Background: To study the presence of anti-GQ1b antibodies as a tool for the diagnosis of Miller-Fisher syndrome (MFS).
Patients and method: We studied 54 patients with probable diagnosis of MFS and 10 patients diagnosed as Guillain-Barré syndrome plus ophthalmoplegia (1 case), Bickerstaff's encephalitis (1 case), relapsing ophthalmoplegia (7 cases) and relapsing diplopia (1 case). Results were compared with 130 patients with other disimmune neuropathies. Antibodies were detected by ELISA and checked by thin layer chromatography. Campylobacter jejuni serology was studied using a complement fixation test.
Results: Diagnosis of MFS was confirmed in 38 patients. A 97.3% were positive for GQ1b, being all negative for Campylobacter jejuni serology. A second test after 4-5 weeks of nadir was negative in 84.2% (16/19), concomitant with clinical recovery.
Conclusions: Anti-GQ1b antibodies are useful markers for the differential diagnosis of MFS, specially with some acute brainstem disorders. Testing must be performed during the first four weeks of clinical course. This correlation between the triad ataxia, arreflexia and ophthalmoplegia and anti-GQ1b antibodies confirms that they are highly specific of MFS.