Bone marrow is a soft, gelatinous tissue that resides in the centers of a person’s bones. When diseases such as leukemia, lymphoma, and sickle cell anemia inhibit the functionality of the bone marrow, a transplant of healthy marrow could be the best treatment option; for some patients, it is the only cure.
A bone marrow transplant is a surgical procedure necessary to replace a damaged bone marrow that has been affected by a disease, infection or in rare cases, chemotherapy. The actual process involves the relocation of stem cells, which are spread to the bone marrow. They are meant to help in the creation of new blood cells and encourage the growth of a new marrow.
Definition
The bone marrow is fatty tissue that is found inside the bones. It is significant since it creates a number of agents for the blood that is distributed throughout the human body. Red blood cells are cells which distribute oxygen and nutrients that are vital to all parts of the body. White blood cells are meant to combat disease whereas platelets are important for the formation of clots.
Furthermore, a bone marrow also consists of undeveloped blood cells, also known as hematopoietic stem cells (HSC). Most of these cells are not alike in nature and only exist for duplication.
More specifically, if these cells are damaged, then a bone marrow transplant may be administered. The surgery will introduce healthy blood cells and oust impaired ones. A transplantation will enable the patient’s body to function correctly again. For instance, the body will be able to produce sufficient red blood cells, white blood cells, and platelets if their bone marrow transplant is successful.
There are two ways of obtaining healthy stem cells. The first method is through a donor while the second includes acquiring them from within the patient’s own body. In the latter scenario, stem cells can be harvested if need be. For example, if the patient is suffering from cancer and is scheduled to undergo chemotherapy or radiation, then harvesting stem cells becomes mandatory.
Objective
Now that we understand what a bone marrow transplant involves, we can assess cases where the performance of a transplant may be necessary. Generally, a bone marrow transplant becomes mandatory when the existing marrow is unable to function adequately.
Reasons for a transplant include aplastic anemia. This is a disorder where the marrow no longer produces new blood cells. In addition, there are several types of cancers that can have an impact on the bone marrow too. Leukemia, lymphoma and multiple myeloma are relevant examples that make a transplant necessary.
Also, as we mentioned earlier, chemotherapy is also another possibility where a bone marrow transplant may be needed. There are cases where the bone marrow may erode since the body is in a weakened state during chemotherapy. The same rules apply to radiation as well.
Moreover, congenital neutropenia, a hereditary disorder in which the patient develops multiple illnesses, is another potential reason for a transplant to be conducted. So is sickle cell anemia, which is also inherited genetically and involves the presence of distorted red blood cells.
Finally, thalassemia is yet another case which may require bone marrow transplantation. When the body develops an abnormal form of hemoglobin, which is a vital component of healthy red blood cells, then that means the individual is suffering from thalassemia and needs surgery.
Types
Prior to surgery, a patient must undergo chemotherapy or radiation, depending on the requirement. This is determined by two distinct methods, the first of which is called Ablative (myeloablative) treatment.
This occurs when a high dosage of chemotherapy is administered. It is typically accompanied by radiation also. The treatment is done to eradicate the presence of cancerous cells in the body. A side effect of ablative treatment is that all the bone marrow that is healthy is also eliminated, which is why a transplant becomes mandatory once chemotherapy is completed.
The other method is called Reduced Intensity treatment (mini-transplant). In essence, this is the opposite of ablative treatment and the patient is exposed to lower doses of chemotherapy and radiation. This procedure is meant to cater to older individuals or patients whose bodies may not respond well to ablative treatment.
Additionally, there are also two basic classifications of bone marrow transplantation, which are stated as follows:
Autologous Bone Marrow Transplant
The transplanted stem cells originate from the body of a child who undergoes the procedure. Once the cells are obtained, surgeons store them safely. Then, these stem cells are inserted back into the affected child’s body when the destructive cells are removed through another procedure.
In case the child undergoes an autologous transplant, a donor is not required. Instead, the child’s own stem cells are used. They are exposed to bone marrow harvesting or stem cell mobilization before the actual transplant takes place.
The main advantage of using a child’s own stem cells is that they are no serious consequences such as graft versus host disease. This transpires when white blood cells are fighting against a child’s healthy cells. This happens because the cells may be donated by another person and do not agree with the child’s body.
Allogeneic Bone Marrow Transplant
Naturally, there are certain diseases which warrant stem cells to be used by a donor. This process is called an allogeneic transplant. This may prove to be a viable alternative for patients as well. Allow us to demonstrate why.
If the cells found inside the child’s body are considerably affected, then there is no likelihood that they may be replaced at a later stage. When the stem cells are beyond repair, an allogeneic transplant is a logical conclusion.
Likewise, stem cells which are donated may be more accustomed to eradicate the patient’s impacted cells. These are just some examples where undergoing an allogeneic transplantation can increase a child’s chances of being healthy in the long run.
However, the procedure is conditional. An allogeneic transplant is a riskier proposition in contrast to autologous transplants. This is because the cells of a donor and the recipient may not mix well at all, which can result in graft versus hold disease in the child. The feasible option in this instance is to locate a donor who is related to the child. For example, using stem cells from a parent or sibling can yield better results once the surgery is complete.