Leukocyte transfusions revisited: stem cell graft stimulation in graft failure

The aim was to evaluate the role of leukocyte transfusions (LTX) in relation to graft function during prolonged neutropenia after stem cell transplantation (SCT).

In 1989-2005, 22 SCT patients have received LTX in our unit. In all patients severe infection with profound neutropenia (<0.2 x 10(9)/L) preceded LTX. 13/22 had multi-organ failure or thrombotic microangiopathy. Irradiated leukocytes from pooled random donor products at 1.0 x 10(10) leukocytes/m(2)/day for a minimum of 3 days were used. Myeloid recovery and clinical benefit were analyzed.

Engraftment defined as an absolute neutrophil count (ANC) of >0.5 x 10(9)/L on three consecutive days was observed in 15/22 (68%) patients at median of 6 (range 2-25) days after LTX, and sustained engraftment (ANC of >0.5 x 10(9)/L for 4 weeks) in 11/22 (50%) patients. Clinical benefit was observed in 6/22 (27%) patients with a prolonged antecedent neutropenia, who still demonstrated rapid sustained engraftment after LTX. Ongoing thrombotic microangiopathy was associated with persistent graft failure.

LTX from random donors was associated with a rapid recovery of myeloid function in severely ill SCT patients. We speculate that allostimulation by LTX may have a role.