| Objective:To understand the overall situation of bloodstream infections in the young and old in our hospital,as well as clinical features,pathogen distribution and risk factors for infection.At the same time,the diagnostic value of PCT,IL-6,N,M,NLR,MLR,PLR in bloodstream infection and the differential diagnosis value of gram-positive and gram-negative pathogen infection were evaluated by drawing receiver operating curve.Methods:From January 2016 to December 2020,patients with bloodstream infection who met the inclusion criteria in the Second Affiliated Hospital of Kunming Medical University were selected as the research objects,namely bloodstream infection group,including blood culture positive bloodstream infection group and clinical diagnosis bloodstream infection group.Patients with negative blood culture and positive culture of sputum,throat swab,urine,stool or pus secretion were classified as local infection group;the patients without infection were divided into control group.The local infection group and the control group were collectively referred to as the non-bloodstream infection group.Patients’ basic clinical information including comorbid diseases,aggressive operation conditions,and laboratory test items including leukocytes,neutrophils,lymphocytes,monocytes,platelets,procalcitonin,and interleukin-6 could be collected from the hospital information system.We analyzed the risk factors of bloodstream infection by logistic regression and calculated the neutrophil to lymphocyte ratio,the monocyte to lymphocyte ratio,and the platelet to lymphocyte ratio.At the same time,the diagnostic value of PCT,IL-6,N,M,NLR,MLR,PLR in bloodstream infection and the differential diagnosis value of gram-positive and gram-negative pathogen infection were evaluated by drawing receiver operating curve.Results:1.There was no significant difference in PCT,IL-6,WBC,N,NLR levels between positive blood culture group and clinically diagnosed bloodstream infection group.The diagnostic efficacy of PCT,IL-6,WBC,N,NLR,PCT+IL-6+NLR in both groups were better.In the positive blood culture group,the area under curve(AUC)corresponding to the maximum Youden index of PCT was 0.87(95%CI:0.84-0.90),and the critical value was 0.17ng/ml;The AUC corresponding to the maximum Youden index of IL-6 was 0.87(95%CI:0.84-0.90),and the optimal cutoff value was 45.33 pg/ml;The area under the curve corresponding to the maximum Youden index of NLR was 0.79(95%CI:0.75-0.83),and the best cutoff value was 7.31×109/L;When combined with PCT+IL-6+NLR,AUC under maximum Youden index was 0.90(95%CI:0.87-0.93),sensitivity was 0.85 and specificity was 0.79.In the clinical diagnosis of bloodstream infection group,the AUC corresponding to the maximum Youden index of PCT was 0.90(95%CI:0-0.88),and the critical value was 0.22ng/ml;The AUC corresponding to the maximum Youden index of IL-6 was 0.89(95%CI:0-0.65),and the optimal cutoff value was 27.62pg/ml;The area under the curve corresponding to the maximum Youden index of NLR was 0.80(95%Cl:0-0.76),and the best cutoff value was 6.87×109/L.The AUC was 0.93(95%CI:0-0.90),the sensitivity was 0.87,and the specificity was 0.83.2.The AUC of IL-6 in distinguishing bloodstream infection with Gram-positive bacteria or Gram-negative bacteria was 0.70(95%CI:0.63-0.78),the sensitivity was 0.78,the specificity was 0.54;the AUC of combining PCT+IL-6 to distinguish bloodstream infection with G+ and G-increases,which was 0.71(95%CI:0.89-0.93),the sensitivity was 0.63,and the specificity was 0.73.3.The top three pathogens of gram-negative bacteria in the middle-aged group were as follows:Escherichia coli,Klebsiella pneumoniae,and Acinetobacter baumannii,and the top three pathogens of gram-negative bacteria in the elderly group were Escherichia coli,Klebsiella pneumoniae,and Pseudomonas aeruginosa Spores.The top three pathogens of Gram-positive bacteria in both groups were Staphylococcus aureus,Staphylococcus human and Staphylococcus epidermidis.4.In the elderly group,the main clinical departments for bloodstream infection patients were respiratory(38.04%),gastroenterology(11.96%),neurology(10.33%),Urology(8.70%),hepatobiliary(8.15%),nephrology(7.07%),cardiovascular(6.52%).In the young and middle-aged group,the main clinical departments of bloodstream infection patients were obstetrics,urology,respiratory,hepatobiliary surgery,rehabilitation,and nephrology,with the proportion of 20.63%,15.00%,14.38%,11.25%,7.50%,6.88%,respectively.In the Middle-aged group,patients with bloodstream infection were mainly the distribution of clinical departments were obstetrics(20.63%),urology(15.00%),respiratory(14.38%),Hepatobiliary(11.25%),reha-bilitation(7.50%),nephrology(6.88%).5.Logistic regression results showed that surgical history,cardiac insufficiency,liver injury,respiratory tract infection,urinary tract infection,hypoproteinemia,pleural effusion,hypertension,and diabetes were risk factors for BSI in the elderly group.Liver injury,renal insufficiency,urinary tract infection,hypoproteinemia,and pleural effusion were risk factors for BSI in the middle-aged group.Conclusions:1.In the blood culture positive group,the AUC corresponding to the maximum Youden index of PCT+IL6+NLR was 0.90,the sensitivity was 0.85,and the specificity was 0.79,which was higher than that of single index;In the clinical diagnosis of bloodstream infection patients,the AUC of combining PCT+IL6+NLR was 0.93,sensitivity was 0.87,specificity was 0.83.2.The AUC of combining PCT+IL-6 in distinguishing bloodstream infection with Gram-positive bacteria and Gram-negative bacteria was 0.71,the sensitivity was 0.63,and the specificity was 0.73.3.In the elderly group and middle-aged group,the main clinical departments of bloodstream infection patients were respiratory department and urology department.In addition,the main clinical departments for bloodstream infection patients in the elderly group also included gastroenterology,nephrology and cardiovascular medicine.The main clinical departments for bloodstream infection patients in the young were obstetrics.Therefore,strengthening the department management can greatly reduce the prevalence of BSI.4.The risk factors of bloodstream infection in the elderly were respiratory tract infection and hypoproteinemia;the risk factors of bloodstream infection in the young were urinary tract infection and renal insufficiency.Therefore,we should emphasize that BSI risk factors of different age groups are different.We should take relevant measures to reduce the incidence rate of BSI. |
