The Blood and Marrow Transplant Program at UCSF Benioff Children's Hospital is a leader in special treatment options for children with primary immunodeficiency diseases, marrow failure syndromes, genetic diseases, cancers and other life-threatening illnesses.

Below is a glossary of common terms used when discussing the bone marrow transplant (BMT) process.



A drug used specifically against and for the prevention of herpes virus; given IV or orally.


Allogeneic Transplant:

A transplant between 2 individuals who are not genetically identical.



Hair loss



A drug used specifically against fungal infections: given IV.



Absolute Neutrophil Count represents the total number of white cells that are capable of fighting bacterial infections.



A condition in which blood has a low number of red blood cells. Signs and symptoms of anemia may include: fatigue, weakness, pale color, headaches, dizziness, low blood pressure and elevated heart rate.



Protein substances in the blood stream that react against bacteria, viruses and other materials harmful to the body.



Drugs used to fight infections.



A chemical (sometimes a protein) recognized by the body's immune system as being foreign.


Aplastic anemia:

A disease where the bone marrow does not produce an adequate number of red cells, white cells and platelets.



Anti-thymocyte globulin is an antibody made in horses or rabbits against T-cells and used to increase the likelihood of engraftment in bone marrow transplant recipients or to treat graft vs. host disease.


Autologous transplant:

A transplant in which the donor and recipient are the same person.



A medication taken IV/orally to prevent gastrointestinal infections as well as a type of lung infection called pneumocystis.



Brown soap that effectively kills germs when applied to the skin.



The removal of a small piece of tissue from the body for purposes of diagnosis (i.e., bone marrow, skin, liver, lung).


Blood type:

Blood cells contain factors that are not the same in all people. Before a transfusion can occur, blood samples from the donor and recipient are classified as type A, B, AB, or 0. Another test called "cross match" ensures the compatibility of the blood between donor and recipient.



Bone Marrow Transplant Unit


Bone marrow:

A spongy material found in the center of the bones that contains stem cells that manufacture blood cells. The 3 major types of blood cells that bone marrow stem cells produce are red blood cells (RBC), white blood cells (WBC) and platelets. Each has an important function. See red blood cell, white blood cell and platelets.


Bone Marrow Transplant (BMT):

A procedure in which bone marrow stem cells are collected from one individual (the donor) and given to another (the recipient). The stem cells can be collected either directly from the bone marrow or from the blood by a procedure called leukapheresis. Sometimes the patient serves as his or her own bone marrow stem cell donor.



A chemotherapy drug that is given prior to bone marrow transplantation.



Diseases that are characterized by the uncontrolled and abnormal growth of cells. Examples: leukemia, lymphoma, and neuroblastoma.



The Complete Blood Count includes the level of hemoglobin and number of red and white blood cells and platelets in the blood.



A unique marker that is found on the surface of bone marrow stem cells. Special chemicals called monoclonal antibodies can be used to identify the CD34 positive stem cells in the bone marrow or blood. CD34 positive stem cells can be purified and T cell depleted for transplantation from donors who are mismatched (haplocompatible) with the recipient.


Central line or catheter:

A central line or central venous catheter is a soft flexible tube that is placed under the skin and then directed into a large vessel leading into the heart. The catheter allows fluids, medications, nutrition and blood products to be given without sticking the patient with a needle. Blood can also be drawn through the catheter for laboratory tests. The catheter may have either one or two tubes or lumen.



Drugs primarily used to destroy cancer cells but also used in bone marrow transplant patients without cancer in order to ensure successful engraftment. These drugs have side effects that affect other normal cells in the body. Another name commonly used is "chemo."



The state in which donor cells have durably engrafted in the recipient. Full donor chimerism implies that 100% of bone marrow and blood cells are of donor origin, while mixed or partial chimerism means that recipient cells are also present.



Anti-fungal agent. See Mycostatin.


Conditioning regimen:

Term used for those chemotherapy drugs and sometimes radiation that collectively prepare the body for transplant. The conditioning regimen usually takes 6-8 days to complete.



A laboratory procedure in which samples of blood, urine or other body fluid are used to determine the presence of an infection.



The family member (parent, brother or sister) or unrelated volunteer who donates his/her bone marrow stem cells. Sometimes the patient serves as his or her own donor. On the day of transplant, the donor either goes to the operating room and under general anesthesia has multiple bone marrow aspirations (bone marrow harvest) to remove a portion of bone marrow, or undergoes a procedure called leukapheresis to collect bone marrow stem cells from the blood.



Electrocardiogram - a machine that records electrical measurements of the heart's impulses.



The successful growth of donor bone marrow stem cells in the recipient.



Red blood cells.



An immunosuppressive chemotherapy drug that is given prior to transplant in order to prevent rejection of the donor cells by the recipient's immune system.


Gastrointestinal (GI):

Pertains to the digestive tract which includes the mouth, throat, esophagus, stomach, small and large intestine and rectum.



Granulocyte Colony Stimulating Factor. A drug that is found naturally in the body and that stimulates the production of granulocytes (neutrophils) by the bone marrow. GCSF is also used to increase the number of stem cells circulating in the blood.


Graft vs. Host Disease

A reaction between the transplanted T lymphocytes of the donor (graft) and the tissues/organs of the patient (host). The T- cells of the donor graft can attack the recipient's tissues. The skin, GI tract, liver and other organs can be affected.



A type of white blood cell that helps fight infections.



When the donor and recipient share half of their HLA antigens. All parents are haplocompatible with their children since children inherit half of their HLA antigens from their mother and half from their father.



A measure of red blood cell volume. A normal hematocrit (Hct) is between 36-48. A low Hct (for example <20) may result in the need for a red blood cell transfusion.



The branch of medicine that studies and treats diseases of the blood and blood forming organs. A hematologist is a physician that specializes in this area of practice.



Referring to the tissue that produces the components in the blood including red cells, white cells and platelets, that is, bone marrow. Another term for a bone marrow transplant (BMT) is "hematopoietic stem cell transplant (HSCT)"



A measure of red blood cell volume.



A disorder of the bone marrow cells that produce erythrocytes (red blood cells). Two hemoglobinopathies for which a bone marrow transplant is commonly done are thalassemia major and sickle cell disease.



Refers to a large amount of blood loss over a short period of time.


HEPA filter:

A High Efficiency Particulate Aerosol filter found in each of the transplant rooms which prevents harmful germs from entering the room via the air system.



The degree of tissue similarity between the donor and recipient that will determine how easily the donor cells will be accepted and/or the likelihood and severity of GVHD.


Histocompatibility (HLA) typing:

Blood tests of the tissue typing system. The HLA and MLC determine the likeness between potential donor - recipient pairs.



Human Leukocyte Antigen. See histocompatibility typing.



Intravenous administration of nutrients needed by the body. It is also called total parenteral nutrition (TPN). The nutrients in the form of fluid are given through the central line.


Immune system:

The body's system of defenses against disease. The immune system is primarily composed of white blood cells and antibodies.



A branch of medicine which studies the body's natural defense mechanisms against disease. An immunologist is a physician that specializes in this area of practice.



The state where the body has a reduced ability to adequately fight infections.



Invasion of any part of the body by germs. Bacteria, viruses, and fungi are the major germs that infect transplant recipients.


Informed consent:

The process whereby a patient/parent/legal guardian is given information about a specific surgery or treatment (i.e., bone marrow transplant). All potential risks and benefits must be understood prior to the signing of a consent form. It is a legal document that gives the physician permission to perform the procedure.



Usually given in conjunction with hyperalimentation. This IV solution contains fat and provides the body with needed nutrients.


Intravenous (IV):

The administration of fluids/medications directly into a vein.



Procedures (for example, handwashing) in the transplant rooms that minimize the exposure of transplant patients to infection.


IV pump:

The machine that delivers fluids and medications intravenously.



Refers to the veins in the neck in which catheters may be placed for leukapheresis procedures.


Kostmann's syndrome:

An inherited disorder of neutrophils in which affected children present with severe infections and very low to absent neutrophil counts; also called severe congenital neutropenia.



A procedure that is used to collect bone marrow stem cells from the blood (see PBSC). Typically, the donor of the PBSC is treated prior to the procedure with several days of GCSF injections to mobilize the bone marrow stem cells into the circulating blood. The blood is then passed through a machine that collects that part of the blood containing the stem cells. The remaining blood is returned to the donor.



A cancer of the bone marrow that is characterized by the abnormal growth of white blood cells.



A type of white blood cell.



Liver function tests are measurements from blood samples that reveal how well the liver is working.



A type of white blood cell that is especially important in fighting viral and bacterial infections as well as in rejecting transplants.



Cancer of the lymph nodes.



Refers to cancers in which there has been spreading to distant parts of the body from the original or primary site of the tumor.



Mixed Lymphocyte Culture. Sometimes used in histocompatibility typing in which donor and recipient cells are mixed together in a test tube to determine their compatibility with each other.



The process of conditioning or preparing a patient for a bone marrow transplant in which the bone marrow stem cells are destroyed or ablated. Generally, the conditioning regimen contains very high doses of chemotherapy and often total body irradiation.



A type of cancer that involves the adrenal gland or nervous system.



A type of white blood cell that plays a major role in fighting bacterial and fungal infections.



The conditioning regimen prior to transplant in which limited amounts of chemotherapy are administered in order to prevent rejection of the donor bone marrow stem cells without destroying the recipient's bone marrow.



A medication specifically used to fight a fungal or yeast infection.



The study and treatment of cancer. An oncologist is a physician who specializes in this area of practice.


PBSC (peripheral blood stem cells):

Peripheral Blood Stem Cells. These are bone marrow stem cells that are circulating in the blood and can be collected by leukapheresis. To increase the number of PBSC donors receive GCSF for several days prior to the leukapheresis.



The measurement of how a drug is taken up and eliminated by the body. The pharmacokinetics of busulfan is measured in a child who is going to receive this drug as part of his or her conditioning regimen in order to determine the optimal dose for that child.


Phenytoin (Dilantin):

A drug used to help prevent seizures. Patients are put on this while they are receiving Busulfan, a chemotherapy that can cause seizures.



Pediatric Intensive Care Unit.



A type of blood cell that is necessary to stop bleeding and allow injured areas to form clots. A normal platelet count is 140,000-300,000. A platelet transfusion may be needed with platelet counts <15,000 or to help stop bleeding.


Quinton catheter:

A type of temporary central venous catheter that is inserted into a large vein in the neck and used for leukapheresis. A similar type of central venous catheter for leukapheresis is a Vascath. Both catheters are usually removed after the leukaphersis is complete.



A unit of measurement in the administration of radiation.


Radiation Therapist:

A physician who specializes in the use of radiation in the treatment of diseases.


Radiation Therapy:

Treatment using high energy radiation. (See total body irradiation).


Red Blood Cells (RBC):

Cells found in the blood responsible for carrying oxygen to tissues in the body.


Severe Combined Immunodeficiency Disease (SCID):

A group of inherited diseases characterized by severely abnormal lymphocytes and the inability to make antibodies. Children with SCID are susceptible to infections from bacteria, viruses, and fungi which are ultimately fatal without a bone marrow stem cell transplant.


Stem cells:

The youngest bone marrow cell from which other bone marrow cells are formed.


Syngeneic Transplant:

A transplant between identical twins.


Total Body Irradiation (TBI):

Treatment using radiation to kill cancer cells and/or prepare the body for transplant by destroying diseased cells and suppressing the recipient’s immune system’s ability to reject the donor cells.



A procedure that supplies the body with a specific types of blood cells (red blood cells or platelets) that are low in number.


Umbilical cord blood:

The blood that is collected from the placenta after the umbilical cord is separated from a newborn baby. This blood contains large numbers of bone marrow stem cells and can be used as a source of donor cells from a sibling or unrelated donor for a bone marrow transplant.



A temporary central venous catheter that is used for leukapheresis procedures. It is usually inserted into a large vein in the neck or the groin and removed once the procedure is over.


Veno-occlusive disease (VOD):

A severe complication following a bone marrow transplant in which there is progressive liver failure. VOD may be mild and resolve without any treatment or may be severe and often fatal.



Referring to veins in the body that carry blood from all of the organs and tissues back to the heart. Central lines and leukapheresis catheters are venous catheters, i.e., they are placed in large veins.


White blood cells (WBC):

Cells found in the blood and tissues that aid in fighting infections and making antibodies for the immune system's attack against disease. There are several types of white blood cells including neutrophils and lymphocytes. The normal WBC is 5,000-10,000


Xenogeneic transplant:

A transplant between two different species, for example, bone marrow from a baboon transplanted into a human.



A germ that can infect recipients of bone marrow transplants. One kind of yeast or fungus is Candida. Fluconozole is an antibiotic that is given during the transplant period to reduce the risk of fungal infections. Yeast or fungal infections are very dangerous and when yeast is cultured or a yeast infection is suspected a very powerful antibiotic, amphoteracin is usually administered.



A viral infection that may occur post bone marrow transplant in a patient who has previously had chicken pox. Zoster or shingles is the reactivation of the chicken pox virus (varicella).

To learn more about BMT at UCSF Benioff Children's Hospital, please visit the following sections: