Transplant
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
Anemia. This information is from the Schneider
Children's Hospital Website. I did not write this
article, but am providing it here as information for
those who are unfamiliar with Bone Marrow
Transplant.
What is a bone marrow transplantation?
Bone marrow transplantation (BMT) is a special therapy for patients with cancer or other
diseases which affect the bone marrow. A bone marrow transplant involves taking cells that
are normally found in the bone marrow (stem cells), filtering those cells, and giving them
back either to the patient or to another person. The goal of BMT is to transfuse healthy
bone marrow cells into a person after their own unhealthy bone marrow has been eliminated.
What is bone marrow?
The bone marrow is a soft, spongy tissue found inside the bones. The bone marrow in the
hips, breast bone, spine, ribs, and skull contain cells that produce the body's blood cells.
The bone marrow is responsible for the development and storage of about 95 percent of
the body's blood cells. The three main types of blood cells produced in the bone marrow
include:
* red blood cells (erythrocytes) - carry oxygen to the tissues in the body.
* white blood cells (leukocytes) - help fight infections and to aid in the immune system.
* platelets - help with blood clotting.
Each of these cells carries a life-maintaining function. The bone marrow is a vital part of the
human body.
What are stem cells?
Every type of blood cell in the bone marrow begins as a stem cell. Stem cells are immature
cells that are able to produce other blood cells that mature and function as needed.
Stem cells are the most important cells needed in a bone marrow transplant. Stem cells,
when transplanted, find their way to the recipient's marrow and begin to differentiate and
produce all types of blood cells that are needed by the body.
Why is a bone marrow transplant needed?
The goal of a bone marrow transplant is to cure many diseases and types of cancer. When
a child's bone marrow has been damaged or destroyed due to a disease or intense
treatments of radiation or chemotherapy for cancer, a marrow transplant may be needed.
A bone marrow transplant can be used to:
* replace diseased, non-functioning bone marrow with healthy functioning bone marrow (for
conditions such as leukemia, aplastic anemia, and sickle cell anemia).
* replace the bone marrow and restore its normal function after high doses of chemotherapy
or radiation are given to treat a malignancy. This process is often called "rescue" (for
diseases such as lymphoma, neuroblastoma, and breast cancer).
* replace bone marrow with genetically healthy functioning bone marrow to prevent further
damage from a genetic disease process (such as Hurler's syndrome, and
adrenoleukodystrophy).
Bone marrow transplantation has risks involved, some of which are life threatening. The
risks and benefits must be weighed in a thorough discussion with the bone marrow
transplant team prior to the procedure.
Each child experiences diseases differently and a bone marrow transplantation may not be
appropriate for everyone who suffers from these diseases. Some of the diseases that have
been treated with bone marrow transplant include the following:
* leukemia
* lymphomas
* some solid tumors (i.e., neuroblastoma, rhabdomyosarcoma, brain tumors)
* aplastic anemia
* immune deficiencies (severe combined immunodeficiency disorder, Wiskott-Aldrich
syndrome)
* sickle cell disease
* thalassemia
* Blackfan-Diamond anemia
* metabolic/storage diseases (i.e., Hurler's syndrome, adrenoleukodystrophy disorder)
* cancers of the breast, ovaries, and kidneys
What are the different types of bone marrow transplants?
There are different types of bone marrow transplants depending on who the donor is. The
different types of bone marrow transplant include the following:
* autologous bone marrow transplant
The donor is the child him/herself. Stem cells are taken from the child either by bone
marrow harvest or apheresis (peripheral blood stem cells) and then given back to the child
after intensive treatment. Often the term "rescue" is used instead of "transplant."
* allogeneic bone marrow transplant
The donor shares the same genetic type as the child. Stem cells are taken either by bone
marrow harvest or apheresis (peripheral blood stem cells) from a genetically-matched
donor, usually a brother or sister. Other donors for allogeneic bone marrow transplants
include:
o a parent - a haploid-identical match is when the donor is a parent and the genetic match
is at least half identical to the recipient.
o an identical twin - a syngeneic transplant is an allogeneic transplant from an identical twin.
Identical twins are considered a complete genetic match for a marrow transplant.
o unrelated bone marrow transplants (UBMT or MUD for matched unrelated donor) - the
genetically matched marrow or stem cells are from an unrelated donor. Unrelated donors
are found through the national bone marrow registries.
* umbilical cord blood transplant
Stem cells are taken from an umbilical cord immediately after delivery of an infant. These
stem cells reproduce into mature, functioning blood cells quicker and more effectively than
do stem cells taken from the bone marrow of another child or adult. The stem cells are
tested, typed, counted, and frozen until they are ready to be transplanted.
Because the stem cells are "new," they are able to produce more blood cells from each
stem cell. Another advantage cord blood has is that the T-lymphocytes (part of the immune
system that causes graft-versus-host disease) are not completely functional this early in the
stage of life. Recipients of cord blood transplants have a decrease risk for severe
graft-versus-host disease.
The bone marrow transplant team:
The group of specialists involved in the care of children going through transplant is often
referred to as the "transplant team." Each individual works together to provide the best
chance for a successful transplant. The team consists of:
* physicians - physicians who specialize in oncology, hematology, immunology, and bone
marrow transplantation.
* bone marrow transplant nurse coordinator - a nurse who organizes all aspects of care
provided to your child before and after the transplant. The nurse coordinator will provide
patient education, and coordinates the diagnostic testing and follow-up care.
* social workers - professionals who will help your family deal with many issues that may
arise including lodging and transportation, finances, and legal issues. They can also help
coordinate alternative means for school, so that your child does not get behind.
* dietitians - professionals who will help your child meet his/her nutritional needs before and
after the transplant. They will work closely with you and your family.
* physical therapists - professionals who will help your child become strong and
independent with movement and endurance after the transplantation.
* pastoral care - chaplains who provide spiritual care and support.
* other team members - several other team members will evaluate your child before
transplantation and will provide follow-up care as needed. These include, but are not limited
to, the following:
o pharmacists
o respiratory therapists
o lab technicians
o infectious disease specialists
o dermatologists
o gastroenterologists
o psychologists
An extensive evaluation is completed by the bone marrow transplant team. The decision for
your child to undergo a bone marrow transplant will be based on many factors including:
* your child's age, overall health, and medical history
* extent of the disease
* availability of a donor
* your child's tolerance for specific medications, procedures, or therapies
* expectations for the course of the disease
* expectations for the course of the transplant
* your opinion or preference
Preparation for the recipient:
For the child receiving the transplant, the following will occur in advance of the procedure:
* Prior to the transplant, an extensive evaluation is completed by the bone marrow
transplant team. All other treatment options are discussed and evaluated for risk versus
benefit.
* A complete medical history and physical examination are performed, including multiple
tests to evaluate the child's blood and organ functions (i.e., heart, kidney, liver, lungs).
* A child will often come into the transplant center up to 10 days prior to transplant for
hydration, evaluation, placement of the central venous line, and other preparations. A
catheter, also called a central venous line, is surgically placed in a vein in the chest area.
Blood products and medications will be administered through the catheter.
* A suitable (tissue typed and matched) donor must be available. Finding a matching donor
can be a challenging and lengthy process. Voluntary marrow donors are registered in
several national and international registries. A bone marrow search involves searching
these registries for donors whose blood most closely resembles or matches the child
needing the transplant.
Preparation for the donor:
* Donor sources available include: self, sibling, parent or relative, non-related person, or
umbilical cord from a related or non-related person. There are national and international
registries for non-related persons and cord blood. For family members, they may be typed
because of the desire to help. These relatives may or may not elect to have their type
registered for use with other recipients.
* If the potential donor is notified that they may be a match for a child needing a transplant,
they will undergo additional tests. Tests related to their health, exposure to viruses, and
complete genetic analysis will be done to determine the extent of the match. The donor will
be given instructions on how a bone marrow donation will be made.
* Once a match for a child needing a bone marrow transplant is found, then stem cells will
be collected either by a bone marrow harvest (collection of stem cells with a needle placed
into the soft center of the bone marrow) or peripheral blood stem cell collection (stem cells
are collected from the circulating cells in the blood). Cord blood has already been collected
at the time of a birth and stored for later use.
How are a donor and recipient matched?
Matching involves typing human leukocyte antigen (HLA) tissue. The antigens on the
surface of these special white blood cells determine the genetic make-up of a person's
immune system. There are at least 100 HLA antigens, however, it is believed that there are
a few major antigens that determine whether a donor and recipient match. The others are
considered minor and their effect on a successful transplant is not as well defined.
Medical research is still investigating the role all antigens play in the process of a bone
marrow transplant. The more antigens that match, the better the engraftment of donated
marrow. Engraftment of the stem cells occurs when the donated cells make their way to the
marrow and begin reproducing new blood cells.
How are the stem cells collected?
A bone marrow transplant is done by transferring stem cells from one person to another.
Stem cells can either be collected from the circulating cells in the blood (the peripheral
system) or from the bone marrow.
* peripheral blood stem cells (PBSCs)
Peripheral blood stem cells (PBSCs) are collected by a apheresis, a process in which the
donor is connected to a special cell separation machine via a needle inserted in the vein.
Blood is taken from one vein and is circulated though the machine which removes the stem
cells and returns the remaining blood and plasma back to the donor through another
needle inserted into the opposite arm. Several sessions may be required to collect enough
stem cells to assure a chance of successful engraftment in the recipient.
A medication may be given to the donor for about one week prior to apheresis that will
stimulate the bone marrow to increase production of new stem cells. These new stem cells
will be released from the marrow and into the circulating or peripheral blood system.
* bone marrow harvest
Bone marrow harvesting involves collecting stem cells with a needle placed into the soft
center of the bone, the marrow. Most sites used for bone marrow harvesting are located in
the hip bones and the sternum. The procedure takes place in the operating room. The
donor will be anesthetized during the harvest and will not feel the needle. In recovery, the
donor may experience some pain in the areas where the needle was inserted.
If the donor is the child him/herself it is called an autologous bone marrow transplant. If an
autologous transplant is planned, previously collected stem cells, from either peripheral
(apheresis) or harvest, are counted, screened, and ready to infuse.
For umbilical cord blood transplants, blood has been collected at the time of a birth and
stored. Cord blood is collected after delivery, when the placenta and umbilical cord are
separated from the infant. The site of collection is cleaned to prevent bacteria from entering
the collection process. The blood that is contained in the cord is collected in a sterile
container. The blood is then tested for type and the presence of viruses or disease, and the
stem cells are counted. The cord blood is then stored in special freezers and is registered
in a national registry for potential recipient matches.
The bone marrow transplant procedure:
The preparations for a bone marrow transplant vary depending on the type of transplant,
the disease requiring transplant, and your child's tolerance for certain medications.
Consider the following:
* Most often, high doses of chemotherapy and/or radiation are included in the preparations.
This intense therapy is required to effectively treat the malignancy and make room in the
bone marrow for the new cells to grow. This therapy is often called ablative, or
myeloablative, because of the effect on the bone marrow. The bone marrow produces all
the blood cells in our body. Ablative therapy prevents this process of cell production and
the marrow becomes empty. An empty marrow is needed to make room for the new stem
cells to grow and establish a new production system.
* After the chemotherapy and/or radiation is administered, the marrow transplant, either
from bone marrow, cord, or from peripherally collected stem cells, is given through the
central venous catheter into the bloodstream. It is not a surgical procedure to place the
marrow into the bone, but is similar to receiving a blood transfusion. The stem cells find
their way into the bone marrow and begin reproducing and establishing new, healthy blood
cells.
* Supportive care is given to prevent and treat infections, side effects of treatments, and
complications. This includes frequent blood tests, close monitoring of vital signs, strict
measurement of input and output, weighing your child daily (or twice daily), and providing a
protected and sterile environment.
The days before transplant are counted as minus days. The day of transplant is considered
day zero. Engraftment and recovery following the transplant are counted as plus days. For
example, a child may enter the hospital on day -8 for preparative regimen. The day of
transplant is usually numbered as day 0. Days +1, +2, etc.) will follow. There are specific
events, complications, and risks associated with each day before, during, and after
transplant. The days are numbered to help the child and family understand where they are
in terms of risks and discharge planning.
During infusion of bone marrow, your child may experience any, or all, of the following
symptoms:
* pain
* chills
* fever
* hives
* chest pain
After infusion, your child may:
* spend several weeks in the hospital.
* be very susceptible to infection.
* experience excessive bleeding.
* have blood transfusions.
* be confined to a sterile environment.
* take multiple antibiotics and other medications.
* be given medication to prevent graft-versus-host disease (if the transplant was
allogeneic). The transplanted new cells (the graft), tend to attack the child's tissues (the
host), even though the donor is a relative, such as a brother, sister, or parent.
* undergo continual laboratory testing.
* experience nausea, vomiting, diarrhea, mouth sores, and extreme weakness.
* experience temporary emotional or psychological distress.
Your child's physical and mental health are important in the success of a transplant. Every
measure is taken to minimize complications and promote a healthy, happy, safe
environment for your child.
When does engraftment occur?
Engraftment of the stem cells occurs when the donated cells make their way to the marrow
and begin reproducing new blood cells. Depending on the type of transplant and the
disease being treated, engraftment usually occurs around day +15 or +30. Blood counts will
be performed frequently during the days following transplant to evaluate initiation and
progress of engraftment. Platelets are generally the last blood cell to recover.
Engraftment can be delayed because of infection, medications, low donated stem cell count,
or graft failure. Although the new bone marrow may begin making cells in the first 30 days
following transplant, it may take months, even years, for the entire immune system to fully
recover.
What complications and side effects may occur following BMT?
The following are complications that may occur with a bone marrow transplantation.
However, each child may experience symptoms differently. Complications may vary
depending on the following:
* type of marrow transplant
* type of disease requiring transplant
* preparative regimen
* age and overall health of the recipient
* variance of tissue matching between donor and recipient
* presence of severe complications
Possible complications may include, but are not limited to, the following. These
complications may also occur alone, or in combination:
* infections
Infections are likely in the child with severe bone marrow suppression. Bacterial infections
are the most common. Viral and fungal infections can be life threatening. Any infection can
cause an extended hospital stay, prevent or delay engraftment, and/or cause permanent
organ damage. Antibiotics, anti-fungal medications, and anti-viral medications are often
given to prevent serious infection in the immuno-suppressed child.
Preventative measures for common sources of infection are also a part of transplant. This
may include any, or all, of the following:
o specially filtered rooms
o diet restrictions
o isolation requirements
o restriction of visitors
o strict hygiene regimen
o frequent linen changes
Blood tests are performed to prevent, detect, and treat infections. Often, multiple antibiotics
are started if an infection is suspected.
* low platelets and low red blood cells
Thrombocytopenia (low platelets) and anemia (low red blood cells), as a result of a
non-functioning bone marrow, can be dangerous and even life threatening. Most children
will require multiple blood product transfusions. Low platelets can cause dangerous
bleeding in the lungs, gastrointestinal (GI), and brain. Until the stem cells begin making new
blood cells, GI tract therapy is needed to prevent injuries and to treat anemia.
* pain
Pain related to mouth sores and gastrointestinal (GI) irritation is common. High doses of
chemotherapy and radiation can cause severe mucositis (inflammation of the mouth and GI
tract). Without the normal immune system functioning, your child is unable to heal these
irritations quickly. Often, pain medication is required. Mouth care is needed to prevent
infection and injury when mucositis is expected.
Diarrhea, nausea, and vomiting may occur with chemotherapy, radiation, and/or GI irritation.
Calories and proteins may be given through an intravenous (IV) line until your child is able
to eat again and the diarrhea has resolved.
* fluid overload
Fluid overload is a complication that can lead to pneumonia, liver damage, and high blood
pressure. The primary reason for fluid overload is because the kidneys cannot keep up with
the large amount of fluid being given in the form of medications, intravenous (IV) and
nutrition, and blood products. The kidneys may also be damaged from disease, infection,
chemotherapy, radiation, or antibiotics.
During transplant and recovery, your child will be assessed for signs and symptoms of fluid
overload. He/she may be weighed at least daily, often twice or three times daily, and blood
chemistries and input and output will be measured frequently. Medications that help kidney
function and elimination of excess fluid may be given.
* respiratory distress
Respiratory status is an important function that may be compromised during transplant.
Infection, inflammation of the airway, fluid overload, graft-versus-host disease, and bleeding
are all potential life-threatening complications that may occur in the lungs and pulmonary
system.
Close monitoring of your child's respiratory status may include:
o chest x-rays - a diagnostic test which uses invisible electromagnetic energy beams to
produce images of internal tissues, bones, and organs onto film.
o pulse oximetry - an oximeter is a small machine that measures the amount of oxygen in
the blood. To obtain this measurement, a small sensor (like a Band-Aid®) is taped onto a
finger or toe. When the machine is on, a small red light can be seen in the sensor. The
sensor is painless and the red light does not get hot.
o supplemental oxygen
* organ damage
The liver and heart are important organs that may be damaged during the transplantation
process. Temporary or permanent damage to the liver and heart may be caused by
infection, graft-versus-host disease, high doses of chemotherapy and radiation, or fluid
overload.
Close monitoring of your child's blood work and vital signs is important in minimizing and
detecting any organ damage that has occurred.
* graft failure
Graft failure is a potential complication. Graft failure may occur as a result of infection,
recurrent disease, or if the stem cell count of the donated marrow was insufficient to cause
engraftment.
Graft failure may be treated with an additional marrow transplant if a source is available.
* graft-versus-host disease
Graft-versus-host disease (GVHD) can be a serious and life-threatening complication of a
bone marrow transplant. GVHD occurs when the donor's immune system reacts against the
recipient's tissue. The new cells do not recognize the tissues and organs of the recipient's
body. The most common sites for GVHD are GI tract, liver, skin, and lungs.
GVHD is graded from I to IV and can be acute (occurs suddenly) or chronic (occurs over a
period of time). Your child will be monitored closely for signs and symptoms of GVHD.
Diarrhea, fever, rash, skin changes, abdominal pain, respiratory complications, and
decreased liver function may be present with GVHD.
Medications will be given prior to transplant to reduce the risk of this complication.
When will my child be discharged?
When your child is discharged following a bone marrow transplant depends on many
factors, including the following:
* extent of engraftment
* presence of complications
* your child's overall health
* distance from the facility (this may be specified by your child's team of physicians.
Occasionally, a bone marrow transplant patient will be required to stay within a certain
distance or travel time from the facility to ensure safety if complications arise.)
Frequent visits to your child's transplant team will be required to determine effectiveness of
treatment, detect complications, detect recurrent disease, and to manage the late effects
associated with a bone marrow transplant. The frequency and duration of visits will be
determined by your child's transplant team.
Long-term outlook for a bone marrow transplantation:
Prognosis greatly depends on the following:
* type of marrow transplant
* type and extent of the disease being treated
* disease response to treatment
* genetics
* age and overall health of the child
* your child's tolerance of specific medications, procedures, or therapies
* severity of complications
As with any procedure such as bone marrow transplant, prognosis, and long-term survival
can vary greatly from child to child. The amount of transplants occurring for an increased
number of diseases and medical developments has greatly improved the outcome for bone
marrow transplant in children and adults. Continuous follow-up care is essential for the child
following a bone marrow transplant. New methods to improve treatment and to decrease
complications and side effects of a bone marrow transplant are continually being discovered.
Support
Transplant Link