Miller Fisher Syndrome in Morocco: A 14-Year Retrospective Study of 27 Cases at a Tertiary Neurology Center

Introduction: Miller Fisher syndrome (MFS) is a rare, acute immune-mediated neuropathy characterized by the classic triad of ophthalmoplegia, ataxia, and areflexia. Epidemiological and clinical data from North Africa remain scarce. The primary objective of this study was to provide a comprehensive description of the epidemiological, clinical, neurophysiological, and outcome characteristics of MFS in a Moroccan population. The secondary objective was to analyze these findings in comparison with existing literature. Methods: We conducted a retrospective descriptive study in the Neurology Department of Mohammed VI University Hospital in Marrakech, Morocco, over a 14-year period (January 2010-December 2024). Patients were included based on the presence of the classical clinical triad or compatible clinical features supported by cerebrospinal fluid (CSF) findings and anti-GQ1b antibody testing. Results: A total of 27 patients were included (mean age 40.2 ± 16.1 years, range 7-70). A female predominance was observed (n=17, 63%; male-to-female ratio: 0.59), and a seasonal peak occurred during winter in 14 patients (50%). Antecedent infections were reported in 15 patients (55.6%), most commonly respiratory infections (33%). The complete clinical triad was present in eight patients (29.6%). Areflexia was most frequent (77.7%), followed by ataxia (70.3%) and ophthalmoplegia (66.7%). Motor weakness and sensory disturbances were observed in 51.9% and 55.6% of patients, respectively. Albuminocytologic dissociation was found in 59.3% of cases, and anti-GQ1b antibodies were positive in 69.2% of patients, as all patients underwent antibody testing. Regarding treatment, 59.3% received intravenous immunoglobulins and 25.9% underwent plasmapheresis; outcomes were favorable, with complete recovery in all patients at six months. Conclusion: This study represents one of the largest reported series of MFS from North Africa and provides a detailed descriptive characterization of the disease in a Moroccan cohort. While trends such as female predominance and winter peak were observed, these should be interpreted with caution due to the small sample size and retrospective design. Similarly, although most patients received immunotherapy and achieved full recovery, causal inferences regarding treatment efficacy cannot be drawn. Despite frequent overlap with Guillain-Barré syndrome manifestations, the overall prognosis in this cohort was excellent.