[Application of multiplex PCR assay to study early multiple herpesviruses infection during HSCT]

Objective: To investigate herpesvirus infection in early stage of hematopoietic stem cell transplantation (HSCT) by multiplex polymerase chain reaction (PCR), and to explore the association between multiple herpesviruses infection and clinical characteristics in HSCT patients and its impact on post-transplant complications and prognosis. Methods: A total of 734 peripheral blood samples were collected from 90 patients undergoing HSCT in the Department of Hematology, the First Affiliated Hospital of Soochow University between February 2017 and August 2017. The peripheral blood specimens were obtained before and within 90 days after transplantation at different time points. Lab-Aid824 Nucleic Acid Extraction Mini Reagent was used to extract DNA and multiplex PCR assay was used to simultaneously detect 8 kinds of human herpesviruses from genomic DNA. The incidence of various herpesvirus infections, its correlation with clinical features and effects on post-transplant complications and prognosis were analyzed. Results: The median follow-up time was 192 (range: 35-308) days. Among the 90 patients before transplantation, the incidence of herpes virus infection was 35.6% (32/90), including 12.2% (11/90) with one herpes virus infection and 23.3% (21/90) with multiple viruses infection. The incidence of herpes virus infection after transplantation was 77.8% (70/90), including 20.0% (18/90) with one herpes virus infection and 57.8% (52/90) with multiple herpes virus infection. Among the 52 patients with multiple herpes viruses infection, 30 (57.7%) patients were infected by 2 kinds of viruses, 18 (34.6%) patients by 3 kinds of viruses and 4 (7.7%) patients by 4 kinds of viruses. There was a correlation between HHV-6 and HHV-7 herpesvirus infection (OR=13.880, Q=0.026). EBV infection was related to HHV-7 infection (OR=0.093, Q=0.044). The age of patients was correlated with the incidence of HHV-1 infection before transplantation. There were 24 patients in our study experienced clinical symptoms associated with viral infection. The main manifestations were hemorrhagic cystitis (HC), interstitial pneumonia, enteritis, viral encephalitis and fever of unknown origin. EBV infection was related to HLA incompatibility and the inconsistent of the ABO blood group and grade Ⅱ-Ⅳ aGVHD after transplantation. HLA incompatibility and the unrelated donor and grade Ⅱ-Ⅳ aGVHD were related to multiple viruses infection. Conclusion: Multiple herpesviruses were common in patients undergoing HSCT, which were closely related to HLA mismatch, unrelated donor and grade Ⅱ-Ⅳ aGVHD.