donor Center where volunteer stem cell donors are registered contacts them to arrange collection of blood samples. Once a search is formal, regular reports of the search status are sent to the Transplant Center.
  • General Anesthesia This form of anesthesia causes stem cell donors to lose consciousness, so they are unaware of the surgical procedure that removes their marrow or any other sensations. General anesthesia is used for about 75 percent of NMDP collections.
  • Genetic Factor A characteristic or trait that is influenced or encoded by one or more genes.
  • Graft failure Absent or inadequate production of white blood cells, platelets and red blood cells following a transplant.
  • Graft Versus Host Disease (GVHD) A condition where the transplanted donor marrow or blood stem cells attack the patient's body. GVHD can be mild or serious and is sometimes life threatening.
  • Growth Factor Another term used when referring to Filgrastim. (See Filgrastim.)
  • Hairy Cell Leukemia (HCL) A rare type of chronic leukemia usually found in middle-aged men. HCL rarely requires BMT as a treatment.
  • Hematopoietic The process of forming blood cells: red blood cells, white blood cells and platelets.
  • Hematopoietic Stem Cells Blood forming stem cells capable of producing all the components of blood and marrow. Cells capable of both self-renewal and differentiation to white blood cells, red blood cells, and platelets.
  • Hemoglobin The part of the red blood cell which carries oxygen.
  • Hereditary Traits that are passed down to children from their parents.
  • Histiocytosis A rare and often fatal blood disease. A type of white blood cell called a histiocyte grows wildly and attacks body organs.
  • Histocompatibility A system that determines how closely the patient and donor blood stem cells match.
  • HIV/AIDS Virus Human immunodificiency virus that causes AIDS. People with AIDS suffer infections, malignancies and neurologic disease.
  • Human Leukocyte Antigens (HLA) Proteins on white blood cells that make each person's tissue unique. The HLA A, B, C and DR proteins are important in matching patients and donors for a marrow or blood stem cell transplant.
  • HLA Alleles See Alleles.
  • HLA Typing A person's own specific HLA A, B, C and DR proteins.
  • HLA Typing Laboratories Laboratories under contract with the National Marrow Donor Program to perform HLA typing on donor or recipient blood samples.
  • Hodgkin's Disease A lymphoma that most often occurs in young adults. Hodgkin's disease that does not respond to chemotherapy may be treated by an autologous marrow or blood stem cell transplant and less often by an allogeneic marrow or blood stem cell transplant.
  • Human T-Cell Lymphotic Virus (HTLV) A rare virus transmitted by cellular components of blood. Two forms of the virus have been identified, HTLV-I and HTLV-II.
  • Immune System The combined workings of the marrow and lymphocytes, which fight to protect the body from foreign invaders.
  • Informed Consent The process by which a person receives an explanation of the risks and benefits to a medical treatment or research study and agrees to participate and indicates in writing that he or she understands and agrees to the information provided. A person can provide informed consent at the age of 18.
  • Infectious Disease Markers Elements in a person's blood which indicate if a person has had an infectious disease.
  • Infectious Disease Testing The method to determine if a person has or did have an infectious disease.
  • Leukapheresis The process of separating white blood cells from the rest of the blood. (See Apheresis.)
  • Leukemia A group of cancers of the white blood cells. Leukemias can be acute (fast forming) or chronic (slow growing). More here.
  • Lymphocyte A type of white blood cell that helps protect the body from invading organisms. T-cells are a kind of lymphocyte that causes Graft Versus Host Disease.
  • Lymphoma A cancer of the lymph tissue. Included in this disease category are Hodgkin's disease and non-Hodgkin's lymphoma.
  • Malignant Cancer cells have been found.
  • Marrow See bone marrow.
  • Marrow Donation A surgical procedure by which a person donates a portion of their bone marrow for a patient who had diseased marrow and needs a bone marrow transplant.
  • Match In a blood stem cell transplant, the match level explains how much alike the tissues of the patient and the donor are.
  • Medical Examination See Physical Examination.
  • Medical Treatment Treatment from a trained medical practitioner for a disease or condition.
  • Mixed Lymphocyte Culture (MLC) A test that shows if the patient's and donor's cells react to each other.
  • Molecular HLA Typing At the level of a molecule. Molecular HLA typing is the same as DNA typing. Molecular typing is done at the smallest level of the cells.
  • Multiple Myeloma A cancer of the plasma cells in the blood. Frequently associated with bone pain and infections. More common in males than females.
  • Myelodysplastic Syndrome or Disorder Also called pre-leukemia or "smoldering" leukemia. It is a disease of the bone marrow in which too few platelets, red blood cells and white blood cells are made.
  • Myelofibrosis A disease that causes scar tissue to form in the bone marrow. As a result of the scar tissue, normal blood cell production is blocked. Normal blood cell production then moves to the spleen which then becomes enlarged. Anemia results because blood production in the spleen does not work as well as in the bone marrow.
  • Myeloproliferative Disorder A group of disorders caused by increased production of blood cells by the bone marrow. The four types of Myeloproliferative Disorders are:
    • Polycythemia Vera: too many red blood cells
    • Chronic Myelomonocytic Leukemia: too many white blood cells
    • Primary Thrombocythemia: too many platelets
    • Myelofibrosis: a disease that causes scar tissue to form in the bone marrow
  • National Marrow Donor Program Network The Apheresis Centers, Cord Blood Banks, Recruitment Groups, Donor Transplant and Collection Centers that work with the NMDP. The NMDP Network also includes sample repositories and HLA typing laboratories under contract with the NMDP.
  • Non-Hodgkin's Lymphoma A cancer that is found in the lymph tissue.
  • Non-Myeloablative Transplant (Mini or Low Intensity Regimen) A type of transplant that uses lower doses of chemotherapy and/or radiation to prepare a patient for transplant. It relies on the immune system to kill the disease. It may be a treatment option for older patients or those with other health problems because lower doses of chemotherapy/radiation are easier for the patient to handle.
  • Neuroblastoma A cancer that occurs in children and is sometimes treated by a marrow or blood stem cell transplant.
  • Neutrophil A type of white blood cell. The number of neutrophils present in the bloodstream is often used as a measure of stem cell engraftment.
  • Oligonucleotide Sequence of nucleic acids used as a probe in DNA based tissue typing.
  • Osteopetrosis A disease of the bones where the bones get very hard and the bone marrow cannot grow.
  • Peripheral Blood Stem Cell (PBSC) Donation Hematopoietic stem cells are collected from a donor's circulating blood through an apheresis procedure following mobilization from the marrow with Filgrastim. The stem cells are then transplanted into a recipient.
  • Peripheral Blood or Peripheral Blood Stem Cells (PBSC) Peripheral blood flows through the bloodstream in the body. Some blood stem cells are found in the peripheral blood.
  • Pheresis See Apheresis.
  • Phlebotomy Withdrawing blood from a vein (usually a vein in the arm) usually for testing purposes.
  • Physical Examination A general evaluation of a person's physical condition performed by a physician or nurse.
  • Plasma The liquid portion of unclotted blood. (Serum is the liquid portion of clotted blood.)
  • Platelet A blood cell needed to control bleeding.
  • Potential Donor See Volunteer Donor.
  • Preliminary Search The process by which a patient's HLA type is sent to the NMDP and entered into the computer where it is compared to the HLA types of all volunteers listed in the Registry at that time. The patient's demographic information and basic disease status are also submitted at preliminary search. The preliminary search becomes formal when specific donors are requested for further testing on behalf of the patient.
  • Pre-transplant Conditioning A regimen of chemotherapy with or without radiation therapy that destroys a patient's marrow. The marrow is then restored by transplanting stem cells.
  • Prospective HLA-DR Typing A National Marrow Donor Program typing program that selects stored samples from donors who have been HLA-A, B typed, but not HLA-DR typed, and submits them for HLA-DR typing in advance of the donor being identified as a potential match for a specific patient. The goal of this program is to increase the number and diversity of fully HLA typed volunteer stem cell donors on the NMDP Registry, thus reducing search times and costs for patients.
  • Protocol A specific plan for treatment of a disease.
  • Radiation Therapy Treatment aimed at eliminating cancer cells, shrinking tumors or suppressing the immune system by using high-energy radiation from X-ray machines or other sources.
  • Red Blood Cell A cell that carries oxygen to all organs and tissues. Also known as an erthrocyte.
  • Recruitment Group An organization affiliated with the National Marrow Donor Program that recruits donors.
  • Registry A confidential national database of potential volunteer stem cell donors established and maintained by the National Marrow Donor Program.
  • Regional Anesthesia Includes both epidural and spinal.
  • Relapse The return of the disease after treatment.
  • Remission When cancer cells are gone after treatment.
  • Research Sample A sample of a donor's or recipient's blood that is used in research studies. Typically, blood samples are collected for research studies but sometimes a marrow sample is requested at the time of donation.
  • Retention Refers to the length of time volunteer stem cell donors remain on the Registry and are able to be located, are in good health and are still willing to donate.
  • Sample Repositories Laboratories under contract with the NMDP to store blood samples from NMDP volunteer donors for later DNA-based HLA typing.
  • Sarcoma A cancer most often found in muscle or bone.
  • Search Process The process of comparing a patient's HLA antigens to those of the volunteer donors on the Registry (preliminary search) and testing potentially matched donors to identify the best donor for the patient (formal search). The search process may take from several weeks to more than a year.
  • Serologic Testing A test using serum from the blood to find the patient's or donor's HLA typing.
  • Severe Aplastic Anemia See also Aplastic Anemia.
  • Severe Combined Immunoficiency Disease (SCID) An inherited disease in which the immune system does not work well. It is often treated with a marrow or blood stem cell transplant.
  • Sickle Cell Anemia An inherited type of anemia which occurs most often in Africans and African Americans. The disease gets its name from the sickle shape (a C-shape) of the red blood cells. These cells cannot move oxygen very well. The disease is sometimes treated with a marrow or blood stem cell transplant.
  • Sickle Cell Trait A person who has one gene for sickle cell anemia is said to have sickle cell trait. Sickle cell trait cannot change to become sickle cell anemia. A person will develop sickle cell anemia only if both parents pass on the trait (gene) to him or her.
  • Spinal Anesthesia A form of anesthesia in which medication is inserted into the spinal column to block any painful sensations that might be felt from the point of insertion down to the lower extremities. The donor is conscious under this form of anesthesia. Nearly five percent of NMDP donors receive spinal anesthesia.
  • Search, Tracking and Registry (STARĀ®) System A computerized system used to manage all patient follow-up histories and maintain the volunteer donor Registry.
  • Stem Cells A common word for any of the cells in the body that can grow into other kinds of cells. In blood stem cell transplants, blood stem cells are given to the patient after they are treated for the disease of the bone marrow. See also Blood Stem Cells, Embryonic Stem Cells and Hematopoietic Stem Cells.
  • Stem Cell Transplant The process of infusing healthy stem cells into persons who have undergone high-dose chemotherapy for one of many forms of leukemia, immunodeficiency, lymphoma, anemias, or metabolic disorders. There are three types of stem cell transplants: autologous, allogeneic and syngeneic. Healthy stem cells are collected from bone marrow, peripheral blood, and umbilical cord blood. Once the healthy stem cells are infused into the patient's blood stream, the cells move from the blood vessels to the center of the bones, where they begin making new blood cells. (See Autologous, Allogeneic, and Syngeneic.)
  • Syngeneic Stem Cell Transplant A marrow or blood stem cell transplant from one identical twin to the other.
  • Syringe An instrument consisting of a hollow barrel and a plunger used to administer injections or to hold the liquid resulting from an aspiration.
  • T Cell A type of white blood cell.
  • Thalassemia A group of chronic, inherited anemias. Most often found in persons of Mediterranean, African and Southeast Asian descent.
  • Tissue Typing Another term for HLA-typing.
  • Transplant A medical treatment to replace a recipient's diseased organ with a healthy organ from a donor.
  • Transplant Center NMDP-accredited, hospital based programs with experience, staff and facilities to perform allogeneic stem cell transplantation.
  • Tumor Any abnormal growth of cells. Tumors can be caused by cancer cells or non-cancer cells.
  • Typing See HLA Typing.
  • Typing Laboratory A testing facility that performs HLA typing.
  • Umbilical Cord Blood Stem Cell A stem cell from the blood of the umbilical cord and placenta. These cells have the potential to produce all the components of blood in the same manner as stem cells derived from marrow.
  • Unrelated Bone Marrow or Blood Stem Cell Transplant A marrow or blood stem cell transplant where the donor is not related to the patient.
  • Volunteer Donor A person who has agreed to donate marrow or stem cells for transplant. Volunteer donors are listed in the NMDP Registry.
  • White Blood Cell One of three main types of blood cells, along with red blood cells and platelets. White blood cells help protect the body from infection.
  • Wiskott-Aldrich Syndrome An inherited disease of the immune system that only occurs in boys. The white blood cells can not fight infection. The number of platelets are low and of small size. Because of the low number of platelets, patients have many infections, bleed easily and often have a skin rash. A bone marrow transplant is the best known treatment for this disease.
  • Workup The process that a closely matched potential donor undergoes to determine whether he or she is healthy and prepared to donate stem cells. Workup includes a detailed information session with a Donor Center coordinator and/or medical director, a thorough physical examination, a donation of additional blood samples for testing and research and usually a donation of autologous blood.

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