Objective To analyze the species distribution and resistance of the pathogens isolated fromblood cultures of the patients in intensive care unit ( ICU) , and provide a basis for prevention and control of bloodstream infections in critically ill patients. Methods The data of blood cultures of the patients in ICUduring January 2009 to December 2011 was investigated retrospectively.Results In the last 3 years, positive rate of blood cultures of ICU patients was 15. 4% , 15. 7% , and 17. 6% respectively. Among the isolates, Gram-positive bacteria were predominant ( 52. 3% ) , followed in order by gram-negative bacteria ( 33. 1% ) and fungi ( 14. 7% ) . Aerobe and facultative anaerobe were the predominant bacterial isolates ( 99. 7% ) . Enterococcus faeciumand Staphylococcus spp. were the most common gram-positive bacteria, and 4. 5% of E. faecium isolates were resistant to vancomycin. Rate of methicillin-resistance for S. aureus and S. epidermidis was 73. 5% and 93. 7% respectively. In terms of gram-negative bacteria, Acinetobacter calcoaceticus- A. baumannii complex were the leading species, 96. 9% of the isolates had multi-drug resistance and 14. 1% of the isolates had extra-drug resistance. Klebsiella pneumonia and Escherichia coli isolates were less frequently isolated and those producing extended spectrum beta-lactamases accou ted for 70. 3% and 80. 0% of the isolates respectively. Candida spp. was the most common fungi isolates ( 96. 7% )with an annual change of species distribution and declining susceptibility to azoles.Conclusions Gram-positive bacteria should be the major target for prevention and control of bloodstream infections in critically ill patients. Whereas, more attention should be paid to the infection caused by candida spp. and multidrug resistant gram-negative bacteria.
中心静脉置管是现代重症医学救治危重患者的常用方法, 目前应用十分广泛。尽管这些导管提供了必要的血管通路, 但也将患者置于局部和全身性感染并发症的危险之中, 增加了感染的发生率, 并使导管相关性血流感染( catheter-related bloodstream infections, CRBSI) 更为常见, 明显延长了ICU 住院时间并增加了医疗费用。本文就近年来CRBSI 的发病机制、微生物学、诊断及治疗, 尤其是如何根据病原体对CRBSI 进行治疗做一概述。
Objective To explore the vascular access infection (VAI) incidence of hemodialysis patients during the the maximum spread of the COVID-19 epidemic (epidemic period) compared with the corresponding period with no local cases of COVID-19 (control period). Methods A single-center, retrospective study was carried out. Adult patients who underwent hemodialysis at the Department of Blood Purification Center, the Affiliated Hospital of Xuzhou Medical University during the epidemic period between December 7, 2022 and February 23, 2023 and the control period between December 7, 2020 and February 23, 2021 were selected. The incidence of local access site infection (LASI) and access related bloodstream infection (ARBSI) in included patients were observed and compared. ResultsA total of 1 401 patients were included. Among them, there were 737 cases during the epidemic period and 664 cases during the control period. There was no statistically significant difference in the age, gender, and duration of catheterization among patients of different periods and pathway types (P>0.05). There was no statistically significant difference in the occurrence of LASI between the epidemic period and the control period (χ2=1.800, P=1.180). There was a statistically significant difference in the occurrence of ARBSI between the epidemic period and the control period [χ2=4.610, relative risk (RR)=2.575, 95% confidence interval (CI) (1.053, 6.298), P=0.032]. There was no statistically significant difference in the incidence of LASI and ARBSI at different stages in patients with arteriovenous fistula and unnel-cuffed catheters (TCC) (P＞0.05). There were statistically significant differences in the incidence of LASI [χ2=4.898, RR=3.832, 95%CI (1.058, 13.885), P=0.027] and ARBSI [χ2=7.150, RR=4.684, 95%CI (1.333, 16.460), P=0.005] among non cuffed catheters (NCC) patients at different stages. TCC patients might experience LASI (P<0.05) during the epidemic period and ARBSI (P<0.05) during the control period compared with the arteriovenous fistula patients; both central venous catheterization and NCC patients might experience LASI and ARBSI during the control period (P<0.05). Conclusion Targeting COVID-19 prevention may be associated with the reduction of vascular access infection in hemodialysis patients, in particular in NCC patients.
Objective To evaluate the basic performance and clinical application value of nanopore sequencing, in order to provide new ideas for the rapid detection of clinical etiology. Methods From December 2021 to May 2022, blood samples from inpatients suspected of bloodstream infection in Renmin Hospital of Wuhan University were collected, and the nanopore sequencing platform and blood culture method were used to simultaneously identify the pathogenic bacteria in the blood samples of the selected patients, and identify the pathogenic bacteria in the blood samples of the selected patients. The basic performance and clinical utility of nanopore sequencing were evaluated. Results A total of 251 patients were included, and 119 patients (47.4%) were found to have pathogens by nanopore sequencing, which was higher than that of 23 patients (9.2%) by blood culture (χ2=79.167, P<0.001). The results of the two methods are not consistent (kappa=0.052, P=0.175). Nanopore sequencing has a certain missed detection rate. In terms of the types of pathogenic bacteria detected, 47 bacteria and 15 fungi were detected by nanopore sequencing. Conclusion Compared with blood culture, nanopore sequencing has a higher detection rate and more types of pathogens. This technology has obvious advantages in the rapid diagnosis of bloodstream infection pathogens.
Objective To analyze the characteristics of pathogens causing bloodstream infection (BSI) after cardiovascular surgery, and provide instructions for prevention and treatment of such kind of disease. Methods A retrospective investigation of clinical and pathogenic data of the patients suffering from BSI after cardiovascular surgery in West China Hospital of Sichuan University from January 2015 to December 2016 was performed. There were 61 patients with 36 males and 25 females at average age of 48.2±17.1 years. A percentage of 65.6% (40/61) of the underlying diseases was rheumatic heart disease. Results Sixty-five strains were isolated from the blood culture specimens of the 61 patients. Gram-positive bacteria, gram-negative bacteria and fungi isolates accounted for 56.9% (37/65), 35.4% (23/65), and 7.7% (5/65), respectively. Among these isolates, Streptococcus spp. was predominant (19/65, 29.2%), followed by Staphylococcus epidermidis (8/65, 12.3%), Staphylococcus aureus (6/65, 9.2%), Acinetobacter calcoaceticus- A. baumannii (5/65, 7.7%) and Escherichia coli (5/65, 7.7%). The resistance rate of Streptococcus spp. to erythromycin and clindamycin was 73.4% (14/19) and 63.2% (12/19), while its resistance to cefepime, vancomycin or linezolid was not observed. Staphylococcus spp. showed the resistance rate of 71.4% (10/14) to oxacillin. All of A. calcoaceticus-A. baumannii isolates were multidrug resistant (5/5, 100.0%), and 80.0% (4/5) of them were resistant to imipenem. The isolates producing extended spectrum beta-lactamase accounted for 80.0% (4/5) of E. coli. Conclusion Streptococcus spp. was the common pathogen causing BSI after cardiovascular surgery. Staphylococcus spp. and gram-negative bacilli show high resistance.
ObjectiveTo explore the prognostic risk factors for patients with gram positive coccus bloodstream infections. MethodsBy retrospective analysis, 93 patients with gram positive coccus bloodstream infections were recruited from the China-Japan Friendship Hospital during January 2013 to April 2015.According to the 28-day survival situation, the patients were divided into a survival group and a death group.The clinical data including basic diseases and invasive operation were collected.Logistic regression analysis was used to evaluate the risk factors for predicting prognosis. ResultsThe albumin concentration in the death group was lower than that in the survival group (P < 0.05).The D-Dimer concentration, APACHEⅡscores, the percentage of patients with mechanical ventilation, and the percentage of patients with deep venous cannels in the death group were all higher than those in the survival group (P < 0.05).The percentages with diabetes mellitus, surgery, tumor, renal failure in the patients with enterococcus bloodstream infections were much higher than those patients with other gram positive coccus bloodstream infections (P < 0.05), but were not different with those patients with Staphylococcus aureus bloodstream infection (P > 0.05).The APACHEⅡscore and albumin concentration had statistical significance for predicting the 28-day and 90-day mortality.The area under the receiver operating characteristic (ROC) curve was 0.768 and 0.775.If using APACHEⅡscore > 22.5 as cut off value for predicting death in 28 days, the sensitivity was 70.0%, and the specificity was 81.2%.If Using albumin concentration < 32.5 g/L as a cutoff value for predicting death in 28 days, the sensitivity was 55.3%, and the specificity was 86.7%. The logistic multifactor analysis revealed only the lower albumin concentration was an independent prognostic factor for 28-day mortality of the patients with gram positive coccus bloodstream infections (P < 0.05). ConclusionsThe patients with diabetes mellitus, surgery, tumor, and renal failure need to be cautious of enterococcus bloodstream infection.The low albumin concentration suggests a poor prognosis in patients with gram positive coccus bloodstream infections.
Objective To explore the overall outcome and its factors of patients with carbapenem-resistant Pseudomonas aeruginosa bloodstream infection (CRPA-BSI). Methods A single-center, retrospective cohort study was carried out. The demographic and clinical data of all emergency patients and inpatients in West China Hospital of Sichuan University from 2017 to 2021 were collected. Firstly, the prognosis of patients with CRPA-BSI was compared with those with carbapenem-sensitive Pseudomonas aeruginosa bloodstream infection (CSPA-BSI). Then Cox regression was used to analyze the factors affecting the prognosis of CRPA-BSI patients. Results A total of 53 patients with CRPA-BSI and 175 patients with CSPA-BSI were enrolled, and they were 1∶1 matched according to the age-adjusted Charlson Comorbidity Index (aCCI) to control for confounding factors. When aCCI was similar, the incidence of poor prognosis in CRPA-BSI patients was significantly higher than that in CSPA-BSI patients [41.5% vs. 18.9%; relative risk=2.20, 95% confidence interval (CI) (1.16, 4.19), P=0.011]. The median length of hospital stay in the CRPA-BSI group was 3 d longer than that in the CSPA-BSI group but the difference was not statistically significant (29 vs. 26 d, P=0.388). With regard to prognostic factors, univariate Cox regression analyses showed that the highest temperature ≤39℃ (P=0.014), hepatobiliary and pancreatic diseases (P=0.011), days of central venous catheterization (P=0.025), days of indwelling urinary catheters (P=0.037), adjustment of medication duration according to drug sensitivity results (P=0.015) and Pitt bacteremia score (P=0.007) were related to the poor prognosis of CRPA-BSI patients. Multiple Cox regression analysis showed that hepatobiliary and pancreatic disease [hazard ratio (HR)=3.434, 95%CI (1.271, 9.276), P=0.015] and Pitt bacteremia score [HR=1.264, 95%CI (1.057, 1.510), P=0.010] were independently associated with poor outcome in CRPA-BSI patients. Conclusions The prognosis of CRPA-BSI patients is worsen than that of CSPA-BSI patients. Hepatobiliary and pancreatic diseases significantly increase the risk of poor outcome in CRPA-BSI patients. Pitt bacteremia score is a predictor of prognosis in patients with CRPA-BSI.