What is an Allogeneic Bone Marrow Transplant?

Bone marrow is the spongy substance in the bone which contains stem cells. The stem cells develop into mature blood cells including red and white cells along with platelets. Various diseases can damage the bone marrow. When this occurs, a bone marrow transplant may be needed. An allogeneic bone marrow transplant is one type of transplant which uses bone marrow from a donor.

Two other types of transplants include a transplant using stem cells and an autologous transplant, which uses a patient’s own bone marrow. The type of transplant suggested may depends on the disease being treated. An allogeneic bone marrow transplant is often recommended over other types of transplants to treat cancers such as leukemia.

The process for an allogeneic bone marrow transplant can be tough on the patient. Preparation includes high doses of chemotherapy and radiation to kill the patient’s own marrow. Side effects from the chemotherapy may occur and can include fatigue, decreased ability to fight infection, vomiting and muscle aches.

Prior to a patient preparing for an allogeneic transplant, a bone marrow donor must be found. Donors must have a compatible tissue type and certain proteins found in the tissue. This compatibility reduces the chance a patient will reject the marrow. A bone marrow match is usually found through family members, community donor drives or through the National Marrow Donor Program in the United States.

After a transplant physicians test for signs of engraftment. This means that the donor bone marrow is growing and new blood cells are being made. Various blood tests are performed daily to check for engraftment. Although it may vary, according to the National Donor Marrow Program, engraftment is common 20 days after transplant.

Side effects and complications after a patient receives an allogeneic bone marrow transplant may occur, including infections, which can be severe. Late term complications can include damage to the heart or lungs and infertility. Because the marrow is from a donor, it’s possible the patient will reject the marrow. When this occurs a condition called graft versus host disease(GVHD)may develop, which can be acute or chronic. Graft versus host disease can develop anytime after a transplant. The condition is considered acute if it develops within the first 100 days after transplant or chronic if it occurs after this time period.

Symptoms of GVHD include a skin rash, which can become severe. Gastrointestinal symptoms can also develop and include vomiting and diarrhea. GVHD can be mild to severe, and in some situations becomes life-threatening.