Detection Of Borna Disease Virus P40 Gene In The Blood And Cerebrospinal Fluid Of Viral Encephalitis Patients

Objective: To discuss the infection situation of Borna disease virus(BDV) in patients with viral encephalitis(VE) in Zunyi city of Guizhou province and to study the characteristics of BDV p40 gene, to summarize the clinical characteristics of the viral encephalitis patients whose the BDV p40 gene is positive in Peripheral blood mononuclear cell(PBMC) or Cerebrospinal fluid(CSF).Methods: The BDV p40 gene in CSF and PBMC of 43 viral encephalitis patients and 45 control patients without nervous system disease who were not infected with usual virus but with surgical operations were examined by the reverse transcriptase PCR and fluorescence quantitative PCR(FQ-RT-PCR), identified and analyzed the nucleotide sequence of the BDV p40.Results: It was found that the positive rate of the BDV p40 gene in peripheral blood mononuclear cell(PBMC) of patients with VE was 6.97%(3/43), and it was higher than that of the control patients 0/45(0%), but there was no statistical significance for the differences(P﹥0.05), and the positive rate of BDV p40 gene in CSF of patients with VE was 6/43(13.9%) and the differences with the control patients exist statistical significance(P﹤0.05); 2 of 6 case with BDV p40 gene in CSF were also positive in PBMC. The homologies of gene sequence of aim gene fragment amplified by PCR with the standard virus strains V and He/80 supplied by NCBI web station of Gen Bank were separately 100%、98.7%, there was only synonymous mutation(nt609:A�'G) between the aim gene fragment and He/80, which was not changed the sequence of amino acid. The probability of mental behavior of VE patients carrying the BDV p40 gene was 71.5%(5/7), and The probability of mental behavior of VE patients without the BDV p40 gene was 16.7%(6/36), the differences between two groups were statistically significant(P ﹤ 0.05); the coincidence of secondary epilepsy of the VE patients who carried the BDV p40 gene was28.6%(2/7) and the VE patients without the BDV p40 gene was 0%(0/36), There is the statistical significance the difference between the two group(P﹤0.05).Conclusion: These results suggest that BDV infection really exists in patients with VE in Zunyi city and the surrounding regions of Zunyi and the infection of BDV may relate to the VE which the pathogen was unknown; The BDV p40 gene is very conservative and rare mutational and it may be a specific marker to prove the patients really infected by the BDV; the clinical characteristics of the VE patients who carried the BDV p40 gene may have psychic or behavioral abnormal and secondary epilepsy.