PML during dimethyl fumarate treatment of multiple sclerosis: How does lymphopenia matter?

Klaus Lehmann-Horn¹, Horst Penkert¹, Peter Grein¹+4

• ¹From the Department of Neurology, Klinikum rechts der Isar der Technischen Universität München (K.L.-H., H.P., B.H., A.B.); Munich Cluster for Systems Neurology (SyNergy) (K.L.-H., B.H.); Ilmtalklinik GmbH Pfaffenhofen (P.G.); Department of Neurology, Klinikum Ingolstadt (U.L.); and Institute of Neuropathology (S.T.-H.), University of Duisburg-Essen, Essen, Germany.+1