A Bone Marrow Transplant, also known as a Hematopoietic Stem Cell Transplant (HSCT), is a medical procedure that involves replacing damaged or diseased bone marrow with healthy stem cells. These stem cells can come from the patient themselves (autologous transplant) or a compatible donor (allogeneic transplant).

The primary goal of a Bone Marrow Transplant is to treat various conditions like certain types of cancer (leukemia, lymphoma, multiple myeloma), severe aplastic anemia, and genetic disorders that affect the production of blood cells.

The procedure involves three main stages: a. Conditioning: High-dose chemotherapy, radiation, or a combination of both is administered to destroy the diseased marrow and suppress the immune system to prevent rejection. b. Transplantation: Healthy stem cells are infused into the patient's bloodstream, where they migrate to the bone marrow and start producing new blood cells. c. Engraftment: It is the phase where the transplanted stem cells begin to grow and produce healthy blood cells.

There are three main types of Bone Marrow Transplants: a. Autologous Transplant: The patient receives their previously collected and stored stem cells. b. Allogeneic Transplant: Stem cells come from a healthy donor whose tissue type closely matches the patient's. c. Syngeneic Transplant: The stem cells come from an identical twin of the patient.

Human leukocyte antigen (HLA) testing is performed to determine the compatibility between the patient and potential donors. The more closely the HLA markers match, the better the chance of a successful transplant.