# Bickerstaff Brainstem Encephalitis Presenting With Negative Anti-GM1 and Anti-GQ1B Antibodies

## TL;DR

A rare case of Bickerstaff Brainstem Encephalitis is described, highlighting the importance of clinical diagnosis despite negative antibody tests.

## Contribution

This case emphasizes the clinical diagnosis of Bickerstaff Brainstem Encephalitis even when antibody tests are negative.

## Key findings

- The patient's symptoms aligned with Bickerstaff Brainstem Encephalitis despite negative anti-GM1 and anti-GQ1b antibodies.
- The case highlights the need for a systematic approach in diagnosing rapid-onset neurological symptoms.
- Treatment included ventilatory support, immunoglobulins, and steroids.

## Abstract

A woman in her 60s initially presented with rapid-onset left-sided hemiparesis with later development of slurred speech and left-sided facial droop. Despite ruling out common causes, her condition rapidly progressed with the development of bilateral proximal weakness, ophthalmoplegia, ataxia, and pyramidal signs eventually leading to a cardiorespiratory arrest. Extensive investigations, including computerised tomography (CT), magnetic resonance imaging (MRI), and lumbar puncture (LP), were negative for infectious or vascular aetiologies. Nerve conduction studies (NCS) revealed severe peripheral nerve damage, and despite a provisional diagnosis of Guillain-Barré Syndrome (GBS), the clinical picture aligned more with Bickerstaff Brainstem Encephalitis (BBE) given the central nervous system (CNS) involvement, despite negative anti-GM1 and anti-GQ1b autoantibodies. Treatment involved ventilatory support, immunoglobulins, and steroids. This case report describes a rare and challenging presentation of BBE and reminds clinicians to have a systematic approach to a patient presenting with rapid onset neurological symptoms and that BBE is a clinical diagnosis.