Ganciclovir-related neutropenia after preemptive therapy for cytomegalovirus infection: comparison between cord blood and bone marrow transplantation.

We studied ganciclovir (GCV)-related neutropenia after preemptive therapy for cytomegalovirus infection: 9 of 17 (53%) cord blood transplantation (CBT) patients and 18 of 20 (90%) bone marrow transplantation (BMT) patients developed GCV-related neutropenia with an absolute neutrophil count (ANC) of less than 1,000/microl. Among the patients who did not receive granulocyte colony-stimulating factor, 2 (13%) and 1 (7%) CBT patients, and 10 (56%) and 8 (44%) BMT patients, developed neutropenia with an ANC of less than 500 and 250/microl, respectively. The incidences of neutropenia in patients with an ANC of less than 1,000, 500, and 250/microl were significantly lower after CBT in comparison with BMT. Two BMT patients, but no CBT patients, developed neutropenic fever, and both patients recovered after antibiotic therapy. In CBT patients, a creatinine clearance rate of less than 50 ml/min and an absence of steroid therapy were associated with a greater incidence of GCV-related neutropenia. No risk factors for GCV-related neutropenia were found in BMT patients. These results suggest that GCV may be less toxic to myeloid progenitor cells from cord blood than those from bone marrow.