An Insight into Bone Marrow Transplantation
Authored by Dr.Pawan Kumar Singh Introduction
What is bone marrow? Bone marrow is the soft, spongy fatty tissues present inside the cavities of bones. It is the principal source for all the red blood cells, platelets and most of the white blood cells. Blood cells are formed in the marrow of flat bones. The main flat bones from where blood cells are formed are shoulder blades, ribs, breastbone and the pelvis. All the blood cells are derived from a single type of cell called the stem cell (haemopoietic cells or blood forming cells). The body’s hormones control production of stem cells as per individual’s body requirement. What is Bone Marrow Transplant? A bone marrow transplant or haemopoietic stem cell transplant is a procedure of replacing the affected bone marrow with healthy bone marrow stem cells of donor or of patient itself. There are 3 sources of stem cells viz. directly from bone marrow (BM), mobilized Peripheral Blood Stem Cells (PBSC) or from Umbilical Cord Blood (UCB). From bone marrow these cells are
extracted under general anesthesia. All the sources of stem cells are almost negligible risk to the donor. After giving conditioning chemotherapy to the recipient these stem cells are infused just like blood transfusion.
When is the bone marrow transplant needed? Bone marrow transplants are usually chosen to treat the conditions in which the blood cells are not functioning properly or they are replaced by defective cells such as in cancer. Following are the several conditions which may damage the bone marrow and may need bone marrow transplantation to treat the condition. Common conditions are: • Bone marrow failure • Cancer of WBCs (leukemia) • Cancer of lymph nodes and system • Sickle cell anemia • Thalassemia • Immune system disorders • Certain solid cancers What are the different types of bone marrow transplant available? There are two different types of bone marrow transplants available today. These are as follows: • Rescue transplant (Autologous bone marrow transplant): This procedure enable patients to receive high dose chemotherapy, but patients cannot produce their own blood cells because of such high dose. So before giving such chemotherapy patient’s stem cells are extracted and cryopreserved at -80 degree and then re infused. Allogeneic transplant: This procedure involves extracting the stem cells from healthy donor (which fulfills all the criteria’s of matching with the patient and the safety profile) and then infused it into the patient’s body. Donor’s cells continuously fight against the evolving recipient’s cancer cells. How much time does the bone marrow transplantation procedure take? You may have to be admitted in the hospital much before the planned transplantation so that doctors can give you the pre-transplant treatment (conditioning). The duration required for the whole procedure may vary from patient to patient. Usually, it takes one to two days to complete the transplantation after the conditioning of four to ten days. And then normal formation (engraftment) of donor’s cell takes 10 -20 days depending on the source of stem cells (7-10 days in PBSC and 14-20 days in BM or UCB) •
What to expect? Before the transplant: • You may be examined to ensure that this procedure will be safe and productive for you. • The examination of your health condition may continue for days, that include: o Physical assessments o Laboratory analysis including blood exams (esp. screening for viral infections) o X-rays, CT scans and MRI o Bone marrow biopsy (removing a sample of bone marrow and examining it) • As a preparative regimen, one may have to undergo conditioning, which involves chemo therapy and radiation therapy to reduce defected bone marrow and cancerous cells.
Conditioning also helps to create a space for new bone marrow. • The procedure of collecting stem cells from bone marrow will be done under anesthesia. • Collecting stem cells to be transplanted: o Healthy stem cells will be extracted from the donor to be transplanted. o Procedure collecting stem cells from peripheral blood is done by machine after giving 4-5 days of growth factors into the skin. These may cause some body ache or headache. This whole procedure may take about 3-5 hours and this may be repeated until the desired number of stem cells are collected and frozen to preserve. During the transplant: • A catheter is inserted into a vein right above the heart, to a place the medication and other material inside and extract blood samples. • The catheter will be used to transplant the stem cells into the blood which ultimately gets settled in the bone marrow and replace unhealthy cells. After the transplant • The patient may be discharged after the engraftment and if all the health parameters are normal. • A test may be conducted to see if the newly transplanted cells are working appropriately. • Medication will be given and you may have to take dose of certain medicines on a daily basis regularly as per the doctor’s advice. • The patient may be given IV fluids before and after the procedure to make body susceptible to preservatives (frozen stem cells). • The patient may not be allowed to resume any full-time work or daily schedule at least for six months after the transplant. • The patient may have to visit the doctor for regular examination every week for 3-6 months after the procedure •
What are the side effects/risks of the blood marrow transplantation? After the bone marrow is transplanted, there may be possible side effects, such as: • Nausea • Vomiting • Graft versus Host Disease (GVHD) • Infertility • Bacterial, viral or fungal infection • Fatigue • Mouth ulcer • Diarrhea • Anemia • Excessive hair fall • Sudden change in the skin color • Rashes • Eye defects like cataract • Disturbed sexual life
Pneumonia • Liver damage • Hypertension The donor may experience following side effects: • Stiffness in the area from where the bone marrow is taken out • Donor may not be able to resume daily routine for 2- 3 days • In case of some abnormality or infection, the donor may have to stay back at home for up to four weeks to regain strength. • Body ache, headache in case of PBSC donor. When to see a doctor immediately? It is important to contact the doctor immediately if the following side effects are seen: • Raised body temperature with chills and sore throat • Problem while urination • Excessive thirst • Yellowing, rashes or paling of skin color and eyes • Unusual bleeding What is the required care to be taken after the bone marrow transplant? Extra care may be required as recommended below: • Follow the recommended diet and exercise plan • Practice good personal and external hygiene • Avoid tobacco consumption • Avoid exposure to infectious atmosphere or people • Avoid going to public places and use face mask to prevent infections • Protect yourself from common illnesses • Drink enough fluids • Avoid drinking unpasteurized milk, other dairy products and fruit juices • Avoid eating raw meat, sea foods, salads, raw grains, cheese, sprouts like beans etc. • Take all the medicines regularly as per the doctor’s advice •