The Effect Of Lymphocyte Count On The Prognosis Evaluation Of Community Acquired Pneumonia

Purpose To explore the effect of lymphocyte count on the prognosis evaluation of patients with community acquired pneumonia(CAP).Method In this paper, the clinical materials of 273 CAP patients accepted by the Respiratory Medicine Department and ICU of General Hospital of Tianjin Medical University from June, 2012 to June, 2015 were included, retrospective case-control method was conducted, and the patients were divided into 2 groups(i.e. Survival group with 219 cases and death group with 54 cases) according to their prognosis. The lymphocyte count, blood white cell count(WBC) and c-reactive protein(CRP) and the clinical pulmonary infection score(CPIS) of the patients were detected and recorded respectively at 1 day and 5 days(including 5 days) after treatment. Software SPSS 17.0 was adopted to analyze the differences of each variable between 2 groups and the dynamic change before and after the treatment. The correlation between lymphocyte count and CPIS change at the corresponding time point was analyzed. The correlation between lymphocyte count and the change of WBC and CRP at the corresponding time point was analyzed. And the correlation between lymphocyte count, WBC, CRP and prognosis, disease severity was further analyzed. Then the independent risk factors of lymphocyte count, WBC and CRP to the determination of CAP prognosis were screened by multifactor logistic regression analysis. The ROC curve to determine the prognosis by lymphocyte count. WBC and CRP were drawn. Then Z test was adopted to compare the space of prognosis ROC curve related to the lymphocyte count at the corresponding time point.Result There's no statistical significance in the difference of the base materials(age, gender, length of stay and so on) between survival group and death group. The difference of lymphocyte count, WBC and CPIS on admission between survival group and death group has no statistical significance. On 5 days after treatment, the lymphocyte count of the survival group was higher than that of the death group, while CRP and CPIS were lower than the death group, and there're statistical differences between 2 groups. There's no statistical difference in WBS between 2 groups. Comparing the result on 5 days after treatment with on admission, the lymphocyte count of the survival group increased, but without statistical difference, and there's no statistical difference in WBC change, while blood CRP and CPIS declined after treatment with statistical difference. However, there's no statistical difference on lymphocyte count, WBC, CRP and CPIS in death group. The lymphocyte count of patients was negative related to CPIS at the corresponding time point for 1 day and 5 days after the treatment. The lymphocyte count of patients was negative related to CRP at the corresponding time point for 1 day and 5 days after the treatment, while presented no obvious correlation with the WBC at the corresponding time point for 1 day and 5 days after the treatment. The CRP of patients was positively related to CPIS at the corresponding time point for 1 day and 5 days after the treatment, and WBC was not related to CPIS at the corresponding time point. The prognosis of patients was treated as the dependent variable(death as 1 and survival as o), and lymphocyte count, WBC and CRP were treated as independent variables to conduct independent variable. The result demonstrated that lymphocyte count was the only independent risk factor among all the independent variables to determine prognosis. Regarding to the lymphocyte count, WBC and CRP after admission to determine prognosis in ROC curve, the area of lymphocyte count on 1 day and 5 days after treatment under the ROC curve was significantly greater than 0.5, and the area of CPIS on 5 days after treatment under the ROC curve was significantly greater than 0.5(in both cases, P<0.05). Compared with the area of lymphocyte count under the ROC curve, the area of WBC, CRP on 1 day and 5 days after treatment under the ROC curve was significantly smaller than that of lymphocyte count at the corresponding time point(in all cases, P<0.05). The area of CPIS on 1 day after treatment under the ROC curve was significantly smaller than that of lymphocyte count at the corresponding time point(P<0.05), and there's no statistical difference between 2 curves on 5 days after treatment(P>0.05).Conclusion Dynamic detection of lymphocyte count change can reflect the disease severity and prognosis of the patients which could serve as an effective indicator to monitor the disease in the treatment of pneumonia, thus is of vital clinical indicating meaning to evaluate the prognosis of the elder patients with community acquired pneumonia(CAP), especially for those who have atypical clinical manifestations.