Schwab, Dale A.

AbstractWe present a case of JC polyomavirus (JCV)‐associated nephropathy (PyVAN) in an asymptomatic deceased‐donor kidney transplant recipient. Despite the presence of viral cytopathic effect in the kidney biopsy and positive BK polyomavirus (BKV) in situ hybridization (ISH), BKV real‐time polymerase chain reaction (PCR) results of plasma and urine were negative. JCV ISH was performed and was found to be positive. JCV real‐time PCR on urine, plasma, and the kidney biopsy tissue was positive. Reduction in immunosuppression resulted in resolution of JCV viremia. This case highlights that JC‐PyVAN is a distinct clinical entity and is likely to have a better clinical outcome than BK‐PyVAN. Concurrent infection with BKV and JCV may occur, but may be difficult to confirm due to the potential for cross‐reactivity between BKV and JCV ISH stains.