TLR4,MIP-1α,and TIM-4 in relation to the occurrence and prognosis of pulmonary infection in patients with severe traumatic brain injury

Cao Guanghui; Pan Qi; Han Bin; Liu Tao; Tang Chao; Ding Yi; Qiu Shengli

doi:10.11986/j.issn.1673-873X.2025.10.15

Abstract：Objective To analyze the relationships between serum Toll-like receptor 4(TLR4),macrophage inflammatory pro-tein-1α(MIP-1α),and T-cell immunoglobulin,and mucin domain-containing protein 4(TIM-4)and the occurrence and prog-nosis of pulmonary infection in patients with severe traumatic brain injury(sTBI),and to evaluate the predictive value of these serum markers for pulmonary infection and prognosis in sTBI patients,aiming to provide a reference for clinical decision-mak-ing.Methods A total of 182 patients with sTBI admitted to our hospital from January 2022 to January 2025 were enrolled.According to whether pulmonary infection occurred,patients were assigned to an infection group(n=75)and a non-infection group(n=107).Patients with pulmonary infection were further classified by outcome into a good-prognosis group(n=43)and a poor-prognosis group(n=32).Serum TLR4,MIP-1α,and TIM-4 levels were measured on admission.Logistic regres-sion analysis was used to analyze the associations of serum TLR4,MIP-1α,and TIM-4 with pulmonary infection and progno-sis;receiver operating characteristic(ROC)curves were used to evaluate the predictive performance of these markers.Results Compared with the non-infection group,patients in the infection group had significantly higher TLR4,MIP-1α,and TIM-4 levels(P<0.05).Among patients with pulmonary infection,those with poor prognosis had significantly higher TLR4,MIP-1α,and TIM-4 levels than those with good prognosis(P<0.05).Logistic regression analysis showed that elevated TLR4(OR=1.497,95%CI:1.265-1.772),MIP-1α(OR=1.080,95%CI:1.027-1.136)and TIM-4(OR=1.073,95%CI:1.041-1.106)were independent risk factors for pulmonary infection in sTBI patients;likewise,increased TLR4(OR=2.191,95%CI:1.336-3.594),MIP-1α(OR=1.324,95%CI:1.122-1.562)and TIM-4(OR=1.112,95%CI:1.029-1.201)were independent risk factors for poor prognosis among sTBI patients with pulmonary infection.ROC analysis demon-strated that the combined prediction model using TLR4,MIP-1α,and TIM-4 yielded an AUC of 0.843(95%CI:0.782-0.892)for predicting pulmonary infection,with a sensitivity of 73.33%and specificity of 87.85%;the combined model out-performed each marker alone(P<0.05).For predicting prognosis among infected patients,the combined markers produced an AUC of 0.880(95%CI:0.784-0.944),with a sensitivity of 84.37%and specificity of 83.72%,again superior to indi-vidual markers,with significant differences(P<0.05).Conclusion TLR4,MIP-1α,and TIM-4 levels are closely correlated with both the occurrence of pulmonary infection and clinical outcomes in patients with sTBI.Joint measurement of these mark-ers improves the prediction of pulmonary infection and prognosis and may provide useful guidance for clinical management.