Demyelination during anti-TNFα therapy for ankylosing spondylitis.

A 34-year-old ankylosing spondylitis (AS) patient on etanercept for 30 months presented to neurologists with paresthesia of his hands and feet. Magnetic resonance imaging (MRI) scans showed multifocal hyperintense lesions. Symptoms did not improve on stopping the anti-tumor necrosis factor (TNF) agent. Few cases of demyelinating disease occurring after more than 2 years of treatment with anti-TNF agents have been reported in patients with AS. Opthalmologists, internists, neurologists, and rheumatologists need to be aware of these adverse events, as patients may present to any of these specialties many years after treatment.