Severe Bickerstaff Brainstem Encephalitis in a Young Adult Male: Delayed Recovery Despite Early Immunotherapy

Abstract

Bickerstaff brainstem encephalitis (BBE) is a rare post-infectious autoimmune disorder within the anti-GQ1b antibody spectrum, commonly presenting with ophthalmoplegia, ataxia, and impaired consciousness. Diagnosis is typically delayed because early symptoms are non-specific, and initial imaging often appears normal. We report a case of a 19-year-old male who initially presented with fever, limb weakness, and slurred speech. Within days, he deteriorated rapidly, requiring intubation. Initial imaging and cerebrospinal fluid analysis (CSF) were inconclusive. However, later serological studies revealed the presence of anti-GQ1b antibodies. Although MRI results were normal, the clinical picture was consistent with BBE. He underwent plasma exchange in the third week of illness. His recovery was complicated by hospital-acquired infection and barotrauma. His neurological recovery was slow. At the time plasma exchange was initiated (Day 21 of admission), the patient remained unresponsive with a Glasgow Coma Scale (GCS) of E1VTM1. By the sixth week of admission, his GCS had improved to E4V5M6, reflecting significant neurological recovery. With multidisciplinary rehabilitation, he eventually regained the ability to ambulate independently within 6 months. This case highlights the importance of considering BBE early in young patients presenting with acute brainstem dysfunction, even when initial imaging is unremarkable.