Guillain-Barré syndrome associated with CASPR2 antibodies: two paediatric cases.

The pathogenesis of Guillain-Barré syndrome (GBS) is considered to be, at least in part, mediated by autoantibodies directed against neuronal antigens. Antibodies to contactin-associated protein-like 2 (CASPR2), part of the voltage-gated potassium channel complex (VGKC-complex), are associated with neurological disease predominantly affecting the peripheral nervous system but are not known to be associated with GBS. We report two cases of ganglioside antibody-negative paediatric GBS associated with CASPR2 antibodies. Both patients made a complete clinical recovery. The tissue distribution and function of CASPR2 make it a biologically plausible autoimmune target in GBS and its clinical relevance in GBS should be determined in further studies.