An engraftment syndrome in autologous stem cell transplantation related to mononuclear cell dose

Engraftment syndrome (ES) is a toxicity of autologous stem cell transplantation that occurs unexpectedly and is occasionally fatal. This syndrome, manifested as fever, rash and pulmonary deterioration which becomes evident at marrow engraftment, has been described by several centers but as yet remains enigmatic. We describe this syndrome at a single institution and note that it has accompanied the transition from the use of autologous marrow rescue to peripheral blood stem cell rescue. In this study, the occurrence of ES is related to the mononuclear cell dose at reinfusion. We found, in agreement with other reports, that patients developing ES are predominantly women undergoing therapy for solid tumors who demonstrate neutrophil engraftment at a significantly greater rate than do those patients not expressing the syndrome. We did not note a significant relationship between growth factor use (G-CSF) or amphotericin B exposure and the syndrome, as has been previously reported. The progenitor cell populations obtained with autologous marrow and peripheral blood stem cells are different. We hypothesize that the interaction of committed myeloid precursors from the stem cell product with the pulmonary vascular endothelium can be deleterious, especially under the influence of the inflammatory cytokines present at the time of engraftment.