Abstract: Objective To explore the predictive value of expression and secretion of RANTES(regulated upon activation, normal T cell expressed, and secreted) and leukotriene C4 (LTC4) by peripheral T cells on disease outcomes in patients with autoimmune encephalitis (AE). Methods The patients with AE (144 cases) admitted from August 2020 to August 2024 were selected as the AE group and then were divided into the good prognosis group (98 cases) and the poor prognosis group (46 cases) based on the disease outcomes. Another 120 patients with viral encephalitis (VE) were selected as the VE group, and 150 healthy medical checkup participants were selected as the control group. ELISA was used to detect serum CRP, IL-6, TNF-α, RANTES, and LTC4. The data and serum level of RANTES and LTC4 were compared among different groups. The data and serum RANTES and LTC4 level were compared among patients with different prognoses. Pearson method was used to explore the correlation between RANTES,LTC4 with CRP, IL-6, and TNF-α. Multivariate logistic regression was used to explore the influencing factors of poor prognosis in AE patients. ROC curve was plotted to explore the predictive value of serum RANTES and LTC4 in predicting poor prognosis in AE patients. Results The serum RANTES and LTC4 decreased sequentially in AE group, VE group and in control group (P＜0.05). The poor prognosis group had higher serum level of CRP, IL-6, TNF-α, RANTES, and LTC4 than the good prognosis group (P＜0.05). Serum RANTES and LTC4 were positively correlated with CRP, IL-6, and TNF-α(P＜0.05). Serum CRP, IL-6, TNF-α, RANTES, and LTC4 were influencing factors for poor prognosis in AE patients (P＜0.05). The union of serum RANTES and LTC4 had a higher predictive value for poor prognosis in AE patients than individual predictions(Z_RANTES-union=2.722, P_RANTES-union＜0.01; Z_LTC4-union=2.343, P_LTC4-union＜0.05). Conclusions Serum level of RANTES and LTC4 is elevated in AE patients and closely related to the disease outcomes. The combination of serum level of RANTES and LTC4 has a high value in predicting poor prognosis in AE patients.

Key words: autoimmune encephalitis, regulated upon activation, normal T cell expressed, and secreted(RANTES), leukotriene C4, disease outcomes