BKV VIRURIA AND VIREMIA DO NOT PREDICT HOSPITALIZATION FOR INFECTIONS AFTER KIDNEY TRANSPLANTATION

Abstract

BK polyoma virus (BKV) infection after kidney transplantation, resulting from either reactivation of latent infection in the recipient or transmission through the donor kidney, is understood to be related to the intensity of immunosuppression. Infections after transplantation being a function of immunosuppression burden in general, we hypothesized that early BKV viruria and viremia could indicate the likelihood of individuals needing hospitalization for all infections. We conducted a retrospective study among living donor renal transplant recipients in a program without the routine use of induction immunosuppressive agents, to explore the association between BKV viruria at two months post transplantation and viremia, with hospitalisation for any infection. The electronic case records of all patients who underwent renal transplantation between 8/5/2016 (start of the program) to 31-10- 2019 at IQRAA hospital Kerala, were reviewed to collect data on BKV viruria, viremia and hospitalisation for infections. A total of 149 patients had undergone transplantation during the study period of which nine were excluded from analysis (four patients within two months of transplantation, three patients with non-functioning graft within two months, one death within two months and one patient lost to follow up). 48 patients (34.28%) were detected urine BKV positive by polymerase chain reaction (PCR) around two months after transplantation, 74 patients tested negative and no data were available in 18. 24 out of the 48 patients with viruria had documented viremia by PCR. Among the rest 16 had no viremia, while data were missing in eight. Of the 122 patients with urine BKV data available 100 were ABO compatible (ABOc) transplants and the rest ABO incompatible (ABOi). 39 patients out of the 122 patients (31.96%) with urine BKV data available required hospitalization for infection. The median time to first hospitalization for infection was 139 days The most common causes for first hospital admission with infection after transplantation included lower respiratory tract infection and urinary tract infection/graft pyelonephritis in seven patients each, followed by Cytomegalovirus infection in five. No significant association was documented for hospitalization with infection either for BKV Viruria (χ2 (1, N = 122) =0.28, p = 0.59) or BKV viremia(χ2 (1, N = 58) =0.41, p = 0.51). ABOi transplantation was also not found to be significantly associated with BKV viruria (χ2 (1, N = 122) =0.09, p = 0.75). In this retrospective single centre study of living donor recipients BKV viruria at two months post renal transplant and BKV viremia were not found to be associated with hospitalization for any infection. Viral load cut offs to define severity of infection were not used and could have led to the inclusion of patients with lesser degree of immunosuppression confounding the results.