Bickerstaff brainstem encephalitis

Bickerstaff brainstem encephalitis is a rare inflammatory disorder of the central nervous system, first described by Edwin Bickerstaff in 1951. It may also affect the peripheral nervous system and shares features with Miller Fisher syndrome and Guillain-Barre syndrome. Its exact cause remains unclear; the condition is believed to be autoimmune in nature, though this explanation does not fit every patient, and some cases appear to stem from infection or lymphoma, with researchers suspecting that more than one autoimmune mechanism can produce a similar clinical picture. Initial symptoms include drowsiness, gait disturbance and double vision. Most patients go on to develop loss of muscle coordination and paralysis of eye movement, along with altered consciousness ranging from drowsiness to coma, abnormal reflexes, facial weakness, and involuntary eye movements. Symptoms typically emerge within one to two days of onset.