Acute demyelinating disease after interferon β-1a treatment for multiple sclerosis

Recombinant human interferon (INFβ) benefits both relapsing-remitting and secondary progressive MS.1,2⇓ INFβ usually is well tolerated; the most common side effects are transient, flu-like symptoms and injection site reactions.3 We report a case of quadriplegia and brain stem disease probably related to an acute demyelinating process after the first injection of INFβ-1a. A 21-year-old man with relapsing-remitting MS was referred for paraplegia and weakness. When MS was first diagnosed in July 1998, he presented with paresthesia and weakness of the left upper extremity, and he was successfully treated with IV methylprednisolone. Cerebral MRI showed small demyelinating lesions of the white matter (figure, A through C), and CSF analysis detected oligoclonal bands of IgG. A few months later, he presented with the same symptoms and again responded to IV methylprednisolone. One month later, INFβ-1a was initiated …