Abstract: Objective To study the role of complement C3 and C4 in the early identification of premature infants with early-onset sepsis, and to analyze their predictive value for sepsis complicated with different sites of infection.Methods The clinical data of 72 preterm infants with sepsis (sepsis group) and 18 normal preterm infants (control group) were retrospectively analyzed, who were treated in the First Affiliated Hospital of Zhengzhou University from Jan. 2022 to Dec. 2022. The difference in complement levels between the two groups was analyzed. The sepsis group was divided into three subgroups: sepsis with suppurative meningitis group, sepsis with shock group and simple sepsis group. The differences in complement levels between the three subgroups and the normal control group were compared. ROC curve was used to analyze the predictive value of complement levels for infection in the three subgroups.Results There was no significant difference in complement levels between the sepsis group and the normal control group(P>0.05). The level of complement C3 and C4 in sepsis with suppurative meningitis group was higher than that in control group, and the difference was statistically significant (P<0.05). The levels of complement C3 in the sepsis with shock group and the simple sepsis group were lower than those in the control group, and the differences between the two groups were statistically significant(P<0.05). The levels of complement C4 in the sepsis with shock group and the simple sepsis group were lower than those in the control group, but the difference was not statistically significant(P>0.05). The predictive value of complement level for sepsis combined with shock and sepsis alone was high, but the predictive value for sepsis combined with suppurative meningitis was not high.Conclusion Complement levels are significantly different in children with sepsis complicated with different sites of infection or at different stages of the same infection. Dynamic detection of complement levels may be helpful for the early diagnosis and differential diagnosis of sepsis and its corresponding complications in preterm infants.

Key words:

Sepsis；Complement C3, Complement C4, Sepsis with suppurative meningitis, Sepsis with shock, Preterm infants