Investigation of HSV-1, HSV-2, CMV, HHV-6 and HHV-8 DNA by real-time PCR in surgical resection materials of epilepsy patients with mesial temporal lobe sclerosis

Objective: The objective of this study is to investigate the presence of viral DNAs of HSV-1, HSV-2, HHV-6, HHV-8, and CMV in hippocampus of the patients with mesial temporal lobe epilepsy (MTLE) syndrome. Methods: Pathological specimens were obtained from 33 patients with MTLE undergone temporal lobectomy with amygdalo-hippocampectomy due to intractable seizures. Autopsy materials from the hippocampus of 7 patients without neurological disease were used as controls. The data was also correlated with the clinical history of patients including febrile convulsions, age, and history of CNS infections. Real-time polymerase chain reaction method was performed for detection of DNAs of these viruses. Results: HHV-6, HSV-1 and HHV-8 were detected in the hippocampus of 3, 2 and I patients with MTLE respectively. None of the hippocampus of patients with MTLE was positive for DNA of HSV-2 and/or CMV Three patients with positive HHV-6 DNAs had febrile convulsions and family history for epilepsy. None of our control specimens showed PCR positivity to any of the 5 tested viruses. Conclusions: Our study is the first to report the presence of HHV-8 viral genome in the brain tissue of patient with MTLE. Viral DNAs were detected in a total of 18% of the patients in this study; we can conclude that activity of the latent virus in patients with hippocampal sclerosis should be more extensively studied to establish its role in active infection. (c) 2007 Elsevier B.V. All rights reserved.