To compare the prevalence and subtypes of movement disorders at presentation to the post-recovery phase in patients with antibody-positive autoimmune encephalitis.

Movement disorders are frequently associated with autoimmune encephalitis and while the acute presentation of movement disorders in autoimmune encephalitis is well-documented, residual movement disorders are understudied.  

We retrospectively evaluated patients referred to the neuroimmunology clinic diagnosed with antibody-positive autoimmune encephalitis. We analyzed movement disorders at presentation, first post-treatment follow-up, and the latest available follow-up.

This interim analysis included thirty patients diagnosed with antibody-positive autoimmune encephalitis (53.3% female, average age 49.3, SD 17.9). The patients were positive for the following neuronal antibodies: high titer GAD65 (10), NMDAR (8), GFAP (6), LGI1 (4), VGCC (3), anti-Yo (2), D-1 (1), Amphiphysin (1). Nineteen patients (63.3%) had movement disorders at presentation. At first follow-up, eleven (61.1%) of those patients still had movement disorders while only seven (38.9%) had residual movement disorders at the latest follow-up. The movement disorder phenotypes at presentation included dystonia (8 patients), catatonia (5), spasms (4), stereotypies (3), chorea (2), stiff person syndrome (SPS) (2), myoclonus (2), acquired parkinsonism (2), ataxia (2), dyskinesia (1), spontaneous clonus (1), spasticity (1), and complex tics (1). The most common residual movement disorders were acquired parkinsonism (3), dystonia (3), SPS (2), spasms (2), ataxia (2), and complex tics (2).

Among patients referred to neuroimmunology clinic with antibody-positive autoimmune encephalitis, the presence of movement disorders upon presentation is relatively common but only about a quarter of patients will have residual movement disorders after recovery.