Early identification of patients at risk of death due to infections, hemorrhage, or graft failure after allogeneic bone marrow transplantation on the basis of the leukocyte counts

Allograft recipients are often unwell with significant organ dysfunction by the time delayed or failed engraftment is diagnosed. We attempted to identify factors associated with graft failure, or death due to infection, hemorrhage or graft failure in 712 patients undergoing allogeneic BMT. Low leukocyte counts between days 12 and 22 were strongly associated with subsequent graft failure or death. In multivariate analysis, a leukocyte count of ≤ 0.2 x 10⁹/l on day 16 was the most powerful predictor of graft failure or death. Transplants from HLA-mismatched and unrelated donors were also associated with increased risk of both, and T cell depletion with increased risk of graft failure. On the basis of these findings, it may be possible to define graft failure in functional terms as early as 2 weeks after BMT rather than at 3 or 4 weeks. The use of growth factors can then be limited to patients most likely to benefit from them, and it may be possible to salvage patients at risk of complications of low counts early before their clinical condition deteriorates. We suggest that patients with leukocyte counts of 0.2 x 10⁹/l or less 14-16 days after BMT should be started on GCSF or GM-CSF even if they are clinically well, and consideration should be given to a second infusion of cells.