Giant serpentine aneurysm of vertebrobasilar artery mimicking dolichoectasia--an unusual complication of pediatric AIDS. Report of a case with review of the literature.

Central nervous system manifestations of acquired immunodeficiency syndrome (AIDS) in children differ strikingly from adults. Developmental delay, subacute AIDS encephalitis and basal ganglia calcification are common in children, in contrast to opportunistic infections and dementia in adults. Intracranial aneurysms are being recognized with increasing frequency in pediatric AIDS. Fusiform dilatation of vessels of circle of Willis to form large aneurysms, termed cerebral aneurysmal childhood arteriopathy, is an exceedingly rare complication of pediatric AIDS. We report a case of massive fusiform dilatation of vertebrobasilar system mimicking congenital dolichoectasia with evidence suggesting direct causation by HIV-1 Clade C virus. In view of scant literature that exists on this unusual complication of pediatric AIDS, we present a detailed review of all previously recorded cases and review the etiopathogenesis. There are 20 reports (32 cases) on record till date that have mostly involved the anterior circulation, occurring between 4-15 years of age. Occurrence is associated with profound immunosuppression, and perinatally acquired HIV with latent interval of 5.5-11 years to onset of symptoms. Direct causation by HIV is favored as reports demonstrate presence of virus in affected vessels, association with high viral load and, more conclusively, arrest in progression or reversal with early initiation of highly active antiretroviral therapy (HAART). The fusiform nature and location of these aneurysms makes any form of surgical intervention or embolization impossible. High degree of clinical suspicion and awareness of this entity is, therefore, important as this can place young patients at risk for major cerebrovascular accidents.