OBJECTIVE To investigate the risk factors for pulmonary infections in long-term bedridden patients after spinal surgery and the predictive value of Toll-like receptor 7(TLR7), interleukin-23(IL-23) and IL-17 signaling pathway.

METHODS Totally 123 patients who were admitted to the Affiliated Hospital of Shaoxing University of Arts and Sciences from Jan. 2019 to Sep. 2022, who were bedridden for a long time period after spinal surgery without complication of pulmonary infections, were collected as the uninfected group, and 33 patients who were treated in the hospital during the same period, and who were bedridden for a long time period after spinal surgery with complication of pulmonary infections, were selected as the infected group. The risk factors for pulmonary infection for patients who were bedridden for a long time after spinal surgery were summarized by multivariate Logistic regression analysis, and the predictive value of the signaling pathway of TLR7, IL-23 and IL-17 on the pulmonary infections of patients who were bedridden for a long period of time were analyzed by receiver′s operating characteristics (ROC) curve.

RESULTS The results of multivariate logistic regression analysis showed that chronic pulmonary disease, combined diabetes mellitus and mechanical ventilation were all the risk factors for pulmonary infection in patients who were bedridden for a long time after spinal surgery (OR=3.323, 2.646, 2.259, P < 0.05). The area under the curve (AUC) value of the combined detection for the prediction of pulmonary infection in patients who have been bedridden for a long time after spinal surgery was higher than that of TLR7 mRNA, IL-23 and IL-17 alone (P < 0.05). TLR7 mRNA and the combined sensitivity were higher than those of IL-23 and IL-17 (P < 0.05). The specificity of IL-23 and its combination was higher than that of TLR7 mRNA and IL-17(P < 0.05), and the specificity of IL-17 was higher than that of TLR7 mRNA (P < 0.05).

CONCLUSION The susceptible factors for the occurrence of pulmonary infection in long-term bedridden patients after spinal surgery included chronic pulmonary disease, combined diabetes mellitus and mechanical ventilation, while the combination of TLR7/IL-23/IL-17 signaling pathway-related indexes had good predictive value for the occurrence of pulmonary infection in long-term bedridden patients after spinal surgery. Clinically, targeted intervention or treatment can be carried out for long-term bedridden patients after spinal surgery according to their relevant susceptible factors and protective factors to reduce the risk of pulmonary infection.