Unknown cytomegalovirus serostatus in primary immunodeficiency disorders: A new category of transplant recipients.

We identify a novel group of recipients, R(x), with an intermediate level of survival and CMV incidence post-HSCT, when compared to seropositive and seronegative recipients. No evidence of CMV transmission from D(+) in R(-) and R(x) was observed. We believe R(x) should be considered as a separate category in future studies to better delineate recipient risk status.