RESUMEN
Encephalitis due to herpes simplex virus [HSV] is the most important cause of fatal Sporadic encephalitis that prompt diagnosis is necessary because there is effective antiviral treatment for this disorder. In the fatal cases, severe meningoencephalitis is associated with diffuse destructive changes in the brain tissue and is following the reactivation of latent virus.Recent studies demonstrate increased hypercoagulopathy state due to HSV infection in the endothelium and footprints of virus has been found in the vascular thrombosis. In this issue, one of the very rare manifestations of HSV encephalitis, which has so far been reported in a neonate, is presented. The patient presented with the signs of encephalitis including stupor state and agitation, headache, seizure and neck stiffness. The diagnosis of HSV encephalitis is confirmed by the PCR test of CSF fluid .MRI and MR venography of the patient's brain demonstrated the thrombosis of sagital, rectus and lateral venous sinus. The patient survived with the specific treatments. Herpes simplex virus type 1 can be a cause for the development of cerebral Venus thrombosis. This case report is a conformation for the studies demonstrating hypercoagulopathy state in the setting of HSV infection