Characteristics of single ocular motor nerve palsy associated with anti-GQ1b antibody

To define the prevalence and characteristics of single ocular motor nerve palsy (OMNP) associated with positive serum anti-GQ1b antibody. We performed a prospective multicenter study that recruited 82 patients with single OMNP without identifiable causes from the history and neuroimaging in six neurology clinics of university hospitals. We measured serum anti-GQ1b antibody in all participants. Twelve patients with multiple OMNP and 30 with identifiable causes served as the controls. Overall, the prevalence of anti-GQ1b antibody syndrome was 10% (8/82) in patients with single OMNP and 6% (5/78) in those with single OMNP in isolation. None of the 14 patients with OMNP with identifiable causes showed positive serum anti-GQ1b antibody. The prevalence of anti-GQ1b antibody syndrome was much higher in patients with multiple OMNP than in those with single OMNP (50% vs. 10%, p < 0.01). Patients with single OMNP and positive anti-GQ1b antibody are younger (42 ± 16 vs. 58 ± 15, p < 0.05) and had a significantly higher frequency of preceding infection (75 vs. 19%, p < 0.05) and other neurological signs (38 vs. 1%, p < 0.05) than those with negative antibody. Eight patients with single OMNP and positive serum anti-GQ1b antibody involved the abducens (n = 6), trochlear (n = 1), or oculomotor nerve (n = 1). Single OMNP accompanying other neurological signs and multiple OMNP are more likely to be associated with anti-GQ1b antibody. Anti-GQ1b antibody syndrome should be considered even in patients with single OMNP, especially when antecedent infection was associated in younger patients.