Only a fraction of the millions of people worldwide with blood and autoimmune disorders survive - especially those in poorer countries - partly due to the lack of bone marrow stem cell transplants. A recently established Nigerian bone marrow registry hopes to boost matches between donors and patients, and survival chances.
Some 200,000 babies are born annually in sub-Saharan Africa with sickle cell disease, a blood disorder in which mutated red blood cells can clump and block blood vessels, causing pain, infection and organ damage. Nigeria has up to two million sickle cell patients, many of whom can benefit from stem cell transplants.
Stem cells are the building blocks of blood and immune cells. “Establishing the mechanics of stem cell transplantation in Nigeria is a very important milestone,” said Terry Schlaphoff, deputy director of South Africa’s bone marrow registry.
Bone marrow registries hold key information about stem cell donors to help match them with patients. There are currently two such registries in Africa, one in South Africa and now Nigeria.
In countries with low per capita incomes, stem cell transplants remain relatively rare due to lack of knowledge, trained health workers and, most importantly, availability of stem cells. “African patients who need a matching donor have virtually no chance of survival, unless they are wealthy enough to travel abroad for treatment,” said Seun Adebiyi, founder of Nigeria’s bone marrow registry.
Matching bone marrow or blood cells collected from donors to the patients who need it can offer lifesaving treatments for more than 70 diseases, including leukaemia, lymphoma (cancer) and sickle-cell anaemia.
Worldwide, there are fewer than 15 million registered donors, and patients far outstrip the number of donors, according to the Netherlands-based information centre, Bone Marrow Donors Worldwide (BMDW).
Reflecting only a fraction of overall need, 14,206 transplants from non-relatives and 4,255 transplants from umbilical cord blood were provided to patients worldwide in 2011, said Machteld Oudshoorn, chair of BMDW’s editorial board.
For most patients in developing countries, awaiting a transplant “remains associated with significant morbidity and mortality, and represents one example of high-cost, highly specialized medicine”, according to a recent medical report.
Adebiyi, himself diagnosed with stem cell leukaemia and lymphoblastic lymphoma, is also calling for the establishment of Nigeria’s first umbilical cord bank, as the cord can provide stem cells without having to collect them from donors, thereby increasing matches and reducing waiting times.
The more donors there are, the better the chances are of finding a match, said Schlaphoff. “It is said that the likelihood of finding a match is one in 100,000, but for some patients it may be one in a miracle. Because of …the need for very close matching [of cells], no country is self-reliant.”
Globally, it is already difficult to get a stem cell transplant from a non-relative, with only one-third of patients able to do so, said Oudshoorn. Nearly half of all stem cell transplants occur with cells originating outside the patient’s country of residence.
None of the some 50,000 transplants performed in 2006 were in countries with incomes below US$700 per capita, according to the most recent data compiled by BMDW and only 2 percent of bone marrow transplants took place in the Eastern Mediterranean and African regions combined. Most transplants took place in Europe (48 percent) and the Americas ( 36 percent).
Three countries in Africa are able to harvest and transplant bone marrow - Egypt, South Africa and Nigeria.
“I think it is very important to establish a national registry, but there should also be transplant centres experienced in performing transplantations with allogeneic [genetically different human] donors,” said Oudshoorn.