Kidney Allograft Dysfunction Due to John Cunningham (JC) Virus Nephropathy.

John Cunningham (JC) polyomavirus-associated nephropathy (JC-PVAN) is a rare cause of polyomavirus-associated nephropathy (PVAN). Although BK polyomavirus (BKPyV) is a relatively proven common infection post kidney transplantation, JC polyomavirus (JCPyV) infection and its impact on graft function have been less studied. Here, we report a case of a deceased donor kidney transplant recipient who was diagnosed with allograft dysfunction due to JC-PVAN six years after transplantation. JC viremia resolved after a reduction in immunosuppression and treatment with intravenous immunoglobulin (IVIG); however, she developed an acute cellular rejection with moderate fibrosis resulting in chronic kidney disease in the allograft.