Varicella-zoster associated cerebral vasculitis (VZCV) as a cause of cerebral infarction has hitherto been considered a rare condition. Ischemic stroke in previously healthy children has occurred during recovery from chickenpox or has been attributed to virus reactivation among immunosuppressed patients. The clinical, radiologic and immunologic findings in four children with VZCV will be reported. Clinical manifestations included sudden onset of hemiparesis, motor aphasia and disturbed consciousness in previously healthy children. Only one child had a history of chickenpox six weeks prior to the onset of stroke, whereas a latency period of up to four years between chickenpox and the onset of stroke was found in the other three children. Diagnosis of VZCV was confirmed repeatedly by demonstrating intrathecal production of varicella-zoster IgG antibodies in three children or a four-fold increase of varicella-zoster serum IgA-antibodies in one child. Intrathecal production of antibodies against other latent viruses and borreliosis could be excluded. PCR for varicella on CSF, performed in two patients, remained negative. No intrathecal production of varicella-zoster antibodies has been found in a control group of twenty clinically healthy children (age range from 2-18 years) with a previous varicella infection. During follow-up two children recovered completely whereas two children still suffer from serious neurological deficits. Immunological investigations, performed in three children, showed circulating immune-complexes with slightly lowered complement concentrations in two patients. In addition a lowered T-helper/T-suppressor cell ratio of unknown origin was found in three children. These immunological findings will be discussed in the light of the pathophysiology of VZCV.