BK Virus nephropathy in living donor renal allograft recipients: An observational study from a large transplant center in India.

BK virus is a polyoma virus which remains in latent phase in the urinary tract, particularly in the renal tubular epithelial cells. In immunosuppressed patients, it is activated and manifests as tubule-interstitial nephritis causing renal allograft dysfunction. A total of 402 patients who underwent renal allograft biopsy from 2013 to 2016 were included in this study; six patients were diagnosed to have BK virus nephropathy. Histopathology showed ground glass intra-nuclear inclusions accompanied by acute tubular injury, interstitial inflammation, and varying degree of interstitial fibrosis and tubular atrophy. Patients were managed with reduction in the overall immunosuppression. Only one patient progressed to graft failure on follow-up. The overall prevalence of polyoma virus at our center is 1.49%.