An investigation of the utility of plasma Cytomegalovirus (CMV) microRNA detection to predict CMV DNAemia in allogeneic hematopoietic stem cell transplant recipients

Precise identification of patients at highest risk for developing Cytomegalovirus (CMV) DNAemia may improve CMV infection management in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) setting. Here, we studied the potential use of detecting free CMV micro(mi)RNAs circulating in plasma for predicting CMV DNAemia in this clinical scenario. A total of 62 adult allo-HSCT recipients were included in this prospective observational multicenter study. Plasma CMV DNA load was monitored using the CMV RealTime CMV PCR (Abbott Molecular, Des Plaines, IL, USA). Detection of mature CMV miRNAs in plasma drawn by days + 7, + 14 and + 30 after allo-HSCT was performed using the miScript PCR System (Qiagen, Hilden, Germany). Assays could be optimized for five out of the seven targeted CMV miRNAs: UL36-5p, US33-5p, UL148D, UL22A-5p and UL112-3p. Of the 62 patients included in the study, 42 developed a first episode of CMV DNAemia at a median of 35 days after allo-HSCT. All targeted CMV miRNA were detected early after transplantation, with CMV miRNA US33-5p and UL112-3p the most commonly found species at any time point; nevertheless, neither the detection rate of CMV miRNAs nor their abundance allowed discrimination between patients with subsequent CMV DNAemia and those with no CMV DNAemia. The data presented herein do not support any predictive utility of these CMV miRNAs for first episodes of CMV DNAemia in a cohort consisting primarily of allo-HSCT patients receiving haploidentical allografts.