Application Of Neutrophil/Lymphocyte Ratio In The Differential Diagnosis Of Bacterial Community-acquired Pneumonia And Tuberculosis

Objective:Tuberculosis and the differential diagnosis of bacterial community acquired pneumonia has always been a problem in clinical physicians,both in the early onset is said to have similar clinical manifestations,imaging can’t distinguish between the two diseases completely,and sputum smear check acid fast bacilli positive rate is low,it has brought the early correct diagnosis and treatment of disease of certain obstacles.In this study,the neutrophils/lymphocytes ratio of patients with bacterial community-acquired pneumonia and PTB was compared to analyze its differential value in the two diseases,so as to provide some scientific basis for the early and correct diagnosis of the two diseases in clinical practice.Methods:Retrospectively collected 176 and 189 patients with PTB and bacterial CAP,respectively,who were diagnosed in Anshun People’s Hospital from January 2019 to December 2019.All patients were older than 18 years old.The differences in general information,clinical symptoms,combined diseases,chest imaging features and serological indexes between the two groups were compared and analyzed.Chi-square test and Fisher’s exact probability test were used to compare the counting data.First,the measurement data were tested for normality and homogeneity of variance.The measurement data conforming to the normal distribution and homogeneity of variance were analyzed by the t-test of two groups of independent samples,and the comparison analysis was conducted by the rank sum test for non-normal distribution or heterogeneity of variance.Receiver operator characteristic curve(ROC curve)was used to evaluate the discriminative efficacy of each laboratory indicator.Results:General information: 176 patients with PTB,including 115 males and 61 females,with a median age of 54 years;There were 189 CAP patients,including 128 males and 61 females,with a median age of 54 years.There was no statistical significance in age and sex between 2 groups(P>0.05).There were 97 cases(55.1%)in the PTB group and 84 cases(44.4%)in the CAP group with a course of disease longer than two weeks by the time of admission,and the difference between the two groups was statistically significant(P<0.05).Clinical symptoms: patients in PTB group were more prone to hemoptysis,shortness of breath,chest tightness,low fever and fever,with statistical significance(P<0.05).Complicating diseases: The number of patients with hypertension and coronary heart disease in the CAP group was more than that in the PTB group,while the number of patients with previous tuberculosis history was more in the PTB group,and the difference between the two groups was statistically significant(P<0.05).Chest imaging features: In the PTB group,there were 146,13,16,1 patients with lesions involving both lungs,only the left lung,only the right lung,and no obvious abnormalities in the imaging morphology of the lungs.In the CAP group,122 cases were involved in both lungs,20 cases were involved in the left lung,38 cases were involved in the right lung,and the lung imaging morphology showed no obvious abnormalities,respectively.Patients in the PTB group had more lesions involving both lungs than those in the CAP group,and the proportion of lesions involving only the right lung or chest imaging without obvious abnormalities in the CAP group was significantly higher than that in the PTB group(P<0.05).The proportion of pulmonary imaging morphology of PTB patients with flocculent high-density shadow and pleural effusion was lower than that of CAP group,and the proportion of high-density shadow with cable-like and nodular shadow was higher than that of CAP group,with statistical significance(P<0.05).Hematological indicators: WBC,MPV,CRP and NLR in CAP group were significantly higher than those in PTB group,and ESR was significantly lower than that in PTB group,with statistical significance(P<0.05).By drawing the ROC curve,the AUC of the combined diagnosis of five laboratory indicators was the largest,which was 0.796(P<0.05).The optimal Cut-off value for the identification of the two groups was 0.633,with a sensitivity of 73.2% and a specificity of 73.2%.Among the single laboratory indicators,NLR had the best discriminative efficacy.The AUC of NLR was 0.757(P<0.05),and the best Cut-off value of NLR was 6.036,with a sensitivity of 50.8% and specificity of 86.9%.Conclusions:1.The NLR level of PTB patients was significantly lower than that of CAP patients,and NLR<6.036 was more supportive of the diagnosis of PTB.2.NLR may be of value in the differential diagnosis of atypical PTB(acute onset,accompanied by high fever above 38℃,atypical lesion site and chest imaging features)and bacterial CAP.3.NLR plays a certain role in the clinical differential diagnosis of bacterial CAP patients with previous history of PTB and current onset with hemoptysis from PTB patients.4.NLR combined with WBC,MPV,CRP and ESR has greater efficacy in the differential diagnosis of PTB and bacterial CAP.