Opsoclonus-myoclonus syndrome after adenovirus infection

Abstract

Autoimmune and paraneoplastic movement disorders are rare in childhood. Diagnosis often relies on clinical manifestations and clinicians' recognition. A 22-month-old girl at onset of opsoclonus-myoclonus syndrome (OMS) was followed for 8 years. Adenovirus (type C subtype 3) infection coincided with manifestation. Data on treatment, imaging and follow-up are provided. In the spinal fluid, elevated anti-rubella antibodies and oligoclonal bands were detected. An autoimmune process affecting mainly cerebellar neurons was revealed immunohistochemically. Moderately intense long-term immunosuppressive therapy resulted in a favorable clinical outcome. A video demonstrated severe OMS manifestations at onset, followed by nearly complete recovery after treatment. We describe the association of a parainfectious OMS and adenovirus infection; laboratory results indicate a non-specific humoral process affecting mainly cerebellar neurons. Our video documentation will aid to recognize this rare movement disorder and to initiate early treatment.

Keywords: Ataxia; Autoimmune; Children; Encephalopathy; Movement disorder.

Fig. 1

Double immunofluorescence labeling of cerebellar frozen sections from a human autoptic case. Binding sites for autoantibodies from the patient (green) and astroglial or neuronal markers (red) are concomitantly revealed by confocal laser-scanning microscopy. Autoantigens are stained by patient’s serum (1:20) and carbocyanine (Cy) 2-conjugated anti-human IgG + IgM, while astroglia and neurons are visualized by appropriate Cy3-coupled secondary antibodies. a At lower magnification, the cerebellar subcortex displays layers of granular cells immunoreactive for the patient’s serum—clearly distinguishable from immunoreactivity for rabbit-anti-glial fibrillary acidic protein (GFAP; Dakocytomation; 1:1000). b At higher magnification, autoantibodies bind cells of deep cerebellar nuclei lacking GFAP immunolabeling. c In the cerebellar cortex, Purkinje cells are stained by patient’s serum while rabbit-anti-S100β (Swant; 1:500) predominantly demonstrates protoplasmic astroglia. d Immunodecoration of probably neuronal surface antigens with patient’s serum is located apart from labeling achieved with mouse-anti-neuronal nuclei (NeuN; Millipore; 1:100) in the layer of deep cerebellar neurons. Scale bars in a, c = 200 µm, in b, d = 50 µm

Fig. 2

Sagittal T2-weighted cranial magnetic resonance images at onset of opsoclonus-myoclonus syndrome (a) and 5 years later (b), showing mild cerebellar atrophy with widened sulci and extracerebellar spaces