Clinical Study On The Assessment Of The Severity And Pathogen Diagnosis Of Community-acquired Pneumonia

Objective:Assessment of the severity of CAP in time and reasonable treatment with antimicrobial are vital for a satisfactory clinical outcome and cutting costs.The retrospective study is divided into two parts: part one compared the predictive accuracy of the acute physiology and chronic health evaluation ?(APACHE ?),the pneumonia severity index scores(PSI scores),the CURB-65 scores,and serum procalcitonin concentration in prediction of prognosis for inpatients with CAP.Then select the best one and screen risk factors that influence deterioration.Part two: On the basis of the optimal method,compare the level of serum PCT of CAP patients in different severity,and compare the change of PCT in different pathogen infection.Methods:Part one: The patients of CAP who were admitted in the Department of Respiratory Medicine of First Hospital of Shanxi Medical University University between January 2015 and December 2016 were studied.Calculated the APACHE??CURB-65 and PSI scores based on the relevant data within 24 hours of their admission.The end point of this study was the clinical outcome of hospitalization(recovery,improvement,exacerbation or death).Receiver operating characteristic(ROC)curve analysis and binary logistic regression models were used to assess the ability of these methods and determine the boundary value,to screen risk factors that influence the outcome of CAP patients.Part two: From above cases,we selected 153 patients with sputum culture results,and divided them into two groups based on whether the acute physiology and chronic health evaluation ?(APACHE?)scores were greater than 11 points.Nonparametric comparisons between the two groups weredone by Wilcoxon rank sum test.Steel.Dwass test was applied to compare PCT levels of different pathogens.Results:235 CAP patients were enrolled with 146 males and 89 females at an average age of(60.4±18.1).All patients were divided into 2 groups: improving recovery group205 cases,and deteriorating group,30 cases.The rank of areas under the ROC curve,predicting the deterioration and death risk of CAP,from big to small were APACHE?(0.889),PSI(0.850),CURB-65(0.789),and PCT(0.720).Over 11 points of APACHE and over 91 of PSI were optimal cut-off values for the prognostic assessment.Moreover,the clinical outcome was served as dependent variable,APACHE ? scores ? pleural effusion ? the level of PCT and CRP were set as dependent variables.The logistic regression analysis revealed that APACHE ?scores and PCT levels were independent risk factors of deterioration and death in CAP patients,they fit well.Part two: We selected 153 CAP patients which included 103 males and 50 females at an average age of(63.97±17.40).A total of 153 pathogenic bacteria were detected,including 63 strains of G+ bacteria and 90 strains of Gbacteria.There were 85 cases that scored more than 11 points.Serum PCT levels were not identical when the pathogens isolated from CAP patients were different.The serum PCT level of the Acinetobacter baumannii and Enterobacteriaceae were higher than(para)Haemophilus influenzae.But the overlap between the different pathogens was large and some serum PCT levels were normal.Conclusion:The better predictability of clinic outcome of CAP was APACHE?,PSI,CURB-65,and PCT respectively in order,while the APACHE ?scores and PCT concentration were independent risk factors for exacerbation and mortality in CAP patients.The predictive ability of a single PCT measurement is limited.The combination of them may increases specificity,but reduces sensitivity more.The more serious the condition of CAP patients,the more obvious the increase of serumPCT levels.Serum PCT levels are of very limited value in the initial identification of community-acquired pneumonia-infecting pathogens.