1. ¹Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
2. ²Department of Hematology, Leiden University Medical Center, Leiden, The Netherlands

Correspondence: Dr JS Kalpoe, Department of Medical Microbiology, E4-68, Leiden University Medical Center, PO Box 9600, Albinudreef 2, Leiden 2300 RC, The Netherlands. E-mail: J.S.Kalpoe@lumc.nl

³These authors contributed equally to this paper.

Received 24 November 2006; Revised 23 March 2007; Accepted 30 March 2007; Published online 28 May 2007.

Abstract

Reports on infectious complications following reduced intensity conditioning (RIC) before allogeneic stem cell transplantation (allo-SCT) are equivocal. This prospective follow-up study compared the impact of cytomegalovirus (CMV) infections following RIC with fludarabine, ATG and busulphan or conventional myeloablative conditioning (MAC). Forty-eight RIC and 59 MAC patients were enrolled. The occurrence and severity of CMV infections within 100 days following allo-SCT were assessed, using plasma CMV DNA load kinetics. CMV DNAemia was observed in 21 RIC (60%) and in 19 MAC (44%) patients at risk for CMV. The mean CMV DNAemia free survival time was comparable following RIC and MAC: 70 days (95% (confidence interval) CI: 59–80 days) and 77 days (95% CI: 68–86 days), respectively (P=0.24). Parameters indicative for the level of CMV reactivation, including the area under the curve of CMV DNA load over time as well as the onset, the peak values and duration of CMV infection episodes, the numbers and duration of CMV treatment episodes and recurrent infections, were not different in both groups. During follow-up, none of the patients developed CMV disease. RIC with fludarabine, ATG and busulphan demonstrated safety comparable to conventional MAC with regard to frequency and severity of CMV infections within 100 days following T cell-depleted allo-SCT.