Monitoring cytomegalovirus infection by antigenemia assay and two distinct plasma real-time PCR methods after hematopoietic stem cell transplantation

Abstract

We compared a CMV virus load determined by real-time PCR with an antigenemia value to analyze the correlation between these two methods. We also compared the values for virus load determined by the two distinct real-time PCR methods, which amplify the US17 region and immediate-early (IE) gene of CMV, respectively, to evaluate the reliability of these methods. Two hundred and sixty-five samples were obtained weekly from 29 patients, who had engraftment after unrelated bone marrow transplantation or HLA-mismatched related blood stem cell transplantation. CMV infection was detected in 115 samples from 22 patients by US17-PCR and 69 samples from 20 patients by the antigenemia assay. Fifty-eight samples were positive for both assays, but 57 and 11 samples were positive only for US17-PCR and antigenemia, respectively. A good correlation of the results of US17-PCR and antigenemia was demonstrated (r = 0.61). All antigenemia-positive samples and randomly selected antigenemia-negative samples were subjected to IE-PCR. The results of IE-PCR showed a good correlation with those of antigenemia (r = 0.64). Furthermore, the best correlation was observed between US17-PCR and IE-PCR (r = 0.83). In conclusion, both real-time PCR methods showed a good correlation with the antigenemia assay, and could be used to monitor CMV infection after hematopoietic stem cell transplantation.