Detection of hemophagocytes in blood smears in fatal disseminated neonatalherpes simplex virus infection

Three cases of fatal neonatal herpes simplex virus (HSV) infection are repo rted. All cases developed fever on days 2-3 after birth and severe liver da mage on days 7-8, and subsequently died of multiple organ failure due to se vere hemophagocytic lymphohistiocytosis. Upon retrospective examination, mu ltiple vacuolated macrophages and hemophagocytes were noted in peripheral b lood smears as early as day 5 in these cases. Since the findings of hemopha gocytosis might point to serious viral infection in neonates, careful readi ng of blood smears may help in formulating a presumptive diagnosis of HSV i nfection, thus allow prompt antiviral therapy to improve the prognosis in t his highly fatal disease.