A stem cell transplant is a strong treatment, and while it can be very successful at treating cancer and blood conditions, it can have many side effects and risks. Most patients will not have all of the side effects that are possible with stem cell transplant. Most of these side effects go away with time, but some may not go away. It's important to be aware of these risks and discuss them with your child's physician before treatment and after, should any symptoms arise.
The radiation doses and chemotherapy drugs used depend on the reason for the transplant, the type of stem cell donor and the child's condition. Some side effects are common to radiation therapy and all of the chemotherapy drugs used for transplant.
The patient's bone marrow and immune system is partially or totally destroyed by the chemotherapy and radiation therapy. The donor's stem cells can't make enough new blood cells to meet the body's needs until one to four weeks after transplant. As a result, patients have low numbers of white blood cells (to fight infection), red blood cells (to carry oxygen), and platelets (to help prevent bleeding). This puts patients at high risk for infection and bleeding.
Medicines are given to prevent infections. Usually, infections can be successfully treated, but they can be very serious. Severe bleeding can usually be prevented by giving platelet transfusions. If the donor's stem cells don't grow, the blood counts can be low for a long time. This can happen because of rejection of the stem cells, infection or damaged stem cells; however, this is very unusual. Giving more stem cells may help the blood counts recover. Radiation and most high-dose chemotherapy cause temporary hair loss, loss of appetite, nausea and vomiting, diarrhea and mouth sores.
The combination of radiation and high doses of chemotherapy can cause damage to the liver, lungs and kidneys. Severe damage is usually avoided by using doses of radiation and chemotherapy that have been shown to be well-tolerated by many patients and by making sure that the patient's organs are working well before transplant.
It is important to take good care of the mouth to prevent infections because high-dose chemotherapy and radiation therapy may lead to mouth sores. Patients are also encouraged to remain active during the early transplant period.
Physical therapists and child life specialists will help patients with activity. Getting up from bed helps expand the lungs and prevent lung infections. Being active helps prevent muscles from getting weak. Weak muscles can be a problem when patients are ready to go home after four to six weeks in the hospital. Therefore, we encourage patients to be out of bed as often as possible. Patients should also take a bath or shower daily to keep the skin clean.
Patients undergoing transplantation from another person are at risk for graft-versus-host disease (GVHD).
GVHD occurs when the donor's immune system cells see the patient's body as different from itself and attacks the patient's body. This is similar to when a part of our body has an infection and the immune system attacks the infected part of the body. Drugs will be given to prevent GVHD.
Acute GVHD generally occurs one to four weeks after transplant. Acute GVHD can cause a rash, diarrhea, and liver problems (jaundice). Chronic GVHD usually occurs more than 100 days after transplant. Chronic GVHD can affect the same parts of the body, but can also affect the mouth, eyes and lungs.
Chronic GVHD can weaken the immune system and increase the risk of infection. Many medicines are available to prevent and treat GVHD. Patients often take at least one of these medicines for several months after the transplant and sometimes for years if GVHD occurs.
Patients receiving a stem cell transplant will usually have a weak immune system for three to 12 months. This period may be longer if your child has graft-versus-host disease. A weak immune system can lead to infections. Usually, these infections occur as a result of growth of germs that are already in the body but that do not cause a problem when the immune system is normal. Patients that have had a stem cell transplant are kept out of school until their immune system recovers.
When in the hospital for transplant, the patient stays in a blood and marrow transplant room with an air filter that reduces fungal spores in the air. Fungal infection can cause serious infection after transplant, especially when the white blood cell count is very low. Patients are started on antibiotics and antifungal drugs to prevent infections. Many patients are also started on anti-viral drugs to prevent viral infections.
Viruses that cause colds in patients with normal immune systems can cause life-threatening pneumonia in stem cell transplant patients. For this reason, the transplant team will discuss with you how to avoid these viral infections. The most important things are good hand washing and avoiding people that are sick.
Although the patient may have received immunizations ("baby shots") before transplant, the chemotherapy and radiation therapy will often get rid of the protection given by these shots. These immunizations need to be given again after transplant. Immunizations are usually not started until at least one year after transplant.
Patients are on a special diet when their white blood cell count is low. The diet is intended to decrease the chance of getting bacterial and fungal infections.
It is common for patients to lose their appetite and for foods to not have much taste for a few weeks after transplant. If the patient is unable to eat enough, nutrition can be given through the central venous catheter.