PML during dimethyl fumarate treatment of multiple sclerosis: How does lymphopenia matter?
Abstract:
Progressive multifocal leukoencephalopathy (PML), which is caused by the John Cunningham virus (JCV), is a rare brain disease that results in persistent neurologic disability or death. In multiple sclerosis (MS), PML is a major concern in patients treated with natalizumab, and treatment duration (more than 2 years), preceding immunosuppression, and JCV antibody serostatus are identified risk factors, which are used for risk stratification, patient monitoring, and counseling.