Beneficial effect of plasmapheresis but not on IVIG in Bickerstaff's brainstem encephalitis

Four weeks after a severe pneumonia of unknown etiology, a 71 year-old woman developed progressive diplopia, gait ataxia and slurred speech over two days. Neurological examination revealed almost complete ophthalmoplegia, limb ataxia, severe dysarthria to anarthria, central tetraparesis mainly affecting the right hemiside with right sided extensor plantar response and drowsiness. Nerve conduction studies of the limbs including F-wave responses were normal. CSF analysis demonstrated a slight lymphocytic pleocytosis of 8/µl and was otherwise normal. Routine blood tests, anti-hu, anti-ri were negative. Anti-GQ1b Ig…