ObjectiveTo analyze the clinical characteristics, risk factors, and drug resistance of pathogenic bacteria in patients with blood stream infections (BSI) after orthopedic surgery, so as to provide reference and basis for clinical diagnosis and treatment.MethodsA retrospective analysis was made on the clinical data of 6 348 orthopedic patients admitted for surgery between January 2017 and December 2019. There were 3 598 males and 2 750 females. Their age ranged from 18 to 98 years, with an average of 66 years. The data of patients were collected, and the risk factors of BSI were analyzed by univariate analysis and logistic regression analysis. The distribution of BSI pathogenic bacteria, the results of drug sensitivity test, the incidence of BSI in patients after orthopedic surgery in different years, and the common sites of BSI secondary infection were summarized.ResultsBSI occurred in 106 (1.67%) of 6 348 patients after orthopedic surgery. There were 71 cases (66.98%) of secondary infection. The mortality of postoperative BSI patients was 1.89%, and the difference was significant when compared with that of non-postoperative BSI patients (0.24%) (χ2=5.313, P=0.021). The incidences of BSI in 2017, 2018, and 2019 were 1.18%, 1.53%, and 2.17%, respectively, showing an increasing trend year by year (trend χ2=6.610, P=0.037). Statistical analysis showed that the independent risk factors for BSI after orthopedic surgery (P<0.05) included the trauma, length of hospital stay≥14 days, emergency surgery, postoperative leukocyte counting<4×109/L, level of hemoglobin≤90 g/L, albumin≤30 g/L, the time of indwelling ureter>24 hours, use of deep vein catheter insertion, and merging other site infection. Blood culture showed 56 strains (52.83%) of Gram-positive bacteria, 47 strains (44.34%) of Gram-negative bacteria, and 3 strains (2.83%) of fungi. The top three pathogenic bacteria were coagulase negative Staphylococci (CNS; 36 strains, 33.96%), Escherichia coli (16 strains, 15.09%), and Staphylococcus aureus (15 strains, 14.15%). The detection rates of extended-spectum β-lactamases producing strains of Escherichia coli and Klebsiella pneumoniae were 56.25% (9/16) and 44.44% (4/9), respectively. The detection rates of methicillin-resistant strains in Staphylococcus aureus and CNS were 46.67% (7/15) and 72.22% (26/36), respectively.ConclusionPostoperative BSI in orthopedic patients is caused by multiple factors. Preventive measures should be taken according to related risk factors and perioperative risk assessment should be strengthened. Staphylococcus and Escherichia coli are the most common pathogenic bacteria in BSI after orthopedic surgery. The infection rate and drug-resistant bacteria are increasing year by year. Therefore, drug resistance monitoring should be strengthened.
Objective To investigate the species distribution and antibiotic resistance among the bloodstream infections in intensive care unit ( ICU) . Methods A retrospective analysis was performed to review the microbiological and susceptibility test data of all bloodstream infections in ICU from January 2004 to September 2009. The patterns of antibiotic resistance among the top five bacteria were compared. Results 89 cases of bloodstream infection were detected with 112 strains, including 55 Gram-positive ( G+ ) bacteria( 49. 1% ) , 55 Gram-negative ( G- ) bacteria ( 49. 1% ) , and 2 fungi ( 1. 8% ) . The main pathogens causing bloodstream infection were Burkholderia spp. ( 33, 29. 5% ) , S. epidermidis( 31, 27. 7% ) , Klebsiella pneumoniae ( 7, 6. 3% ) , S. aureus ( 7, 6. 3% ) , S. hominis ( 6, 5. 4% ) , Acinetobacter baumannii ( 6,5. 4% ) , Pseudomonas aeruginosa( 5, 4. 5% ) and S. haemolyticus( 5, 4. 5%) , suggesting that Burkholderia spp. was predominant pathogenic G- bacteria, and coagulase-negative staphylococcus was predominant G+ bacteria. The antibiotic resistance tests demonstrated that isolated G- bacillus was highly sensitive to carbopenem, while vancomycin-resistant G+ cocci were not found. Conclusions Within the latest 5 years,the prevalence of G+ bacteria infection is almost equivalent to G- bacteria in blood stream infection.Coagulase-negative staphylococcus is the mainly G+ bacteria and Burkholderia spp. is predominant in G- bacteria. Carbopenemand glycopeptides still remain to be the first choice.
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 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 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.
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.
Objective To investigate the characteristics of the pathogens causing bloodstream infection after general surgery in infant and young children patients, and to provide the references for disease treatment and nosocomial infection control. Methods The clinical and laboratory examination data after general surgery in infant and young children patients, who were admitted to our hospital from January 2012 to March 2017, were retrospectively collected. The pathogens and drug resistance were analyzed by SPSS 18.0 software. Results In this study, 109 cases were included, and 117 strains of the pathogens were isolated, including 53 isolates (45.3%) of gram negative bacteria, 41 isolates (35.0%) of gram positive bacteria, and 23 isolates (19.7%) of fungi. Escherichia coli (16/117, 13.7%), Enterococcus faecium (13/117, 11.1%), Candida parapsilosis (12/117, 10.3%), Klebsiella pneumoniae (9/117, 7.7%) and Enterococcus faecalis (8/117, 6.8%) were the top 5 species. Strains producing extended-spectrum beta-lactamase accounted for 87.5% of E. coli (14/16) and 44.4% (4/9) of K. pneumoniae isolates. Both E. faecium and E. faecalis were susceptible to vancomycin. C. parapsilosis showed the susceptibility to the antifungal agents. Conclusion Gram negative bacteria are predominant pathogens causing bloodstream infection after general surgery in infant and young children patients, and infection caused by resistant isolates should be prevented and controlled.
Objective To investigate the risk factors of central line-associated bloodstream infection (CLABSI) and provide clinical guidance for reducing the incidence of CLABSI. Methods The clinical data of patients with central venous catheter catheterization in Sichuan Provincial People’s Hospital between January 2018 and December 2021 were retrospectively collected. According to whether CLABSI occurred, the patients were divided into CLABSI group and non-CLABSI group. The data of patients were analyzed and the risk factors of CLABIS were discussed. Results A total of 43 987 patients were included. Among them, there were 63 cases in the CLABSI group and 43924 cases in the non-CLABSI group. The incidence of CLABSI was 0.18/1 000 catheter days. Multivariate logistic regression analysis showed that admission to intensive care unit (ICU) [odds ratio (OR)=74.054, 95% confidence interval (CI) (22.661, 242.005), P<0.001], hemodialysis [OR=4.531, 95%CI (1.899, 10.809), P=0.001] and indwelling catheter days [OR=1.017, 95%CI (1.005, 1.029), P=0.005] were independent risk factors for CLABSI. A total of 63 strains of pathogenic bacteria were isolated from the 63 patients with CLABSI. Among them, 28 strains of Gram-positive bacteria, 25 strains of Gram-negative bacteria and 10 strains of Candida. Conclusions Admission to ICU, hemodialysis and long-term indwelling catheter are independent risk factors for CLABSI. The prevention and control measures of CLABSI should be strictly implemented for such patients to reduce the risk of infection.
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.