Relations between inflammation biomarkers and CT pulmonary artery obstruction index in patients with pulmonary embolism

Objective To investigate the relationships between white blood cell (WBC), neutrophils, lymphocytes, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio and serum IL-6 levels with pulmonary artery obstruction index (PAOI) in pulmonary embolism (PE) patients before and after short term treatment. Methods A prospective study was conducted on the PE patients first-diagnosed by computed tomographic pulmonary angiography in 3 hospitals from June 2015 to February 2017.The WBC, neutrophils, platelets, lymphocytes, neutrophil to lymphocyte radio (NLR), platelet to lymphocyte radio and serum IL-6 levels were examined pre-treatment and post-treatment on the 14th day.The relationships of these biomarkers with PAOI were analyzed pre-treatment and post-treatment on the 14th day. Results A total of 47 PE patients were enrolled from 3 hospitals.The PAOI was positively correlated with WBC, neutrophils, NLR, IL-6 pre-treatment (all P<0.05). The PAOI was positively correlated with IL-6 post-treatment (r=0.498, P=0.000). The varied rate of PAOI pre-and post-treatment were negatively correlated with NLR pre-treatment (r=-0.352, P=0.015), positively correlated with lymphocytes pre-treatment (r=0.335, P=0.021). Conclusions The WBC, neutrophils, NLR and IL-6 levels have correlations with PAOI, especially the IL-6 has closer correlation with PAOI, which could predict the degree of pulmonary artery obstruction better.The lower NLR and higher lymphocytes, the more significant of the embolus dissolution effect, they all have a certain clinical significance in predicting the degree of pulmonary embolus dissolution. Key words: Pulmonary embolism; Pulmonary artery obstruction index; White blood cell; Neutrophil to lymphocyte radio; Lnterleukin-6