Atypical Unilateral-Onset Guillain-Barré Syndrome Mimicking Acute Stroke: A Case Report.

Guillain-Barré syndrome (GBS) is an acute immune-mediated neuropathy that can present with a wide spectrum of neurological deficits, sometimes in atypical forms that complicate early diagnosis. Atypical presentations may mimic other neurological emergencies, contributing to diagnostic delays. We report the case of a 67-year-old man with a history of alcohol misuse who presented with sudden-onset unilateral lower-limb weakness initially suspected to represent an acute stroke. Over several days, his weakness progressed to involve both lower limbs, accompanied by sensory loss, gait ataxia, and diffuse areflexia. Cerebrospinal fluid (CSF) demonstrated albuminocytologic dissociation, and nerve conduction studies (NCS) confirmed a demyelinating polyneuropathy. The patient subsequently developed respiratory compromise requiring intensive care unit (ICU) monitoring and intubation. Intravenous immunoglobulin (IVIG) was initiated, resulting in gradual clinical improvement. This case highlights the importance of comprehensive neurological examination and maintaining a broad differential diagnosis when evaluating acute focal weakness, particularly when initial findings are incomplete or atypical.