Xing Tang, Yan Xie, Jingkang He#


Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215006, Jiangsu Province, P. R. China


We aimed to study pathogen distribution in patients with ventilator-associated pneumonia (VAP) and diagnostic values of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Sixty-eight VAP patients treated from June 2016 to February 2018 were enrolled as an observation group and subdivided into a survival group (n=50) and a death group (n=18) according to 28th-day prognosis. Thirty VAP-free patients receiving ventilator therapy were included as a control group. The purulent fluid or sputum was collected. Venous blood was taken at intubation (T0), 24 h (T1) and 120 h (T2) after diagnosis. The correlation between NLR and PLR was analyzed, and their evaluation values for prognosis were confirmed by ROC analysis. A total of 358 microbial strains were isolated. Gram-negative bacteria (222) were the main pathogens, accounting for 35.64%. Gram-positive bacteria (124) accounted for 34.64%, and 12 fungal strains were detected (3.35%). At T1 and T2, NLR and PLR of observation group significantly exceeded those of control group, and the values of death group significantly surpassed those of survival group (P<0.05). NLR was significantly positively correlated with PLR upon diagnosis (r=0. 362, P=0.008, P<0.05). AUC of NLR at T1 was 0.756, with the sensitivity and specificity of 71.2% and 85.6%, respectively (P=0.015). AUC of PLR was 0.832, with the sensitivity and specificity of 79.54% and 86.2%, respectively (P=0.028). Gram-positive bacteria were the dominant pathogens in VAP patients. NLR and PLR are potentially eligible indices for timely severity assessment and prognosis determination. 


ventilator-associated pneumonia, pathogen distribution, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio.