How Bone Marrow Transplant Works — From Diagnosis to Recovery
Bone marrow transplant sounds like surgery. It is not, exactly. There is no incision, no operating theatre in the traditional sense, no stitches. The transplant itself — the day the stem cells are actually given — looks like a blood transfusion. It takes a few hours. The dramatic parts are what come before and after.
What the Transplant Is Actually Doing
Bone marrow produces blood cells. When bone marrow goes wrong — as it does in leukaemia, when it produces malignant cells that crowd out normal ones — the entire blood-producing system needs to be replaced.
The transplant does this in three stages. First, the existing marrow is destroyed. Then, healthy stem cells are introduced. Then, those stem cells establish themselves in the marrow cavities and begin producing normal blood cells again.
The body's existing immune system goes with the diseased marrow. During the gap — while the new stem cells are establishing — the patient has essentially no immune system. This is the most dangerous period.
Stage One — Conditioning (One to Two Weeks)
Before any stem cells are given, the existing marrow must be destroyed. This is done with high-dose chemotherapy, sometimes combined with total body irradiation (in some allogeneic transplant protocols).
The drugs used in conditioning are more intense than standard chemotherapy — doses that would be dangerously suppressive in a normal chemotherapy course are used deliberately here, because the goal is complete marrow ablation. The patient is in hospital throughout, in a dedicated BMT room with strict infection control: positive-pressure rooms, HEPA-filtered air, rigorous hand hygiene protocols for all staff and visitors.
During conditioning, the patient feels the effects of high-dose chemotherapy — nausea, mucositis (painful sores in the mouth and throat), fatigue. Modern antiemetics manage nausea significantly better than they did a decade ago. Mucositis is painful and managed with pain relief and careful oral hygiene.
By the end of conditioning, the blood counts drop to near zero. The patient cannot fight infection. They cannot clot blood adequately. They are transfusion-dependent.
Stage Two — The Transplant (Infusion Day)
The stem cells are given intravenously through a central line — a line placed in a large vein in the chest or neck. If the transplant is autologous (the patient's own previously collected and frozen stem cells), the bag of cells is thawed and infused. If allogeneic (from a donor), the freshly collected stem cells arrive from the collection team.
The infusion takes two to four hours. The patient may notice a smell — stem cells are preserved in a solution called DMSO, which has a distinctive garlic-like odour that comes out through the breath and skin. Beyond that, most patients experience relatively little during the infusion itself.
The stem cells enter the bloodstream and travel to the marrow cavities — a process called homing. They find the marrow space and begin establishing themselves there. This takes time.
Stage Three — Engraftment (Two to Four Weeks)
Engraftment is when the transplanted stem cells begin producing blood cells in meaningful numbers. Blood count monitoring — typically daily — tracks this. The count is essentially zero for the first week to ten days. Somewhere around day ten to fourteen, the neutrophil count begins rising. This is engraftment.
Until engraftment, the patient requires:
- Regular platelet transfusions (to prevent bleeding)
- Regular red blood cell transfusions (to prevent anaemia)
- Aggressive antibiotic and antifungal prophylaxis
- Strict isolation
Infections during this period are the main cause of early mortality after BMT. Bacteria, fungi, and viruses that a healthy immune system would handle without trouble can be life-threatening in a patient with no functioning immune defences. The BMT unit's protocols — room design, visitor restrictions, prophylactic drugs — all exist to minimise this risk.
For allogeneic transplants, graft-versus-host disease (GVHD) begins to appear around engraftment time. The donor immune system — now beginning to function — may recognise the recipient's body as foreign. Acute GVHD typically affects skin (rash), gut (diarrhoea), and liver (elevated enzymes). Most cases are managed with steroids. Severe acute GVHD is a serious complication.
After Engraftment — The Outpatient Phase
Once engraftment is confirmed and the patient is clinically stable — usually three to four weeks after the transplant — discharge from the BMT unit becomes possible. The patient transitions to outpatient follow-up.
This phase still requires frequent monitoring. Blood counts are checked several times per week initially. Tacrolimus or cyclosporine levels are monitored if the patient is on these for GVHD prevention. Liver function is tracked. Viral monitoring — particularly for CMV and EBV — is routine.
The immune system reconstitutes gradually over months. Full immune reconstitution after allogeneic transplant takes one to two years. During this time, infection risk remains elevated and some vaccines need to be repeated.
For autologous transplant, the immune reconstitution is faster — typically six to twelve months for reasonable immune function.
Total Time in India for BMT Patients
Given the conditioning period, the transplant itself, and the post-engraftment outpatient monitoring required before it is safe to fly home, most BMT patients from Africa need to plan for six to ten weeks in India. Families should arrange accommodation near the hospital for this duration from the start.
BMT Hospitals in Prime Medical's Network
Max Super Speciality Hospital, Saket, Delhi (JCI, NABH, NABL) — Dr. Rohit Nayyar manages cancer care and coordinates haematology and BMT cases. Dedicated BMT unit with isolation rooms. Both autologous and allogeneic transplant programmes. Haploidentical transplant available.
Indraprastha Apollo Hospital, New Delhi (JCI, NABH) — Full BMT programme. Paediatric BMT alongside adult transplant. Africa desk.
Fortis Memorial Research Institute, Gurugram (JCI, NABH, NABL) — Haematology and BMT programme. Strong infection management infrastructure critical for the engraftment phase.
For patients from Addis Ababa, Kampala, Dar es Salaam, Mwanza, Banjul, or Serekunda who have been told bone marrow transplant is needed: share haematology reports, bone marrow biopsy, and HLA typing with Prime Medical Solutions. Dr. Rohit Nayyar and the transplant teams review within 48 hours.
To book a consultation, call the number on our website.
