Delayed recovery of neutrophil counts after peripheral stem cell transplantation which improved with administration of a minimal dose of G-CSF: A case report

G-CSF administration may not affect the rate of engraftment unless sufficient numbers of stem cells are transplanted. However, there might be some cases in which neutrophil recovery is delayed after stem cell transplantation despite a relatively fast recovery of platelet counts and total while blood cell counts. This delayed engraftment might be observed in either autologous or allogeneic stem cell transplantation. Here we report four cases with delayed neutrophil engraftment which subsequently improved with administration of a minimal dose of G-CSF. As the response occurred on the day following G-CSF administration, a mobilization defect is suspected to be the mechanism of this delayed engraftment.