Clinical outcomes of allogeneic hematopoietic stem cell transplant recipients developing Cytomegalovirus DNAemia prior to engraftment

There is limited information on the impact of CMV DNAemia episodes developing prior to engraftment (pre-CMV DNAemia) on clinical outcomes following allogeneic hematopoietic stem cell transplantation (allo-HSCT). This issue was addressed in the current retrospective multicenter study including 878 patients. All participant centers used preemptive antiviral therapy strategies for prevention of CMV disease. CMV DNA load in blood was monitored by real-time PCR assays. A total of 144 patients (cumulative incidence 16.5%, 95% CI, 14%-19%) had an episode of pre-CMV DNAemia at a median of 10 days after allo-HSCT. Patients who developed pre-CMV DNAemia had a significantly higher (P = < 0.001) probability of recurrent episodes (50%) than those who experienced post-CMV DNAemia (32.9%); Nevertheless, the incidence of CMV disease was comparable (P = 0.52). Cumulative incidences of overall mortality (OM) and non-relapse mortality (NRM) at 1-year after allo-HSCT were 32% (95% CI, 29-35%) and 23% (95% CI 20-26%), respectively. The risk of OM and NRM in adjusted models appeared comparable in patients developing a single episode of CMV DNAemia, regardless of whether it occurred before or after engraftment, in patients with pre- and post-engraftment CMV DNAemia episodes or in those without CMV DNAemia.