Miller Fisher Syndrome Overlapping Pharyngeal-Cervical-Brachial Variant Guillain-Barré Syndrome: A Case Report with Triple Ganglioside Antibody Profile

Abstract Background: Miller Fisher syndrome and pharyngeal-cervical-brachial variant are distinct Guillain-Barré syndrome entities with characteristic ganglioside antibody associations. Overlap syndromes are rare, with limited pathophysiological understanding. Case Presentation: A 53-year-old male developed Miller Fisher syndrome following respiratory infection, progressing to pharyngeal-cervical-brachial variant within 72 hours. Comprehensive immunological evaluation revealed triple ganglioside antibody positivity (anti-GT1a, anti-GQ1b, and anti-sulfatide), correlating precisely with clinical phenotype. Treatment with intravenous immunoglobulin following plasma exchange complications achieved complete functional recovery and antibody seroconversion within 18 days. Conclusions: This overlap syndrome with triple ganglioside antibody positivity supports molecular mimicry mechanisms in autoimmune peripheral neuropathies. The direct correlation between antibody profile and clinical phenotype provides insights into pathophysiological mechanisms and emphasizes the importance of comprehensive immunological evaluation in atypical presentations.