Association of length of hospital stay, total body surface area burned, and Carbapenem-Resistant Klebsiella pneumoniae infection in burn patients: A retrospective study

Background: The specific relationships between total body surface area burned (TBSA), length of stay (LOS), and carbapenem-resistant Klebsiella pneumoniae (CRKP) infection remain unclear. This study aimed to explore the relationship between TBSA and CRKP infection and to examine whether LOS mediates the association between TBSA and the risk of CRKP infection. Methods: We retrospectively collected the clinical data of adult burn patients admitted to Nanyang Nanshi Hospital between 2021 and 2023. We used multivariate logistic regression analysis to study the risk factors for CRKP infection; restricted cubic spline analysis to investigate the associations between TBSA, LOS, and CRKP infection; and mediation analysis to examine whether LOS mediated the association between TBSA and CRKP infection. Results: A total of 178 subjects were included in the study; 104 (58.4 %) were male, and the median age was 47 (33-59) years. Thirty-one (17.4 %) subjects developed CRKP infection. Both TBSA and LOS showed a linear positive correlation with the risk of CRKP infection. The LOS mediated the association between TBSA and incident CRKP infection, with a proportion of 17.6 %. Conclusion: The risk of CRKP infection linearly increased as TBSA or LOS increased, and LOS mediated approximately 20 % of the total association between TBSA and CRKP infection.