Miller Fisher syndrome [MFS] is an immune mediated polyradiculoneuropathy associated with antiganglioside antibody. The immunopathological mechanism of antiganglioside directly attack the nodal and paranodal regions of peripheral nerve. Though anti-GQ1b antibody was strongly associated with MFS, other antigangliosides and negative antibody cases were occasionally mentioned. This current study reports the clinical characteristic and non-neurological presentation of syndrome of inappropriate antidiuretic hormone [SIADH]. The possible pathophysiology of non-neurological symptoms was briefly reviewed.

Keywords: Miller Fisher syndrome, SIADH, Ataxia, Ophthalmoplegia, Anti-GQ1b antibody