OBJECTIVE To investigate the pathogenic bacteria of pulmonary infection and the expression of microRNA-1323 (miR-1323)/interleukin (IL)-6 and IL-23/ IL-17 after thoracoscopic radical lung cancer surgery.

METHODS A total of 110 lung cancer patients who underwent thoracoscopic radical resection and developed postoperative lung infection in the Affiliated Hospital of Xuzhou Medical University from Jan. 2019 to Nov. 2023 were selected as the infection group and further sub-grouped according to the prognosis after the surgery for 6 months. Another 110 patients without pulmonary infection after surgery were selected as the uninfected group. Sputum from the infection group were collected for etiological detection, and the composition of pathogenic bacteria was analyzed. The expression of miR-1323/IL-6 and IL-23/IL-17 were compared between the infected and uninfected group and among different prognostic subgroups. Receiver operating characteristic (ROC) curve analyzed the efficacy of miR-1323/IL-6 and IL-23/IL-17 in evaluating the short-term prognosis of patients with pulmonary infection after thoracoscopic radical lung cancer surgery.

RESULTS The relative level of miR-1323 in peripheral blood and serum levels of IL-6, IL-23 and IL-17 in the infected group were higher than those in uninfected group(P < 0.05). Totally 125 strains of pathogenic bacteria were detected in the sputum of 110 patients with pulmonary infection after surgery, of which gram-negative bacteria accounted for 73.60% (92/125), gram-positive bacteria 20.80% (26/125) and fungi 5.60% (7/125). Among the 110 patients with pulmonary infection after surgery, thirty-two had poor prognosis and 78 had good prognosis. The relative level of miR-1323 in peripheral blood and serum levels of IL-6, IL-23 and IL-17 in the poor prognosis group were higher than those in the good prognosis group, respectively (P < 0.05). The combined detection of miR-1323, IL-6, IL-23 and IL-17 on the prognosis of pulmonary infection after surgery had an area under the curve (AUC) of 0.944 with the sensitivity and specificity of 90.60% and 87.20%, respectively, which was higher than that of each index alone (P < 0.05).

CONCLUSION For lung infection after thoracoscopic radical lung cancer surgery, the pathogens are mostly gram-negative bacteria, and peripheral blood miR-1323 and serum IL-6, IL-23 and IL-17 express highly, and their combined detection has high predictive function on the prognosis.