Purpose of review: Discuss the recent evidence on cytomegalovirus (CMV) serology in allogeneic hematopoeic cell transplant (HCT) recipients.

Recent findings: Whereas the role CMV-specific cellular mediated immunity has recently emerged as an important factor of CMV DNAemia posttransplant, the value of CMV serology has remained unchanged through decades, associated with donor selection and posttransplant prophylactic and monitoring strategies. In this review, we describe and discuss the emerging reports on the association between the magnitude of pretransplant CMV immunoglobulin G (IgG) titer and the posttransplant incidence of CMV DNAemia, as CMV IgG titer could become an additional tool in CMV risk assessment in the future.

Summary: Pretransplant recipient CMV serology may have significant implications in posttransplant CMV reactivation in allogeneic HCT recipients.