Researchers at University Hospitals of Ferrara and Padova, Italy, report a case of cerebral infarction and stroke occurring 3 months after varicella-zoster virus (VZV) infection in a 5-year-old immunocompetent child, and they provide a literature review of 70 similar cases. The child was admitted with a left hemiparesis of 10 days duration and gradual onset without fever or impaired consciousness. She had a past history of chickenpox at age 1 year and reactivation of VZV infection affecting the trunk 3 months before admission. Laboratory tests for other causes of stroke were negative. MR angiography showed narrowing of the right middle cerebral artery, compatible with infarction and vasculitis. CSF showed a protein of 98 mg/dL, and PCR evidence of VZV-DNA. Heparin and acyclovir were started and 10 days later, aspirin (50 mg/day) to prevent recurrence of infarction. The paresis improved and at 1-year follow-up, she had minimal reduction in motility of the left arm and leg during sports. MRI showed punctate gliosis and malacia in right semiovale.
A total of 70 published cases of childhood stroke syndrome associated with VZV are reviewed, median age 5 years (range 6 months-11 years), 43 boys and 28 girls; 10 patients (14%) had underlying diseases or prothrombotic conditions (diabetes, AIDS, patent foramen ovale, iron deficiency anemia, protein C deficiency) and 61 (86%) were previously healthy and without risk factors for stroke. Stroke was preceded by chickenpox in 90% cases and by herpes zoster in 10%, mainly ophthalmic HZ. In 2 cases, stroke followed vaccination with VZV, and in one at birth secondary to maternal HZ in the 3rd trimester of pregnancy. Median interval between chickenpox or HZ and stroke was 18 weeks (range, 0-4 years). Stroke preceded chickenpox exanthema by 24 hours in 1 case and 2 weeks after viral exposure. Role of treatment is unclear (no treatment in 17%, aspirin in 52%, acyclovir 44%, corticosteroids 40%, heparin 15%) and outcome is usually good, with complete recovery in 50%, including those untreated. 
COMMENT. History of recent chickenpox or HZ should be considered as a possible cause in a child presenting with ischemic stroke. This report adds support for universal immunization against VZV.
Dr Charles Grose, University of Iowa, who had reviewed all the literature on the complications of varicella infection in children in 1994, reports that stroke was rarely mentioned . MRI is the reason for the emergence of more case reports of stroke after varicella in the past 2 decades. Stroke after zoster infection is more likely if the location is the eye (zoster ophthalmicus). VZV infects the trigeminal ganglion and other cerebral ganglia, and later reactivates, spreading along sensory nerve fibers to an eye and a cerebral artery, where viral replication causes inflammation and thrombosis. Treatment of zoster ophthalmicus with acyclovir is recommended. Neurological complications of VZV have been underestimated.