Exploring the Types of Bone Marrow Transplant: The Life-Saving Procedure

Exploring the Types of Bone Marrow Transplant: The Life-Saving Procedure

772 Views

In the face of a diagnosis where the only treatment option is a bone marrow transplant (BMT), it’s perfectly natural to feel a lot of emotions, like fear and anxiety. The unknown procedures and unfamiliar terms and questions about the cost of a bone marrow transplant add another layer of stress to an already challenging situation. This blog provides clear and concise information on different types of bone marrow transplants and a breakdown of the procedures involved, to help ease some stress.

The reason for bone transplants can be to treat a variety of health conditions, including certain types of leukaemia, lymphoma, and other blood-related disorders.

Types of Bone Marrow Transplants

The following are the main types of bone marrow transplants, based on the source of the stem cells used in the procedure:

1. Autologous Transplant

In an autologous transplant, the patient serves as both the donor and the recipient of the stem cells. The stem cells are collected from the patient’s own bone marrow or peripheral blood. This is collected before the patients are scheduled for chemotherapy or radiation therapy.

This transplant option is not always available and bone marrow transplant specialists advise the procedure only when healthy bone marrow is present in the patient. Nonetheless, the chances of graft-versus-host disease (where the donor cells attack the recipient’s tissues) are null in an autologous bone marrow transplant.

2. Allogeneic Transplant

In an allogeneic transplant, the patient receives stem cells from a compatible donor, who can be a sibling, an unrelated donor, or sometimes, even stem cells from the umbilical cord of a newborn.

The donor is typically matched based on human leukocyte antigen (HLA) compatibility, which is crucial to reducing the risk of graft-versus-host disease.

A syngenenic transplant is a type of allogenic bone marrow transplant where stem cells from an identical twin are used. Since identical twins share the same genetic makeup, there is no risk of graft-versus-host disease. While syngeneic transplants are less common due to the rarity of identical twin donors, they offer a unique advantage in terms of compatibility.

In terms of the cost of a bone marrow transplant, the procedures start at around Rs. 10 to 15 lakhs in India. Autologous transplants are cheaper than allogenic ones, with donor transplants from umbilical cords usually being the costliest. It will depend on the exact procedure, location, and hospital too.

No matter the type, the purpose of a bone marrow transplant is to treat damaged or diseased bone marrow affected by certain disorders and cancers. Let’s learn how the transplant procedure is carried out.

Bone Marrow Transplant Procedure

The bone marrow transplant process is complex and meticulous, involving several key steps:

1. Pre-Transplant Evaluation

  • The pre-transplant evaluation is a crucial phase in the BMT procedure. It is a collaborative effort involving various medical specialists, including haematologists, oncologists, transplant coordinators, and other healthcare professionals.
  • Before the transplant, bone marrow transplant specialists conduct comprehensive medical evaluation of the patient to assess their overall health and suitability for the bone marrow transplant procedure.
  • Compatibility testing is also conducted at this stage to identify a suitable donor for allogeneic transplants.

2. Stem Cell Collection

To collect blood and deliver medicine, a central venous catheter is put into the patient’s chest through a vein.

  • Autologous
    1. In an autologous transplant, the patient serves as both the donor and the recipient of the stem cells.
    2. Peripheral Blood Stem Cell Collection (PBSC): Stem cell collection typically involves a procedure called apheresis. Before apheresis, the patient may receive medications, known as mobilising agents, to stimulate the release of stem cells from the bone marrow into the bloodstream.

During apheresis, blood is drawn from the patient’s vein and circulated through a machine that separates and collects the stem cells. The remaining blood components are returned to the patient.

  • Bone Marrow Harvest: Doctors may choose to collect stem cells from your hip bones using a needle.
  1. The collected stem cells are then processed, tested, and stored for later infusion after the conditioning phase.
  • Allogenic

In an allogenic transplant, the donor undergoes a stem cell collection procedure, which can vary based on the source of the stem cells:

  1. Peripheral Blood Stem Cell Collection (PBSC): Most commonly used for allogeneic transplants, this involves the donor receiving mobilizing agents to stimulate stem cell release into the bloodstream. Apheresis is then performed to collect the stem cells.
  2. Bone Marrow Harvest: In some cases, especially if PBSC collection is not feasible, stem cells are directly harvested from the donor’s hip bones through a surgical procedure under anaesthesia.
  • Cord Blood Transplant: Cord blood, collected from the umbilical cord and placenta of a newborn, can be a source of stem cells. Cord blood units are stored in banks and can be used for transplantation when needed.

3. Conditioning

  • The conditioning phase, also known as the preparative regimen, involves the administration of high-dose chemotherapy, radiation therapy, or a combination of both to prepare the patient for the transplant.
  • The high-dose chemotherapy or radiation therapy is designed to eliminate the patient’s existing bone marrow cells, which may be diseased or damaged.
  • Conditioning regimens also serve to suppress the patient’s immune system. This is crucial to prevent rejection of the transplanted cells, especially in allogeneic transplants.
  • The conditioning phase typically takes place in the days or weeks leading up to the actual bone marrow transplant.
  • It is a challenging phase for patients as it often comes with side effects such as nausea, fatigue, hair loss, and an increased risk of infection due to a weakened immune system.

4. Transplantation

In the transplantation stage, the stem cells that have been collected and processed are infused into the patient’s bloodstream to replace the damaged or diseased bone marrow.

The goal is for these transplanted stem cells to migrate to the bone marrow and initiate the process of engraftment, where they establish themselves and start producing new blood cells.

A central venous catheter (CVC) is often used to facilitate the infusion. The CVC is a long, flexible tube that is inserted into a large vein, usually in the chest, to allow for the smooth flow of stem cells into the bloodstream.

The process is gradual and may take several hours, ensuring a controlled and well-tolerated infusion.

Throughout the stem cell infusion, the patient is closely monitored for any adverse reactions or immediate side effects. Common side effects during this phase are generally mild and include symptoms like chills or fever.

5. Engraftment

Following the stem cell infusion, the patient enters the engraftment phase. Engraftment is the process in which the transplanted stem cells migrate to the bone marrow and start to produce new blood cells.

The time it takes for engraftment to occur can vary, but it generally takes several weeks. During this period, the patient may experience low blood cell counts, making them susceptible to infections and other complications.

Recovery

The recovery phase involves the gradual rebuilding of the immune system. Bone marrow transplant specialists monitor patients for signs of immune function, and immunosuppressive medications may be adjusted as needed.

Patients are often advised to follow strict infection control measures, including avoiding crowded places and practicing good hygiene, to minimise the risk of infections.

Maintaining adequate nutrition is crucial during the recovery phase. Nutritionists may work with patients to address dietary needs and manage any nutritional deficiencies.

Physical and occupational therapy may be recommended to help patients regain strength, mobility, and functionality. These therapies can address muscle weakness, fatigue, and other physical challenges that may have resulted from the transplant process.

Final Words

It’s important to note that the recovery phase after a bone marrow transplant is a dynamic process, and the medical team closely tailors the approach based on the patient’s specific needs and progress. Regular communication with the healthcare team, adherence to prescribed medications, and a commitment to self-care are crucial. As a lifesaving procedure, a bone marrow transplant can help improve the quality of life of individuals battling a number of conditions.

Disclaimer:

This article has been written for information purposes only, and is not a substitute for professional medical advice by a qualified doctor or other health care professional. The author is not responsible or liable, directly or indirectly, for any form of damages whatsoever resulting from the use (or misuse) of information contained in or implied by the information in this article. Always consult a qualified healthcare provider for accurate diagnosis, personalised treatment, and recommendations tailored to your individual health needs.

Share