Searches for matched and closely matched related and unrelated bone marrow donors undertaken in a single paediatric...

Information regarding the likelihood of finding suitable marrow donors is limited. In order to determine this potential, all patients who received their primary care at a single paediatric institution over a 9 year period and in whom tissue typing studies were initiated are reviewed. Forty-five (31.3%) of 144 patients had a sibling who was human leucocyte antigen (HLA) identical. A further 16 (11.2%) patients had immediate or more distant relatives who were either HLA identical (2.7%) or matched for five of six HLA antigens (8.3%). The possibility that a parent was closely matched with the patient was suggestive from the typing of siblings alone in only half the cases. Unrelated HLA matched donors were identified in four (27%) of 17 bone marrow bank searches. Overall, a potential related donor was identified within the family for 42% of patients and this figure rose to 45% when successful marrow bank searches were included. It can be concluded that initial typing should include both the parents and siblings. If a suitable donor is not found then an extended family and/or bone marrow bank search will identify additional suitable donors in a significant number of families.