Miller Fisher syndrome in infancy

Pediatric Miller Fisher Syndrome; Characteristic Presentation and Comparison with Adult Miller Fisher Syndrome

Background: We aimed to investigate the characteristic presentation of Miller Fisher syndrome (MFS) in pediatrics and compare it with that in adults. Methods: We performed a retrospective review of medical records, laboratory findings, and disease course of pediatric MFS. The data were compared with those of adult MFS, and literature review was done. Unpaired and paired comparisons between groups were made using Wilcoxon rank-sum and signed-rank tests, respectively. Results: Median age for pediatric MFS was 9.8 ± 6.5 years. There were 5 (45.5%) male and 6 (54.5%) female patients. All patients had preceding infection. Two patients (22.2%) had tested positive for anti-GQ1b antibody. Ten patients (90.1%) were treated with intravenous immunoglobulin, and 2 (18.2%) also received intravenous methylprednisolone. Within one month, 8 (72.7%) patients showed recovery, and all 11 (100%) recovered fully within 3 months. Further, the pediatric group had higher frequency of unilateral involvement of ophthalmoplegia, ataxia, and autonomic symptoms but lower antiganglioside antibody positivity and manifestations of areflexia than the adult group. Conclusions: Neuro-ophthalmic manifestations and disease course of pediatric MFS were similar to those of adult MFS as stated in the literature. However, the presence of autonomic symptoms was higher and anti-GQ1b antibody positivity was lower in pediatric MFS than in adult MFS.

Clinical and immunological spectrum of the Miller Fisher syndrome

The Miller Fisher syndrome (MFS), characterized by ataxia, areflexia, and ophthalmoplegia, was first recognized as a distinct clinical entity in 1956. MFS is mostly an acute, self-limiting condition, but there is anecdotal evidence of benefit with immunotherapy. Pathological data remain scarce. MFS can be associated with infectious, autoimmune, and neoplastic disorders. Radiological findings have suggested both central and peripheral involvement. The anti-GQ1b IgG antibody titer is most commonly elevated in MFS, but may also be increased in Guillain-Barré syndrome (GBS) and Bickerstaff's brainstem encephalitis (BBE). Molecular mimicry, particularly in relation to antecedent Campylobacter jejuni and Hemophilus influenzae infections, is likely the predominant pathogenic mechanism, but the roles of other biological factors remain to be established. Recent studies have demonstrated the presence of neuromuscular transmission defects in association with anti-GQ1b IgG antibody, both in vitro and in vivo. Collective findings from clinical, radiological, immunological, and electrophysiological techniques have helped to define MFS, GBS, and BBE as major disorders within the proposed spectrum of anti-GQ1b IgG antibody syndrome.