Risk Factors Of Pancreatic Infection Secondary To Severe Acute Pancreatitis And The Distribution Of Common Pathogenic Bacteria

Objective:To explore the risk factors,the distribution of pathogenic bacteria and the relationship between common clinical treatment measures and pancreatic infection in patients with severe acute pancreatitis(SAP),so as to provide a reference basis for predicting and reducing the occurrence of secondary infection in patients with SAP.Method:Collected and analyzed retrospectively the First Clinical Hospital of Jilin University between January 2014 and December 2019,a total of 144 patients with diagnosis of the basic information of the hospitalized patients with SAP(age,gender,time from onset to admission),etiology,past history,complications after admission,Laboratory data,imaging data,clinical grade and treatment measures,such as disease outcome clinical data.Patients were divided into the infected group and the non-infected group according to the presence or absence of pancreatic infection,and the statistical analysis was conducted by SPSS 21.0software.The rate of use(composition ratio)of enumeration data indicated that Pearson chi-square or Fisher's exact probability method was used for comparison between the two groups.The shapiro-wilk method was used to test the normality of the measurement data.The data conforming to the normal distribution were expressed as mean ± standard deviation((?)±S).The independent sample t test was used for the comparison between the twogroups.Data that did not conform to normal distribution were represented by median(inter-quartile range),and mann-whitney U test was used for comparison between the two groups.Variables with statistical differences were analyzed by binary multivariate Logistic stepwise regression to identify independent risk factors,and odds ratio(OR)and 95%confidence interval were calculated to identify independent risk factors.The selectedcontinuous independent risk factors using the ROC curve to calculate the area under the curve(AUC),sensitivity,specificity and youden index.The cutoff value is the value of the variable with the largest youden index.P<0.05 was considered statistically significant.Result:(1)A total of 144 SAP patients were included in this study,including 55 in the infected group(38.2%)and 89 in the non-infected group(61.8%).The incidence of pancreatic infection was 38.2%.A total of 24 people died,with a mortality rate of 16.7%.Among them,14 people died in the infected group,with a mortality rate of 25.5%,and 10 people died in the non-infected group,with a mortality rate of 11.2%.(2)The results of single factor analysis show that:sepsis(P=0.000),pulmonary infection(P=0.016),persistent multi-organ failure(P=0.015),intestinal dysfunction time >7 days(P=0.029),intraabdominal pressure(IAP)>15mmHg(P=0.005),hematopoietic volume(HCT)(P=0.02),c-reactive protein(CRP)(P=0.02),procalcitonin(PCT)(P=0.004),lactate dehydrogenase(LDH)(P=0.012),abdominal CT showed necrosis(P=0.005),abdominal CT showed bleeding(P =0.015),abdominal drainage >7 days(P =0.033),the infected group was higher than the non-infected group,there was a statistical difference between the two groups.Albumin(ALB)(P=0.024)and fasting time ?3 days(P=0.029)were lower in the infected group than in the non-infected group,and there was a statistical difference between the two groups.(3)The factors with statistical differences in univariate analysis were used as independent variables,and the secondary pancreatic infection was used as dependent variables for multivariate Logistic stepwise regression analysis.The results showed that HCT(OR=1.108,P=0.006),CRP(OR=1.006,P=0.021),PCT(OR=1.017,P=0.019),ALB(OR=0.917,P=0.017),sepsis(OR=10.085,P=0.002),IAP>15mmHg(OR=2.922,P=0.014)were independent risk factors for pancreatic infection secondary to SAP.(4)The continuous variables HCT,CRP,PCT and ALB with statistical significance were used to plot the ROC curve.The results showed that the AUC value of HCT was 0.647,the cutoff value was 44.75%,the sensitivity was 56.4%,the specificity was 67.4%,and theyouden index was 0.238.The AUC value of CRP was 0.650,the cutoff value was 236.59mg/L,the sensitivity was 49.1%,the specificity was 82%,and the youden index was0.311.The AUC value of PCT was 0.643,the cutoff value was 5.77ng/ml,the sensitivity was54.5%,the specificity was 70.8%,and the youden index was 0.253.The AUC value of ALB was 0.606,the cutoff value was 28.55 g/L,the sensitivity was 54.5%,the specificity was65.2%,and the youden index was 0.197.The AUC value of the above indicators in the combined diagnosis was 0.754,the sensitivity was 58.2%,the specificity was 84.3%,and the youden index was 0.425.(5)Common pathogenic bacteria of pancreatic infection secondary to SAP: a total of 50 pathogenic bacteria were detected in the infection group in this study,among which 28 were gram-negative bacteria,accounting for 56%;17 were gram-positive bacteria,accounting for34%;5 were fungi,accounting for 10%.Among them,16 strains of pathogenic bacteria were detected within 4 weeks after onset,including 13 strains of gram-negative bacteria,2 strains of gram-positive bacteria and 1 strain of fungus.A total of 34 strains of pathogenic bacteria were detected 4 weeks after onset,including 15 strains of gram-negative bacteria,15 strains of gram-positive bacteria and 4 strains of fungi.Conclution:(1)In this study,the six variables of HCT,CRP,PCT,ALB,sepsis and IAP>15mmHg were considered as independent risk factors for pancreatic infection secondary to SAP,among which HCT,CRP,PCT,sepsis and IAP>15mmHg were positively correlated with secondary pancreatic infection and negatively correlated with ALB,which were protective factors.Monitoring the above changes and timely correction during the hospitalization of SAP patients is helpful to prevent the occurrence of pancreatic infection secondary to SAP and improve the prognosis of patients.(2)The combination of HCT,CRP,PCT and ALB was more accurate in predicting pancreatic infection than that of single factor.(3)The pathogenic bacteria of pancreatic infection were mainly gram-negative bacteria,and gram-positive bacteria and fungal infections mostly occurred in the late course ofdisease(>4 weeks).Clinical empirical application of antibiotics should be combined with drug sensitivity results to adjust the selection of antibiotics.