Viral Load Kinetics: A Way to Assess Cumulative Effects of Cytomegalovirus on Hematopoietic Stem Cell Transplant Recipients

(See the Major Article by Stern et al, on pages 620–31.) Cytomegalovirus (CMV) has been associated with significant morbidity in hematopoietic stem cell transplant (HSCT) recipients, both via direct effects (DNAemia, end organ disease) and indirect effects (increased risks for other viral and/or fungal infections, graft-vs-host disease [GVHD]) [1, 2]. Predicting its impact on overall survival and nonrelapse mortality post-HSCT has been the focus of many studies. However, understanding cumulative morbidity associated with infections is difficult, as time to first event analyses do not account for recurrent events, and estimates can be biased without controlling for death [3]. Moreover, CMV DNAemia remains a risk factor for overall and non-relapse-related mortality despite institution of a preemptive therapy approach [1]. In this issue of The Journal of Infectious Diseases, Stern et al report a study of CMV outcomes in a large single-center...