Acute Hemichorea Can Be the Only Clinical Manifestation of Post-Varicella Vasculopathy: Two Pediatric Clinical Cases.

Acute hemichorea can occur in the context of infectious, autoimmune, metabolic, toxic, and vascular neuropathologies. Primary infection by varicella zoster virus (VZV) can result in vasculopathy with neurological manifestations, such as hemiparesis, at times accompanied by hemichorea. Isolated hemichorea, however, had not been reported. We here describe two cases of VZV-induced vasculopathy whose sole clinical manifestation was acute hemichorea. Both cases involved young boys of 3 years of age, who presented with acute hemichorea 4-6 months after initial VZV infection. All hematological, immunological, and toxicological tests were normal, except for the presence of VZV IgG. Brain structural magnetic resonance imaging (MRI) and magnetic resonance angiography revealed specific signs of vasculitis and ischemic lesions in the basal ganglia region (lentiform nucleus, thalamus, and internal capsule). Following corticosteroid and acetylsalicylic acid treatment, full symptomatic recovery was achieved within 3 weeks. Repeated MRI documented full neurostructural recovery, which was confirmed at extended follow-up for more than 1 year. These cases indicate that VZV-induced vasculopathy should be considered in the case of pediatric isolated acute hemichorea.