Preemptive antiviral therapy relies on viral load measurements and is the mainstay of cytomegalovirus (CMV) prevention in hematopoietic cell transplant (HCT) recipients. However, optimal CMV levels for the initiation of preemptive therapy have not been defined.The objectives of our work were to evaluate the relationship between plasma CMV DNA levels at initiation of preemptive therapy with time to resolution of viremia and duration of treatment.Retrospective analysis of HCT recipients undergoing serial CMV PCR testing between June 2011 and June 2014 was performed.221 HCT recipients underwent preemptive therapy for 305 episodes of CMV viremia. Median time to resolution was shorter when treatment was initiated at lower CMV levels (15 days at 135-440 international units (IU)/mL, 18 days at 441-1000IU/mL, and 21 days at >1000IU/mL, P<.001). Prolonged viremia lasting >30 days occurred less frequently when treatment was initiated at 135-440IU/mL compared to 441-1000IU/mL and >1000IU/mL (1%, 15%, 24%, P<.001). Median treatment duration was also shorter in the lower viral load groups (28, 34, 37 days, P<.001).Initiation of preemptive therapy at low CMV levels was associated with shorter episodes of viremia and courses of antiviral therapy. These data support the utility of initiating preemptive CMV therapy at viral loads as low as 135IU/mL in HCT recipients.
View details for DOI 10.1016/j.jcv.2015.06.006
View details for Web of Science ID 000358318400037