Objective To detect the disparity of three biological molecules Caveolin-1,IL-1β,VEGF in cerebrospinal fluid of children with viral encephalitis at the different stages; to explore the role of Caveolin-1,IL-1β,VEGF in the pathogenesis of viral encephalitis;and to evaluate their clinical significance in assessing the severity and prognosis of viral encephalitis.Methods We recruited 65 inpatients children with viral encephalitis in the Second Neurology Department of Hunan Children's Hospital from July 2011 to July 2012.Subjects were divided into 2 groups:54 cases of acute phase and 11 cases of recovery phase.According to the clinical manifestations,they were re-divided into 40 patients with mild viral encephalitis and 25 cases of severe viral encephalitis.Twenty healthy age matched controls (10 cases of epilepsy and 10 cases of congenital abnormality) were also taken for the study.Cerebrospinal fluid exam,EEG,head MRI and other tests were performed in all patients.Caveolin-1,IL-1β and VEGF levels in cerebrospinal fluid of 65 children with viral encephalitis and 20 age-matched controls were measured using ELISA.Results Cerebrospinal fluid Caveolin-1,IL-1β,VEGF levels in the acute phase of viral encephalitis were (49.209 ± 22.320) pg/ml,(16.923 ± 6.823) ng/ml,(44.342 ± 19.264) ng/ml respectively,and (33.253 ± 20.349)pg/ml,(11.724 ± 3.009)ng/ml,(30.312 ± 18.147) ng/ml in recovery phase,which were significantly higher than those of controls (P <0.01).The difference was statistically significant between acute phase and recovery phase (P < 0.05).Acute viral encephalitis patients had higher Caveolin-l,IL-1β,VEGF levels than the epilepsy group,and the difference was statistically significant (P < 0.05).In viral encephalitis group,children with cerebrospinal fluid protein content (0.5 ~ 1.0 g / L) had higher of Caveolin-1,IL-1β and VEGF levels as compared with those with cerebrospinal fluid protein content ≤ 0.5 g/L,and the difference was statistically significant (P < 0.01).Cerebrospinal fluid Caveolin-1,IL-1 β and VEGF showed no significant difference among children with different severity of encephalitis,different levels of frequent seizures,different degrees EEG changes (P > 0.05).But in the patients with severe head MRI changes,cerebrospinal fluid Caveolin-1,IL-1β,VEGF levels increased significantly (P < 0.05).Conclusions Caveolin-1,IL-1β and VEGF may participate in the pathogenesis of viral encephalitis.Detection of these parameters may be helpful to the evaluation of the severity and prognosis of viral encephalitis. Key words: Viral encephalitis; Caveolin-1 ; Interleukin-1β; Vascular endothelial growth factor