What is a bone marrow transplant for children?

A bone marrow transplant (BMT) is a treatment for children with certain types of cancer or other diseases. The goal of BMT is to replace a child’s diseased bone marrow with healthy bone marrow.

Bone marrow is the spongy material in the center of the bones that makes all types of blood cells, including young blood cells called stem cells. In BMT, stem cells are filtered, and then put back into the same child. Or they are put into another sick child. These stem cells will grow and become new and healthy bone marrow. Transplanted stem cells are called the graft.

There are different types of BMT based on how the healthy stem cells are collected.

Why might my child need a bone marrow transplant?

The goal of BMT is to cure many diseases and certain types of cancer. It can be used to:

• Replace diseased bone marrow with healthy bone marrow. This is done for conditions, such as leukemia, aplastic anemia, and sickle cell anemia.

• Replace bone marrow after high doses of chemotherapy or radiation are given to treat cancer. This process is often called rescue instead of transplant. This is done for diseases like lymphoma and neuroblastoma.

• Replace bone marrow with healthy bone marrow to prevent more damage from a genetic disease. This is done for diseases, such as Hurler syndrome and adrenoleukodystrophy disorder.

Diseases that can be treated with BMT include:

• Cancers, such as leukemia, lymphoma, neuroblastoma, rhabdomyosarcoma, brain tumors, or kidney cancer

• Aplastic anemia

• Immune deficiency, such as severe combined immunodeficiency disorder or Wiskott-Aldrich syndrome

• Genetic diseases, such as sickle cell disease, thalassemia, Diamond Blackfan anemia, Hurler syndrome, or adrenoleukodystrophy disorder

What are the risks of a bone marrow transplant for a child?

A bone marrow transplant has risks, some of which are life-threatening. Your child’s healthcare provider and BMT team will discuss risks and benefits with you before the procedure.

Risks and complications may vary depending on:              

• The type of BMT

• The type of disease the transplant is treating

• What medicines are used before the transplant

• Your child’s age and overall health

• The differences of the tissue match between donor and recipient

Possible complications include:

• Infections. Infections are likely with severe bone marrow suppression. This is when not enough blood cells are made in the bone marrow. Medicines are often given to prevent and treat infection.

• Low levels of platelets (thrombocytopenia) and red blood cells (anemia). These can be dangerous and even life-threatening. Most children will need multiple blood product transfusions.

• Pain. Pain caused by mouth sores and gastrointestinal (GI) irritation is common from chemotherapy and radiation. Pain medicine and good mouth care can help.

• Diarrhea, nausea, and vomiting.  These may happen with chemotherapy, radiation, and GI irritation. Calories and protein may be given through an IV (intravenous) line until your child can eat again and the diarrhea has stopped.

• Fluid overload.  This most often occurs when the kidneys can’t keep up with the large amount of IV fluids being given. Your child will be watched closely for fluid overload. They will be weighed often, have blood tests, and their urine will be measured often. Medicines may be given to help kidney function and get rid of excess fluid.

• Breathing problems. Serious lung problems can be caused by infection, airway inflammation, fluid overload, graft-versus-host disease, and bleeding. Your child may need supplemental oxygen to breathe better until problems are treated.

• Organ damage. Short-term (temporary) or long-lasting (permanent) liver and heart damage may be caused by infection, graft-versus-host disease, chemotherapy and radiation, or fluid overload. Your child's blood and vital signs will be checked carefully to look for organ damage.

• Graft failure. The transplanted cells (graft) may fail to grow in the marrow. This may happen from infection, the disease coming back, or a stem cell count in the donated marrow that was too low. Graft failure may be treated with another bone marrow transplant.

• Graft-versus-host disease (GVHD). GVHD can be serious and life-threatening. It happens when the donor’s immune cells attack the recipient's healthy cells. Your child will be watched closely for GVHD. Signs can include diarrhea, fever, rash, skin changes, stomach pain, breathing problems, and decreased liver function. Your child will be given medicines before the transplant to reduce this risk.

How do I help my child get ready for a bone marrow transplant?

Before the transplant:

• The bone marrow transplant team will give your child an in-depth evaluation. The team will talk with you about the risks and benefits of transplant and other treatment choices.

• Your child will have physical exams and tests. The tests look at your child's blood. They check how well organs like the heart, kidney, liver, and lungs function.

• Your child may need to go to the transplant center up to 10 days before the transplant. A thin, flexible tube (catheter) called a central venous line is surgically placed in a vein in your child’s chest. Blood products and medicines will be given through the catheter.

The days before the transplant are counted as minus days. The day of transplant is considered day 0. Engraftment and recovery following the transplant are counted as plus days. For example, a child may enter the hospital on day -8 to prepare for the BMT. Days +1, +2, and so on, will follow the transplant. There are possible events, complications, and risks linked to each day before, during, and after transplant. The days are numbered to help you and your child know where you are in terms of risks and discharge planning.

What happens during a bone marrow transplant for a child?

Once suitable stem cells are found, your child will get high doses of chemotherapy or radiation (sometimes both) to destroy existing bone marrow. This gives the new bone marrow cells room to grow. This may be called ablative or myeloablative therapy. It stops new blood cells from being made. The bone marrow becomes empty. An empty marrow is needed to make room for the new stem cells to grow and create a new system to make new blood cells.

Next, stem cells are given to your child through an IV in a large vein, often in the chest. This is called a central venous catheter. Getting the stem cells is like having a blood transfusion. The stem cells find their way into the bone marrow. They start growing and making new, healthy blood cells.

During infusion of the bone marrow, your child may have:

• Pain

• Chills

• Fever

• Hives

• Chest pain

What happens after a bone marrow transplant for a child?

After infusion, your child may:

• Be at risk for infection

• Have some bleeding

• Have nausea, vomiting, diarrhea, mouth sores, and extreme weakness

• Have some emotional distress

Your child will get supportive care to prevent and treat infections, side effects, and physical and emotional complications.

During this time, your child may:

• Spend several weeks in the hospital

• Be confined to a very clean environment to reduce the chance of infection

• Take multiple antibiotics and other medicines

• Need blood transfusions

• Be given medicine to prevent GVHD

• Have daily blood tests

Engraftment of the stem cells happens when the donated cells make their way to the marrow and start making new blood cells. Engraftment usually happens between day +15 and +30. This depends on the type of transplant and the disease being treated. Blood tests will be done often to count blood cells after transplant. Platelets are usually the last type of blood cells to recover.

In some cases, engraftment can be delayed. This can be due to infection, medicines, low donated stem cell count, or graft failure. The new bone marrow may start making cells in the first 30 days after the transplant. But it may take months or years for your child’s immune system to fully recover.

The transplant team will tell you when your child is ready to go home. This depends on many things, such as:

• Extent of engraftment

• Complications

• Your child's overall health

• How far you live from the facility

Before you go home, you'll be instructed on ways to reduce your child’s risk of infection. These include:

• Special air filtered rooms

• Diet restrictions

• Limiting visitors

• Strict hygiene

• Frequent bed linen changes

Your child will then need to see the transplant team often to:

• See how well the treatment is working

• Look for signs of problems, such as infection

• Treat side effects, infection, and other problems

Long-term success varies from child to child. Emotional support for your child and family is vital during all phases of the transplant. Your transplant team will help you manage the stress of this process and offer support when your child returns home. They'll teach you about medicines, how to care for your child, and when and how to contact them with questions.

Your child’s transplant team will also talk with you about your child’s prognosis, follow-up care, and future treatments.

Next steps

Before you agree to the test or procedure for your child, make sure you know:

• The name of the test or procedure

• The reason your child is having the test or procedure

• What results to expect and what they mean

• The risks and benefits of the test or procedure

• When and where your child is to have the test or procedure

• Who will do the procedure and what that person’s qualifications are

• What would happen if your child didn't have the test or procedure

• Any alternative tests or procedures to think about

• When and how you'll get the results

• Who to call after the test or procedure if you have questions or your child has problems

• How much you'll have to pay for the test or procedure