Chorea Minor Associated with Anti-Neurochondrin Autoantibodies

Introduction

Chorea minor is characterized by irregular, rapid, and chaotic movements, primarily affecting the hands, feet, and face. Autoimmune chorea minor, the most common form of acquired childhood chorea, is frequently triggered by antineuronal antibodies emerging after A β-hemolytic streptococcal infections,[1] [2] but other immunological abnormalities have also been reported.[3] Recently, antibodies against neurochondrin, an intracellular neuronal target antigen also expressed in striatum, were newly discovered and detected in three adults with cerebellar degeneration.[4] We report a 6-year-old girl who presented with choreatiform movements predominantly of the right arm and face ([Video 1], part I). Diagnostic workup revealed distinctly positive anti-neurochondrin antibodies in the patient's serum[4] ([Fig. 1A], [B]). Intravenous immunoglobulin (IVIG) treatment substantially improved the patient's clinical symptoms ([Video 1], part II), and anti-neurochondrin antibody titers became negative. After 12 weeks of cessation of IVIG treatment clinical symptoms and the autoantibodies reappeared ([Video 1], part III). IVIG treatment was restarted, and the girl's chorea improved again, while anti-neurochondrin autoantibodies ceased to exist ([Video 1], part IV). These observations suggest that anti-neurochondrin autoantibody determination may be meaningful in children with chorea minor.

Video 1 Part I: A 6-year-old girl with involuntary, jerky movements predominantly of the right arm, fidgetiness, and facial grimacing. Part II: Distinct reduction of symptoms during intravenous immunoglobulin (IVIG) treatment. Part III: Symptom relapse after cessation of IVIG therapy. Part IV: Improvement of clinical symptoms after restarting IVIG therapy. Online content including video sequences viewable at: www.thieme-connect.com/ejournals/html/doi/10.1055/s-0037-1606371.

Fig. 1 (A) Indirect immunofluorescence staining of recombinant neurochondrin transfected HEK293 cells incubated with 1:10 diluted patient serum and, in the second step, with fluorescein-labeled sheep antihuman IgG. (B) Antibody titers in relation to clinical symptoms.

• References

• 1 Cardoso F. Autoimmune choreas. J Neurol Neurosurg Psychiatry 2017; 88 (05) 412-417
• 2 Walker KG, Wilmshurst JM. An update on the treatment of Sydenham's chorea: the evidence for established and evolving interventions. Ther Adv Neurol Disorder 2010; 3 (05) 301-309
• 3 O'Toole O, Lennon VA, Ahlskog JE. , et al. Autoimmune chorea in adults. Neurology 2013; 80 (12) 1133-1144
• 4 Miske R, Gross CC, Scharf M. , et al. Neurochondrin is a neuronal target antigen in autoimmune cerebellar degeneration. Neurol Neuroimmunol Neuroinflamm 2016; 4 (01) e307