Abstract:

Objective To study the changes on C-reactive protein(CRP) and clinical pulmonary infection score(CPIS) in aged patients with community acquired pneumonia(CAP) and the value in evaluation of the prognosis.Methods Ninety-eight elderly CAP cases were analysed retrospectively CRP,CPIS,white blood cell(WBC),neutrophil percentage(N),albumin(ALB) and prealbumin(PA) were measured on the 1st and the 7th days after admission.Data were compared with those of 30 aged patients without infection.CAP patients were divided into fatal group and surviaval group.ROC curve was used to determine the optimal limit value.Cases were divided into two groups by taking the decline of CRP less or more than 70% and CPIS less or more than 0.5 as the landmark.Statistical comparison was carried out on the results.Results On the 1st day after admission,the levels of CRP(77.87±69.97)mg/L in survival group and CRP(71.10±71.75)mg/L in the fatal group were much higher than that in the control group(4.30±3.91)mg/L,(P<0.01).The levels of CRP and CPIS were not significantly different between the fatal group and the survival group.After one-week treatment,compared with 1st day,the levels of CRP(22.44±22.83)mg/L and CPIS(2.34±2.15) declined significantly in the survival group.While the levels of CRP(61.28±40.37)mg/L and CPIS(6.04±2.23) were not significantly different in the fatal group.The levels of CRP and CPIS of the fatal group were much higher than those of the survival group(P<0.01).Through comparing AUC,the CRP decline ratio was better than that of the CPIS in predicting prognosis.According to the ROC curve,the optimal limit value in CRPdecline ratio was 70.33% and in CPIS 0.5 Using the two parameters together,the evaluation of treatment success had a specificity of82.4% and positive predictive value of 58.1%.In the regression analysis of the CAP cases,the regression equation is Y^= 0.551+0.064 CPIS2+0.064CPR2-0.205ALB1,the Coefficient is 0.603.Conclusion Dynamic observation of CRP and CPIS provides an important means in evaluating the prognosis of CAP in aged patients,especially when symptoms were atypical.It is recommended to use them jointly.

Key words: C-reactive Protein(CRP), clinical pulmonary infection score(CPIS), community acquired pneumonia(CAP), aged, prognosis