Case report of multiple sclerosis diagnosis in an 82-year old male.

An 82-year old male, with no significant past medical history, presented with a subacute right foot drop in the setting of a 14-month history of generalised weakness, highly-responsive to steroids. Temporal artery and vastus lateralis biopsies were normal. Vasculitic screen and inflammatory markers were normal. Lumbar puncture revealed elevated cerebrospinal fluid (CSF) protein without oligoclonal bands. Visual evoked response (VER) was normal. Magnetic resonance imaging (MRI) of his lumbar spine showed compression of exiting L5 nerve root. He had three cerebral MRI scans spaced over the 12 month period, which showed a progressive increase of T2 and fluid attenuated inversion recovery (FLAIR) hyperintense lesions consistent with active demyelinating plaques. He was treated with intravenous methylprednisolone 1g daily for three days with a weaning regimen of oral prednisolone, resulting in a full return of power and a resolution of his right foot drop. He was diagnosed with late-onset multiple sclerosis (LOMS), and was treated with monthly natalizumab. A literature review of LOMS is discussed.