Bone marrow donation is a medical procedure that provides healthy blood-forming cells, known as stem cells, to patients suffering from various life-threatening diseases. These conditions often include blood cancers like leukemia and lymphoma, as well as other blood disorders such as sickle cell anemia. Donated stem cells help replace unhealthy cells in a patient’s body, offering a chance for recovery and improved health. The process of finding a compatible donor involves matching human leukocyte antigens (HLA), which are proteins on cells that the immune system uses for recognition.
Understanding Donation Methods
There are two primary methods for collecting stem cells for transplantation: bone marrow donation and peripheral blood stem cell (PBSC) donation. Bone marrow donation involves a surgical procedure where marrow is collected from the donor’s pelvic bone. This is performed under anesthesia, ensuring the donor does not feel pain. The collection typically takes one to two hours, and donors usually go home the same day or after an overnight stay.
PBSC donation, which accounts for the majority of stem cell donations, is a non-surgical outpatient procedure similar to donating plasma or platelets. Before donation, donors receive filgrastim injections to increase stem cells released into the bloodstream. During the donation, blood is drawn from one arm, passed through a machine that separates the stem cells, and the remaining blood is returned to the donor through the other arm. This apheresis process typically lasts four to eight hours and may require one or two sessions.
Criteria for Repeat Donation
It is possible to donate bone marrow more than once, as the body constantly renews its blood-forming cells. However, the decision to request a second donation depends on several factors, including the donor’s health, the type of previous donation, and the specific needs of a new recipient. Donor registries, such as Be The Match, manage these criteria to ensure donor safety and efficacy.
For PBSC donations, the body typically replaces the donated stem cells within approximately four to six weeks. A second PBSC donation might be considered if the transplanted cells have not engrafted in the patient, if the patient experiences a relapse, or if an additional boost of stem cells is needed to help restore the patient’s immune system. Some registries limit donations, often to twice for either PBSC or bone marrow collections, to minimize donor strain. A longer interval, such as 12 months or more, is beneficial for optimizing stem cell yields.
Repeat bone marrow donations are also possible, but they are less common than repeat PBSC donations. Similar to PBSC, the body naturally replenishes the donated marrow within a few weeks. Eligibility for subsequent donations is determined by factors like the donor’s age, overall health status, and the outcomes of the previous donation. Medical professionals ensure that any repeat donation does not compromise the donor’s health, with typical minimum intervals between six to twelve months for recovery and reassessment.
Safety and Recovery for Repeat Donors
The well-being of donors is a primary concern, and strict medical guidelines are followed for both initial and repeat donations. For bone marrow donation, the most common side effects include back or hip pain, fatigue, and mild nausea, which typically resolve within a week. The median recovery time for full recovery after a bone marrow donation is about 20 days. The main risk associated with bone marrow donation is related to the anesthesia used during the surgical procedure.
PBSC donors may experience flu-like symptoms, such as bone or muscle aches, headaches, and fatigue, due to the filgrastim injections received before the collection. These side effects are generally mild and disappear shortly after the donation is complete. The median time to full recovery for PBSC donation is approximately one week. Studies suggest that donor experiences for second donations are similar to those of the first. Thorough health screenings and continuous medical monitoring are in place to safeguard the health of individuals who donate multiple times, ensuring that any potential risks are carefully weighed against the benefits for the recipient.