Favorable outcome after withdrawal of immunosuppressant therapy in progressive multifocal leukoencephalopathy after renal transplantation: case report and literature review.

Progressive multifocal leukoencephalopathy (PML) is a fatal demyelinating disease caused by the JC polyomavirus (JCV). Most patients with PML after renal transplantation have had poor outcomes. We describe a patient with PML after renal transplantation who had a good response to the withdrawal of immunosuppressant therapy. We performed quantitative real-time PCR testing for JCV DNA in cerebrospinal fluid (CSF), and assessed mutation of the JC virus genome detected in the CSF. At the same time, we checked cranial magnetic resonance imaging (MRI). Immunosuppressant therapy was discontinued immediately. The MRI scan that followed showed markedly decreased numbers of high intensity signals, and the results of real-time PCR for JCV DNA in CSF became negative. The patient had no other neurological deficits. Withdrawal of immunosuppressant treatment has a beneficial effect on the course of PML after renal transplantation, and quantitative PCR may facilitate the immediate withdrawal of immunosuppressant agents.