Bone Marrow Transplant
It is also called a BMT, stem cell transplant, or hematopoietic stem cell transplant.
The centre of bones contains bone marrow, where blood cells are produced. It resides in the spongy portion of the bones, particularly the hips, ribs, breastbone, and vertebrae. Hematopoietic stem cells, the youngest form of blood cells, are found in bone marrow. A hematopoietic stem cell transforms into a white, red, or platelet as it matures. The bone marrow, peripheral blood (bloodstream), and umbilical cord blood all contain hematopoietic stem cells.
A bone marrow transplant (BMT) replaces diseased or damaged cells with noncancerous stem cells capable of generating healthy new cells. When cancer treatments have eradicated normal bone marrow stem cells, BMT is typically performed. Through BMT, stem cells can be replaced. Additionally, a BMT is conducted when the likelihood of being cured with chemotherapy alone is low.
Bone Marrow Transplant (BMT) Types
- Allogeneic: When bone marrow or blood cells are received from a donor other than the patient, an allogeneic transplant is performed. These can originate from a related donor, an unrelated donor, or the umbilical cord. This form of transplant is utilized for leukaemia and lymphoma patients.
- Autologous: An autologous transplant is carried out when the patient's own bone marrow or blood cells are used. Bone marrow or cells are collected, frozen, then reconstituted, and reinfused when necessary. Patients with solid tumours such as neuroblastoma, Hodgkin's disease, and brain tumours undergo this form of transplant.
Performing a Bone Marrow Transplant
Before the transplant admission:
When the healthcare team determines that BMT is the optimal treatment for your child, they will schedule an extensive discussion with you to explain the procedure. They will explain the numerous hazards associated with BMT and what to expect before, during, and after the transplant.
Your child will undergo testing to ensure they are healthy enough to endure the transplant procedure. Evaluations will include electrocardiogram (ECG) and echocardiogram of heart function, lung function (if your child is mature enough), kidney and liver function, and infection status. Depending on the disease, an aspiration of the bone marrow and a spinal tap may be conducted.
When physicians determine that your child is healthy enough for BMT, they will typically insert a central line catheter that provides simple access to a large vein in the chest. The catheter will deliver new stem cells, blood, antibiotics, and other medications during treatment.
Preparation Before Transplant:
- The eradication of malignancy
- Creating space in the bone marrow for the growth of new cells.
- Immune system suppression so that new cells can be accepted
The Transplant
After conditioning, stem cells are administered via the catheter. This closely resembles a blood transfusion. After travelling through the bloodstream to the bone marrow, the transplanted stem cells will initiate the production of red and white blood cells and platelets.
It can take between 14 and 30 days for the body to produce enough blood cells, mainly white blood cells, to combat infection. Engraftment refers to the identification of new blood cells and an increase in white blood cells following BMT. Your child will be at a high risk of infection, anaemia, and bleeding until then. Your infant will remain hospitalized until they are healthy enough to be released.
Advice for Parents
As infection risk and other complications persist following discharge, outpatient follow-up is mandatory. Even though the risk of relapse (cancer recurrence) is lower with a transplant than with chemotherapy, deterioration can still occur. The majority of relapses occur within a few years of a transplant.
Immediate, Frequent Side Effects
- Before, during, and after the transplant, infections are very prevalent.
- Anaemia (insufficient red blood cells) and thrombocytopenia (low platelets). There will be a need for transfusions of red blood cells and platelets until the new cells multiply sufficiently to produce them.
- Mucositis (sore pharynx and sore mouth). Intravenous (IV) nutrition and pain medication treat these symptoms. This issue typically improves as the patient's new cells multiply.
- Loss of appetite and vertigo are symptoms of anaemia. To prevent weight loss, nutrition is administered intravenously or through a catheter placed in the stomach. Some medications can be administered to avoid or reduce nausea.
Long-Term Dangers
- Infection - After a transplant, the patient's immune system is destroyed, and it can take months or even years to recover. There are three possible varieties of infections: bacterial, fungal, and viral. Certain patients are administered preventive antibiotics. After discharge, special measures are taken to protect your infant from disease, such as limiting visitors and avoiding crowded areas (such as stores).
- Graft-versus-host disease (GVHD) occurs only in allogeneic bone marrow or blood transplants. Certain varieties of donor cells, known as T cells (or T lymphocytes), recognize the patient's body as "foreign." Medications are administered post-transplant to prevent this complication but it may still occur.
1. Acute graft-versus-host disease typically occurs within three months of transplantation. The epidermis, liver, and intestines can be affected. Skin involvement appears as a red rash that may be irritating or develop blisters. Involvement of the liver may result in jaundice or an elevation of other liver tests. The involvement of the intestines may produce very severe, watery diarrhoea. Steroids are used to treat GVHD and are frequently effective at controlling the condition.
2. Chronic graft-versus-host disease - which can occur months or even years after a transplant - can occur. Typically, chronic GVHD is a continuation of acute GVHD. Many various body parts may be affected. The skin is the most commonly affected organ; patients may exhibit scarlet, scaly, or thickened skin. In addition, there may be alterations in the mouth's lining, dry eyes, joint stiffness, lung restriction, and difficulty assimilating nutrients from food. In addition, patients are at risk for infection due to the medications required to control GVHD and the immunosuppressive effects of GVHD.
- Toxicity to organs - Preparation and prior cancer treatment may cause harm to the lungs, liver, kidneys, and heart. These effects are unpredictable, and not all children with organ toxicity recover.
Late Effects - There is a high probability that BMT will result in long-term side effects that may only be identified years after treatment. These consist of:
- Growth and other endocrine (gland) issues may develop depending on the type of conditioning employed.
- Sterility is prevalent among the majority of patients.
- The liver, kidneys, lungs, and heart can sustain organ damage.
- Cataracts can develop, clouding the eye's lens and diminishing vision.
