A patient with a Caspr2 autoantibodies–associated syndrome had an unusual clinical triad
and an excellent response to B-cell–anergizing therapy using the humanized monoclonal antibody
tocilizumab directed against the interleukin 6 (IL-6) receptor.
A 55-year-old man had an atypical clinical triad of epilepsy, dysarthria, and paroxysmal
kinesigenic dystonia, and a high titer of Caspr2 antibodies was detected in his serum and
cerebrospinal fluid. Screening for underlying neoplasias was negative. With initial
methylprednisolone sodium succinate and alternate treatment using plasma exchange and
immunoabsorption as well as subsequent IL-6 receptor blockade through tocilizumab, a complete and
stable remission of symptoms has been achieved throughout the follow-up period of 7 months.
Conclusions and Relevance
In our patient, the implementation of a B-cell–anergizing therapy using tocilizumab, a
humanized monoclonal antibody against the IL-6 receptor, has shown an excellent response. Larger
case series or even controlled studies are needed to confirm the efficacy of tocilizumab in
autoimmune synaptic or presynaptic diseases.