Rescue of severe brain and cervical cord IRIS by restarting natalizumab in a pregnant MS patient

Abstract

Natalizumab inhibits lymphocyte trafficking across the blood-brain barrier, reducing relapse rates by up to 70% in patients with relapsing-remitting multiple sclerosis (RRMS). Discontinuation of the drug, usually due to pregnancy or risk of progressive multifocal leukoencephalopathy (PML), can trigger the return of disease activity or, occasionally, a fulminant immune reconstitution inflammatory syndrome (IRIS) as lymphocytes re-enter the CNS. 1-3