Central Nervous System Complications of Varicella-Zoster Virus

Abstract

To describe the spectrum of central nervous system complications of varicella-zoster virus (VZV) in children admitted to The Hospital for Sick Children between January 1999 and December2012. Children aged 1month to 18years (n=84) admitted with neurologic manifestations associated with a characteristic VZV rash or a confirmatory laboratory test (positive lesion scraping or cerebrospinal fluid polymerase chain reaction) were included in the study. Acute neurologic complications were included if they occurred within 4weeks of VZV infection. Stroke was considered related to VZV if it occurred within 6months of VZV infection, the neuroimaging was characteristic, and other causes were excluded. Clinical syndromes included acute cerebellar ataxia (n=26), encephalitis (n=17), isolated seizures (n=16), stroke (n=10), meningitis (n=10), Guillain-Barré syndrome (n=2), acute disseminated encephalomyelitis (n=2), and Ramsay Hunt syndrome (n=1). In those with acute complications (nonstroke), neurologic symptoms occurred a median of 5days after rash onset (range -6 to +16). The time between rash onset and stroke ranged from 2weeks to 26weeks (median 16.0weeks). Three children with encephalitis died. Residual neurologic sequelae at one year occurred in 9 of 39 (23%) of children with follow-up data. Only 4 children were reported to have received the varicella vaccine. Neurologic complications of VZV infection continue to occur despite the availability of an effective vaccine. Neurologic symptom onset can predate the appearance of the VZV exanthem and in rare cases may occur in the absence of an exanthem.