BK Virus Viremia in the First Days After Bone Marrow Transplantation: A Case-Control Study

Background: Reactivation of BK virus (BKV), viremia is a major clinical complication in transplant recipients. There are many studies of BKV infection among tissue transplant recipients, especially renal-transplant recipients. Although the presence of BKV in patients’ urine occurs frequently, the detection of BKV in the blood of transplant recipients, especially after bone marrow transplantation (BMT), is less studied. Objectives: The aim of this study was to detect BKV in 54 blood samples of BMT recipients in the first days after transplantation. Methods: This case-control study was performed in a university-affiliated hospital, Tehran, Iran, from October 2017 to October 2018. Blood samples were collected from 54 hematopoietic stem cell transplant recipients, and 54 healthy subjects without any tissue transplantation, and tested daily for BKV DNA using the quantitative real-time PCR technique. Results: In this study, two patients (3.7%) developed BK viremia at a median of 10 days (range: 1 - 10 days) after BMT, while none of the control subjects was positive for BKV in blood samples. The analysis of data showed no significant difference between the case and control groups (CI: 0.986 - 1.094, P < 0.153). Conclusions: Our data suggest that BKV viremia involved in active infection may not occur in the first days after BMT. This finding can affect controlling and managing BMT patients.