Abstract: Objective To investigate the distribution of pathogenic bacteria in intracranial infections after severe traumatic brain injury (STBI) surgery and the clinical value of serum Clara cell protein 16 (CC16) and suppressor of cytokine signaling-3 (SOCS-3) levels.Methods A total of 102 STBI patients attending our hospital between May 2019 and June 2023 were selected as study subjects and divided into infected group (38 cases) and uninfected group (64 cases) according to their postoperative intracranial infection status.Automated bacterial tester was used to detect the distribution of pathogenic bacteria in patients in the infected group;clinical data of patients were collected and analyzed;ELISA was used to detect CC16 and SOCS-3 expression in the serum of STBI patients.Multivariate Logistic regression was used to analyze the factors influencing postoperative intracranial infection in patients with STBI.ROC curve was used to analyze the predictive value of serum CC16 and SOC-S adjuvant 3 levels for postoperative intracranial infection in patients with STBI.Results Among the 38 intracranial infections after STBI,48 pathogenic strains were isolated,including 30 gram-positive bacteria,accounting for 62.50% of the total pathogens and 18 gram-negative bacteria,accounting for 37.50% of the total pathogens.Among them,Staphylococcus aureus,coagulase-negative Staphylococcus,Acinetobacter bausoni,and Pseudomonas aeruginosa accounted for 33.33%,16.67%,14.58% and 10.42% of the total pathogens.NC,WBC,and SOCS-3 levels in the postSTBI infected group were significantly higher than those in the uninfected group (P<0.05),and CC16 levels were significantly lower than those in the uninfected group (P<0.05).Elevated levels of NC,WBC,and SOCS-3 were risk factors affecting postoperative intracranial infection in STBI patients,and increased CC16 level was a protective factor affecting postoperative intracranial infection (P<0.05).Serum CC16,SOCS-3 levels and combined AUC for postoperative intracranial infection in patients with STBI were 0.830,0.762 and 0.900,respectively,the combined prediction was better than the respective predictions alone (_Zcombined-CC16=2.372,_Zcombination-SOCS-3=2.882,P=0.018,0.004).Conclusion With the high distribution of gram-positive bacteria in patients with intracranial infection after STBI,and decreased serum CC16 levels and increased SOCS-3 level,the combination had a high predictive value of postoperative intracranial infection in patients with STBI.

Key words: severe traumatic brain injury, intracranial infection, distribution of pathogenic bacteria, clara cell protein 16, suppressor of cytokine signaling-3, predictive value