Based on the results of the Preliminary Search, the patientโs physician will decide whether toย activate the search.
An active search has the following phases:
Preliminary Search
Initially, there is a preliminary search to identify a suitable donor for a patient i.e. a volunteer adult or a cord blood unit with the closest HLA (tissue type) match. By international convention, there is no charge for a preliminary search. Potential donors are identified using the local database and the international database of World Marrow Donor Association (WMDA) Search and Match Service (WSMS), and at this stage the match is โon paperโ.
Note: WSMS is an organization that catalogues the tissue types of the > 40 million volunteers, world-wide. The South African Bone Marrow Registry is a participant in this initiative.
For more information about the procedure and cost, please contact the SABMR Accounts Department.
Activation of The Search
If the search is urgent, and many are, it is customary to test more than one donor at a time.
Donor Selection
The first choice, whenever possible, is a donor from the SABMR (local) database. However, this is not always possible because of the extreme variability of the HLA system. Many patients do not find a potential donor in their โhomeโ registry and it will then be necessary to turn to the international database immediately. Currently, 45% of stem cell donations worldwide cross international borders.
Donor testing strategy
Extended typing of selected donor/s
Ideally, a donor should have information at all of the HLA loci (points of matching). Some donors are listed who have incomplete information. Such a donor might still be the best potential match for a patient and the transplant centre will then request that extended typing of the donor takes place. The results will be reported to the transplant centre. The patient / funder will be required to pre-pay / provide authorisation for the costs involved.
If the donor is not a match after further testing, another donor โ if more are available โ is selected and the process begins again.
If the search is urgent, and many are, it is customary to test more than one donor at a time.
Confirmation typing of potential donor/s
When the donorโs HLA typing indicates that there is a potential match with the patient, the next step is to obtain a fresh sample from the donor for mandatory confirmatory typing. This HLA typing must ideally take place in the same laboratory that performed the HLA typing of the patient. The SABMR further requires that this testing takes place in an internationally accredited laboratory. At present, the only such laboratory in South Africa is the NHLS Laboratory for Tissue Immunology, Cape Town, which is accredited by the European Federation for Immunogenetics.
If the search is urgent, and many are, it is customary to test more than one donor at a time.
Procurement of stem cells
Postponement / Cancellationย Fees
If the procurement of stem cells is postponed or cancelled prior to collection (or shipment in the case of a cord blood unit), a postponement or cancellation fee will be charged to recover the costs for tests and other activities already performed.