Clinical Evaluation Value Of Neutrophil-to-Lymphocyte Ratio In Severe Pneumonia

Objective:The pneumonia severity index(PSI)score and the CURB-65 score from the British thoracic society were used to determine the severity of Severe pneumonia(SP),the correlation between PSI score and CURB-65 score with white blood cell(WBC),neutrophil(NEU),neutrophil to lymphocyte ratio(NLR),c-reactive protein(CRP)and procalcitonin(PCT)were analyzed to evaluate the severity of severe pneumonia.The prediction value of NLR in the risk of death from severe pneumonia was also discussed.Methods:This study included 118 patients admitted with severe pneumonia to the Department of respiratory intensive care unit medicine,the first hospital of jilin university,from February 2015 to October 2019.Age,gender,length of stay,smoking history,associated underlying diseases(hypertension,diabetes,coronary heart disease,chronic obstructive pulmonary disease,cerebrovascular disease),prognostic survival time,WBC,NEU,lymphocyte count,CRP and PCT of all the selected patients were counted,and NLR were calculated.All patients were divided into 3 groups according to the PSI score(low risk group? 90 points,medium risk group 91-130 points,and high risk group > 130points),and 3 groups according to the CURB-65 score(group 1(0 or 1 riskfactor),group 2(2 risk factors),and group 3(3 or more risk factors)).SPSS22.0was used to compare the differences in WBC,NEU,NLR,CRP and PCT levels between groups,and to analyze the significance of NLR in two scoring systems for severe pneumonia.In addition,all patients according to 28 days survival condition were divided into survival group and death group,compared two groups of patients with general data characteristic,used the multivariate logistic regression analysis to screen the risk factors of death in patients with severe pneumonia,and draw the receiver-operating characteristic curve(ROC),further evaluation NLR predictive value in severe pneumonia risk of death.Results:(1)Comparison of results according to PSI,there was no significant difference in CRP between the low-risk group,the medium-risk group and the high-risk group(P>0.05),while there were significant differences in WBC,NEU,NLR and PCT(P< 0.05).NLR were the highest in the high-risk group,followed by the medium-risk group,with significant difference(P<0.05),suggesting that NLR was associated with the severity of severe pneumonia.(2)Comparison of results according to CURB-65,there were no significant differences in CRP and PCT between group 1(0 or 1 risk factor),group 2(2risk factors)and group 3(3 or more risk factors)(P> 0.05),while there were significant differences in WBC,NEU and NLR(P< 0.05),and the NLR was the highest in the group 3,suggesting that the NLR was associated with the severity of severe pneumonia.(3)Comparison of general data characteristics between the survival group and the death group,there were no significant differences between the two groups in gender,smoking history(P> 0.05).However,in terms of age,PSI,CURB-65,underlying diseases ? 2(hypertension,diabetes,coronary heart disease,chronic obstructive pulmonary disease,cerebral infarction),WBC,NEU,NLR,CRP and PCT,the death group was higher than the survival group,and the length of stay in the death group was less than that in the survival group,the difference was significant(P<0.05),suggesting that age,PSI,CURB-65,the length of stay,underlying diseases?2,WBC,NEU,NLR,CRP and PCT had a certain impact on the clinical outcome of severe pneumonia.(4)Analysis and comparison of etiology,look up to the etiology of 54 cases of 118 patients(the specific pathogen group),did not look up to the etiology of 64 cases(not clear the pathogen group),there were no significant differences in WBC,NEU,NLR,CRP and PCT between the two groups(P>0.05),suggesting that there was no correlation between NLR and etiology.(5)Risk factors for death in patients with severe pneumonia,logistic regression analysis was carried out on the risk factors affecting the death of patients with severe pneumonia,and the results showed that the length of stay,underlying diseases ? 2,NLR and PCT were independent risk factors affecting the prognosis of patients with severe pneumonia(P<0.05).(6)Predictive value analysis of risk factors on mortality risk of severe pneumonia patients,according to ROC curve analysis of various risk factors,the results showed that the area under the curve was the largest in the length of stay(AUC 0.783),followed by the area under the NLR(AUC 0.702).Compared with PCT,when the optimal truncation value of NLR was 13.61,the sensitivity was 53.3% and the specificity was 84.9%,while when the optimal truncation value of PCT was 0.42 ng/m L,the sensitivity was 73.3% and the specificity was 54.8%,suggesting that NLR had better predictive value for the risk of death in patients with severe pneumonia than PCT,and the NLR had higher specificity than PCT.Conclusion:(1)NLR is positively correlated with the severity of severe pneumonia,suggesting that the higher the NLR,the more serious the severity of severe pneumonia.(2)NLR,PCT,the length of stay and underlying diseases ? 2 are independent risk factors for the prognosis of severe pneumonia.(3)NLR is highly sensitive and specific in predicting the risk of death in patients with severe pneumonia.(4)The predictive value of NLR in predicting the death risk of patients with severe pneumonia was better than that of PCT,and the specificity of NLR was higher than that of PCT.