Necrotizing vasculitis in a case of disseminated neonatal herpes simplex infection.

A term newborn suffered disseminated herpes simplex virus (HSV) type II infection five days after cesarean section delivery for fetal distress. The mother had no history or evidence of herpetic lesions; the father had a history of genital herpetic lesions. The infant's terminal course was dominated by disseminated intravascular coagulation (DIC) with hepatic and renal failure. Microscopic examination revealed a necrotizing vasculitis of small and medium-sized lung and peripancreatic arteries. Nuclear inclusions characteristic of HSV were found in these arteries, as well as in the adrenal parenchyma, spleen, and lymph node; electron microscopy confirmed replication of virus within the arterial endothelial cells. The mechanism of arterial damage in severe herpetic infection contrasts with the immune-complex mechanism postulated for other viral vasculitides. Direct, virally induced arterial damage resulting in exposure of collagen may set the stage of DiC, a commonly fatal complication of this disease.