Bone Marrow Transplantation

Related Subjects: |Herpes Varicella-Zoster (Shingles) Infection |Chickenpox Varicella Infection |Varicella Cerebral Vasculopathy |Herpes Viruses |Herpes Zoster Ophthalmicus (HZO) Shingles |MonkeyPox |Mumps |Measles |Rubella (German Measles) |Epstein-Barr Virus infection | Cytomegalovirus (CMV) infections | CMV retinitis infections | Toxoplasmosis

Related Subjects: | Oncological emergencies

About

• Haematopoietic stem cell transplantation
• BMT works on the principles of destroying and replacing existing bone marrow cells

Mechanism

• Replaced with stem cells or bone marrow from a donor or from self
• This can be done using chemotherapy and/or radiotherapy (MYELOABLATION).
• Myeloablation e.g. Cyclophosphamide with busulfan or total body irradiation is used
• There is induced bone marrow failure.
• The patient has then infused donor bone marrow stem cells which populates the now vacant marrow.
• After 3-4 weeks the new haemopoietic cells begin to produce red cells, platelets, and granulocytes
• There is a high risk of opportunistic infections

Allogeneic BMT

• Uses HLA matched donor - from a related HLA identical donor or a volunteer unrelated donor
• Donors cells are collected from their bone marrow and infused into the recipient.
• The chance of a match from a sibling is 1 in 4.

Autologous BMT

• Re infusing the patient's own bone marrow stem cells after ablation of the marrow
• Has the added bonus of no GVHD.
• Stem cells are harvested from peripheral blood after G-CSF or GM-CSF

Syngeneic BMT

• Using an identical twin

Autologous BMT

• Alternatively in children stored umbilical cord blood is obtained when parents elect to harvest and store the blood from a newborn's umbilical cord and placenta after birth. Cord blood has a higher concentration of Haemopoietic Stem Cells than is normally found in adult blood.

Complications

• Severe neutropenia with acute infection is the most worrying development.
• Graft versus host disease can be useful in haematological disease as the donor cells attack the remaining tumour cells. In fact, infusion of T cells from the donor can boost the response. This is called donor lymphocyte infusion (DLI)
• The overall mortality from the procedure is 30% and it is usually restricted to those under the age of 45.
• Other significant complications include CMV infection and acute and chronic GVHD.
• Supportive care is needed for several weeks until the new marrow engrafts.
• Patients develop mucositis, gastroenteritis and may need parenteral feeding.

Some Conditions for which BMT is contemplated

• ALL, AML
• Paroxysmal nocturnal haemoglobinuria
• Sickle-cell disease
• Myelodysplastic syndrome
• Neuroblastoma
• lymphoma
• Ewing's Sarcoma
• Desmoplastic small round cell tumour
• Hodgkin's disease
• Multiple myeloma