What is Allogeneic Bone Marrow Transplant?
An allogeneic bone marrow transplant uses healthy blood cells from another person to displace damaged or diseased bone marrow in the body. It is also called allogeneic stem cell transplant. The donor of the stem cell can be anyone whose blood cells are well suited for transplant even if the donor is unacquainted. These blood stem cells can be taken from a donor’s blood, blood from a donated umbilical cord or hipbone of the donor through the bone marrow.
Bone marrow is a fatty and soft tissue within the bones which produces blood cells. There are immature cells inside bone marrow which elevate the number of blood cells often known as stem cells.
Allogeneic bone marrow transplant process types
Before treatment, radiation and chemotherapy can be conducted. It is done in two ways namely: reduced-intensity treatment and myeloablative treatment.
- Reduced-intensity treatment: it is also known as mini transplant. It is required generally in old aged people or people with other health disorders. It employs a low dose of radiation and chemotherapy before bone marrow transplant to make it safe in such patients. But it is not suitable in patients with rapidly spreading cancer or in case of several cancers.
- Myeloablative treatment: it is also known as an ablative treatment. In this procedure, an adequate dose of radiation and chemotherapy is used to destroy cancerous cells. Though it destroys healthy blood cells, it does not hinder the growth of new blood stem cells inside the bone marrow.
What is Allogeneic Bone Marrow Transplantation procedure?
The transplant is normally completed by releasing stem cells through bloodstreams. This is done using a venous catheter which enables the cells to travel into the bone marrow. Extraction of healthy stem cells is done in two ways that are leukapheresis and bone marrow harvest.
In leukapheresis, a donor is injected for a few days to transfer stem cells into the blood from bone marrow and is extracted from a donor using a tube. After this, red blood cells are deposited back in the donor’s blood while stem cells, found in white blood cells, are separated through a device and preserved for further use. On the other hand, minor surgery is done after administering anaesthesia in case of bone marrow harvest. During the procedure, the donor is asleep while stem cells are extracted from hip bones. The amount of bone marrow depends on the receiver’s weight.
What is the preparation before Allogeneic Bone Marrow Transplant?
All necessary medical checkups are done before transplant like MRI, CT scan, x-ray and ultrasound. After this almost two tubes that are central venous catheters are guided in the blood vessels of arms or neck. Through this tube nutrition, fluids and medications are received while blood is drawn out. After a transplant, the patient is kept under medical attention for checking the count of blood and other symptoms of recovery. Overnight stay is not required in most conditions before treatment but after it, hospital stay depends on the transplant type, development of side effects or complications and discharge procedure of a hospital. Often drugs are given to avoid GVHD and for treating infections. These medicines are antiviral, antifungal and antibiotics. The patient can undergo several blood transfusions. Direct intake of diet is not possible due to mouth soreness and stomach complications thus a thin tube is used for supplying nutrients directly into the body.
Importance of allogeneic bone marrow transplantation
This transplant uses white blood cells which attack infection causing virus and bacteria. It is an important method for treating several non-cancerous and cancerous diseases such as multiple myeloma, haemoglobinopathies, Hodgkin’s lymphoma, aplastic anaemia, mild leukaemia, neuroblastoma, congenital disorders of metabolism, severe leukaemia, bone marrow failure, deficiencies of the immune system, Adrenoleukodystrophy, Non-Hodgkin’s lymphoma, primary amyloidosis, disorders of plasma cells, POEMS syndrome and myelodysplastic syndrome.
Recovery from transplant
Recovery takes weeks before a patient can return to work. Healthy lifestyle, light exercises and balanced diet should be followed to recover faster. For diet, eggs should be well cooked before eating, milk, yoghurt and cheese must be pasteurized, pasteurized juices, fruits and vegetables must be washed properly and raw sprouts must be avoided. Raw honey and cream-filled sweets are prohibited. Heavy straining activities and weightlifting are also prohibited.
Allogeneic bone marrow transplant risks
Some complications involved in allogeneic stem cell transplant are menopause, retarded growth of children, cataracts, pain, vomiting, nausea, diarrhoea, damaged functioning of lungs, liver, heart and kidney, severe infections, anaemia, blood clotting in the veins of the liver, bleeding from the brain, intestine and lungs, mucositis that is soreness and inflammation of mouth, oesophagus, throat and stomach and graft versus host disease. However, these side effects depend on the type of transplant, suitability of cells of the donor, previous health condition and age.
Allogeneic bone marrow transplant benefits
It is a safe procedure overall as only the best-suited blood cell is used which highly reduces chances of any complications. It is most successful with approximately 62% of survival rate. It is a quick and efficient method. It shows faster results with reduced symptoms of the disorder and it is suitable for all age groups. Another important benefit is those normal stem blood cells create their immune cells and eventually replace all cells with new healthy cells. These cells are efficient in destroying those cancer cells that are left during high radiation treatment. Allogeneic bone marrow transplant treats many diseases like leukaemia, aplastic anaemia etc. easily and used for curing several other diseases.
Allogeneic vs. autologous bone marrow transplant
The main difference between autologous and allogeneic bone marrow transplant is the donor of blood cells. In autologous bone marrow transplant, blood stem cells are extracted from the patient itself for replacing damaged ones. In this case, the rate of survival is approximately 85%. It is considered more reliable because in allogeneic bone marrow transplant sometimes new cells attack normal cells along with diseased cells which require another treatment procedure. This misjudging is not seen in autologous transplant as it is from the same body. However, it is not free from some complications and these are side effects due to high dose of cancer removing treatment, infection, hepatic veno-occlusive disease and rare complication involving the failure of the graft. Another advantage is that the patient is getting its blood cells back into his body.
Syngeneic bone marrow transplant
Syngeneic BMT is a specific type of allogeneic bone marrow transplant and it is applicable only in case of an identical sibling of a patient. The reason is this transplant requires identical tissue for a patient. Its advantages include no risk of graft versus host disease and no chance of cancer in newly transplanted blood stem cells as it is more prevalent in autologous bone marrow transplant. A disadvantage is no graft versus cancer effect because of the identical or similar immune system. So efforts to remove all cancer cells are necessary for preventing the return of cancer.
What is the cost of allogeneic bone marrow transplant?
Cost of allogeneic bone marrow treatment ranges from $100,000 to $350,000. This cost differs according to hospital facilities and visits. It is an expensive treatment which is covered by medical insurance companies.
Is allogeneic bone marrow transplant painful?
No, allogeneic bone marrow transplant is not painful. If you experience any pain or discomfort, during the procedure, inform it. However, slight discomfort is normal. This transplant is generally conducted under anaesthesia which makes it painless.
How to prepare for allogeneic bone marrow transplant?
Before transplant, get all the medical checkups done, stop all previous medicines, inform the doctor about the health condition, get someone to look for hospital formalities, do not eat anything for 10-12 hours before treatment and take prescribed diet until transplant.
What are the side effects of allogeneic bone marrow transplant?
Common side effects are chest pain, fever, low blood pressure, lack of breath, foul taste of mouth, headache, nausea, chills, pain, hives and flushing. Most of these symptoms vanish over time and in case of severity consult a doctor immediately.
How much time does allogeneic bone marrow transplant take?
It takes almost one or one and a half hours for transplant. Preparation, primary tests and radiation or chemotherapy can take several more hours. 5-6 days can be spent in hospital under doctor’s observation.