Pre-Engraftment Syndrome after Double-Unit Cord Blood Transplantation: A Distinct Syndrome not Associated with Acute Graft-Versus-Host Disease

Pre-engraftment syndrome (PES) occurring after cord blood transplantation (CBT) is poorly characterized. We reviewed 52 consecutive double-unit CBT recipients treated for high-risk hematologic malignancies. PES was defined as unexplained fever >38.3 °C (101°F) not associated with infection and unresponsive to antimicrobials, and/or unexplained rash occurring before or at neutrophil recovery. CBT recipients (median age, 38 years; range, 3-66 years) received either myeloablative (MA; n = 36) or nonmyeloablative (NMA; n = 16) conditioning. Sixteen patients (31%) fulfilled PES criteria: 15 with fever (median at onset, 39 °C [102.2°F]), 13 of whom also had rash, and 1 with rash alone. The median onset was 9 days (range, 5-12 days) posttransplantation (a median of 14 days before neutrophil recovery). Sixteen patients (14 with PES and 2 with infection and possible PES) received intravenous methylprednisolone (median dose, 1 mg/kg; median duration, 3 days); 15 (94%) experienced resolution of fever within 24 hours. Recurrent PES (n = 3) resolved with retreatment. There was no association between the development of PES and the likelihood of sustained donor engraftment, speed of neutrophil recovery, grade II-IV acute graft-versus-host disease (aGVHD), day-180 treatment-related mortality (TRM), or survival. PES is common after CBT, precedes neutrophil recovery, is distinct from and does not predict for aGVHD, and responds promptly to short-course corticosteroid therapy.