Progressive bilateral facial weakness

To cite: Carswell C, Northey LC, Davies L, et al. Pract Neurol 2015;15:76–79. A 72-year-old man presented with sudden onset of right-sided facial muscle weakness and slurred speech and a 3-day history of fevers, myalgia and sore throat. There was no hyperacusis, change in taste or lacrimation. His history included untreated hepatitis C diagnosed 10 years before, but quiescent at his annual liver review 8 weeks before presentation. He smoked cannabis intermittently but there was no recent alcohol or other drug abuse. There was a history of promiscuity with female partners. On examination, he was alert and orientated. His blood pressure was elevated at 159/86 mm Hg but other vital signs and general examination were normal. Neurological examination showed a severe right-sided lower motor facial weakness with Bell’s phenomenon (see online supplementary video). The remaining cranial nerve examination was normal, including eye movements, pupillary responses, facial sensation, hearing, taste and otoscopy. There was mild left hip flexion weakness but preserved deep tendon reflexes. There was reduced sensation to temperature in a glove-and-stocking pattern; joint-position sense, light touch and pain sensation were intact. There was mild gait instability on walking tandem. His condition progressed rapidly and on day 2 of admission he developed left-sided facial weakness (figure 1) with bilateral, proximal lower limb weakness. His paraesthesias were more painful. His lower limb deep tendon reflexes were no longer present (see online supplementary video). Spirometry remained normal. He was transferred to a high dependency unit for ongoing monitoring. Question 1