Abstract:The definition and diagnostic criteria of sepsis are constantly updated in recent years, which is an inevitable requirement for optimizing clinical diagnosis and treatment of sepsis, but it brings new challenges to clinical practice at the same time. This paper retrospectively reviews the changes in diagnostic criteria in sepsis 1.0, 2.0 and 3.0 version, and finds that relevant definitions in sepsis guidelines published at home and abroad are insufficient in varying degrees. Over the past three decades, definitions have been changing constantly, different versions of definitions may be adopted in different literatures, which is easy to cause confusion in sepsis knowledge and data, and may result in delayed treatment or blindly expand treatment of clinical sepsis. Diagnostic criteria and epidemiological data of sepsis still need to be further explored and improved, China also needs to consider formulating a series of recommendations that are easy to be measured and conducive to defining patient diagnosis and management.

Abstract:Objective To evaluate the role of PA1864 gene in the virulence and pathogenicity of Pseudomonas aeruginosa (PA). Methods Difference in virulence phenotype and pathogenicity between wild type (PAO1) and PA1864 gene knockout strain (△PA1864) which acutely infected mice lung or A549 lung cancer cells was compared, including the survival rate of mice, pulmonary edema, tissue damage, cell viability, secretory virulence factors of PAO1 and △PA1864 strains, type Ⅲ secretion system (T3SS) of toxic protein and quorum sensing(QS) system and so on. Results When PA1864 gene was knocked out, pathogenicity and cytotoxicity of bacteria to host decreased, bacterial swimming motility and expression of T3SS-related proteins (ExoS, PcrV) were down-regulated, while synthesis of pyocyanin increased, synthesis of signal molecules in quinolone QS system increased. Conclusion PA1864 gene can promote PA virulence, and this regulation may be related to quinolone QS system.

Abstract:Objective To construct replication-defective recombinant adenovirus type 5 (rAd5) vector containing Zika virus (ZIKV) envelope protein prM-E, and determine the expression of prM-E in cells and its immunogenicity in mice. Methods prM-E gene fragment was obtained from ZIKV strain Z16006 (Asian type),recombinant adenovirus rAd5/prM-E was enveloped with recombinant adenovirus AdMax^TM system. C57BL/6 mice were immunized by intramuscular injection of rAd5/prM-E at three doses(10⁷, 10⁸ and 10⁹ PFU), mice were immunized again at the same dose at week 3, blood was taken from the eyeballs of mice and spleen lymphocytes were separated at week 5. Humoral and cellular immune response of mice to ZIKV prM-E were detected by ELISpot and ELISA respectively. Results The replication-defective recombinant adenovirus vector rAd5/prM-E was constructed successfully, expression products of 293A cells infected with rAd5/prM-E were detected by Western blot and anti-ZIKV E antibody, 56 kDa protein band which corresponded with E protein was observed. Spots forming cells (SFCs) secreted by mice splenic lymphocyte specific IFN-γ was detected by ELISpot method, results were (688.54±186.43), (1 084.90±144.14), and (1 640.20±147.13) SFCs/10⁶ splenic cell respectively, which were positively proportional to the immune dose; anti-E antibody in serum of immunized mice was determined by enzyme-linked immunosorbent assay (ELISA), and the titers (log10 value) were (3.14±0.39), (3.50±0.30), and (3.74±0.25) respectively, all were significantly higher than(0.80±0.17) of control group (P<0.001). Conclusion rAd5/prM-E has the ability to infect mice and induce strong specific antibodies and cellular immune response, which indicates that prM-E has good immunogenicity and provides a reliable immune source for the development of ZIKV candidate vaccine.

Abstract:Objective To understand the carrying status of carbapenemase gene and homology of carbapenem-resistant Klebsiella pneumoniae (CRKP) in a hospital, so as to provide laboratory basis for preventing and controlling transmission of CRKP clone strain. Methods 22 strains of CRKP (K1-K22) isolated from clinical departments in a hospital from January to December 2017 were collected, antimicrobial susceptibility testing results were re-checked by Kirby-Bauer disk diffusion and broth microdilution method, carbapenemase production was detected by modified Hodge test and Carba NP test, common carbapenemase genes of enzyme-producing strains were amplified and sequenced by polymerase chain reaction(PCR), homology analysis was performed by multilocus sequence typing (MLST) and enterobacterial repetitive intergenic consensus PCR(ERIC-PCR). Results Resistance rates of 22 CRKP to ertapenem, imipenem and meropenem were all 100%, resistance to other common clinical antimicrobial agents were also high; 13 strains of CRKP were positive for modified Hodge test and 14 were positive for Carba NP test. KPC-2 gene was carried by 14 enzyme-producing strains, NDM-1 gene was also carried by K12 strain. According to MLST method, CRKP strains were divided into ST11 (n=14), ST875 (n=6), ST1964(n=1), and ST571(n=1). According to ERIC-PCR method, CRKP strains were divided into type A (n=15), type B (n=6) and type C (n=1). K1-K6 strains with the same typing results were from intensive care unit (ICU), K7-K10 were from cerebrovascular surgery, and K15-K21 were from neonatology, corresponding patients had the same hospital stay, and they had been transferred (patients K2 and K8 were transferred from cerebrovascular surgery to ICU, K13 and K14 from ICU to departments of hematology and nephrology respectively). Conclusion Cloning epidemics of ST11 and ST875 CRKP existed in this hospital in 2017, it is necessary to strengthen the prevention and control measures of healthcare-associated infection.

Abstract:Objective To analyze antimicrobial susceptibility and carrying status of drug resistance genes of carbapenem-resistant Klebsiella pneumoniae (CRKP) in a hospital. Methods CRKP isolated from a hospital between January 2017 and June 2018 were collected, antimicrobial susceptibility of strains was analyzed, polymerase chain reaction (PCR) was used to detect carrying status of drug resistance genes. Results A total of 57 strains of CRKP were collected, mainly from respiratory tract specimens, including sputum (n=34) and alveolar lavage fluid (n=11). The main source departments of CRKP were department of neurology (n=20, 35.09%), department of respiratory medicine (n=15, 26.32%), and department of critical medicine (n=9, 15.79%). CRKP was resistant to most antimicrobial agents, but resistance rates to some antimicrobial agents were relatively low, compound sulfamethoxazole had the lowest resistance rate (15.79%), followed by tegacycline (50.88%) and amikacin (57.89%). Two carbapenemase genes (KPC-2, NDM-1) and four extended-spectrum β-lactamases (ESBLs) genes (SHV, CTX-M-9, TEM, CTX-M-1) were detected. 57 strains of CRKP were all detected ESBLs genes, 39 (68.42%) of which were detected KPC-2 gene, and only 1 was detected NDM-1 gene. Conclusion Antimicrobial resistance of clinically isolated CRKP is severe, CRKP carries multiple drug resistance genes, the most common carbapenemase is KPC.

Abstract:Objective To study the molecular epidemiological characteristics of drug resistance of carbapenem-resistant Enterobacteriaceae (CRE) in a hospital, and provide evidence for the prevention and control of CRE. Methods CRE stored in the bacterial laboratory of a hospital from 2013 to 2017 were collected and performed multilocus sequence typing (MLST), antimicrobial susceptibility testing as well as whole-genome sequencing, carbapenem resistance genes carried in some CRE strains were conducted gene environment analysis. Results A total of 62 strains of CRE were collected and 51 were successfully revived, including 30 strains of carbapenem-resistant Klebsiella pneumoniae(CRKP), 9 strains of carbapenem-resistant Escherichia coli (CREC),6 strains of carbapenem-resistant Enterobacter cloacae (CRECL), and 6 strains of other CRE. CRKP MLST mainly included 3 ST147 strains and 2 ST11 strains; CREC MLST mainly included 3 ST167 strains; CRECL MLST mainly included 3 ST93 strains and 2 ST88 strains. 51 strains of CRE showed the highest resistance to ampicillin and cefotaxime, all were 100%. Distribution of carbapenem resistance genes was follows:1, 14, 18, 22, 2,10, 10, 2, and 2 strains carried bla_KPC-2, bla_IMP-4, bla_NDM-1, bla_NDM-5, bla_NDM-9, bla_OXA-1, bla_OXA-10, bla_OXA-23, and bla_OXA-66 respectively. Genetic environment of bla_NDM-1, bla_NDM-5, bla_NDM-9, and bla_IMP-4 in different strains was analyzed, it was found that the genetic environment of several drug-resistant genes was similar to the previously reported genetic environment, there was no significant difference among strains. Conclusion Drug resistance genes can be stable in different CRE strains through horizontal transmission, which poses a threat to the prevention and control of healthcare-associated infection.

Abstract:Objective To investigate the epidemic status and transmission mechanism of bla_NDM-1 gene-carrying Escherichia coli(E. coli) in a hospital. Methods 92 strains of carbapenem-non-susceptible E. coli were collected from a hospital affiliated to Nanchang University between January and December 2016, bla_NDM-1 gene was screened and other common carbapenemase genes in bla_NDM-1 positive E. coli were also detected. bla_NDM-1 positive E. coli (donor) and E. coli J53 (receptor) was performed conjugation testing, phenotyping of conjugants was validated by antimicrobial susceptibility testing and modified carbapenem inactivation method(mCIM), plasmids of donor strain and conjugator were extracted, bla_NDM-1 gene was located by Southern blot, and horizontally transfer ability of bla_NDM-1 gene was validated. Results Among 92 strains of carbapenem-non-susceptible E. coli, 2 strains were found to carry bla_NDM-1 gene, carrying rate was 2.2%. Other common carbapenemase genes were also found in these two strains of E. coli. Conjugation testing and Southern blot found that bla_NDM-1 gene of these two E. coli strains was located on the plasmid of E. coli strain, and bla_NDM-1 gene of one E. coli strain could be transferred to E. coli J53 through plasmid. Antimicrobial susceptibility testing showed that these two E. coli strains were both resistant to multiple clinically used antimicrobial agents, conjugants obtained similar susceptibility results to the donor bacteria. mCIM showed that these two E. coli strains and their conjugants all produced NDM-1 carbapenemase. Conclusion E. coli carrying bla_NDM-1 gene and producing NDM-1 carbapenemase is found in this hospital, E. coli carrying bla_NDM-1 gene is resistant to most clinically used antimicrobial agents, plasmids can mediate the horizontal transfer of bla_NDM-1 gene.

Abstract:Objective To explore the diagnostic value of Clostridium difficile (C. difficile) glutamate dehydrogenase (GDH) antigen and toxin detection kit (C. Diff Quik Chek Complete^®) in C. difficile infection (CDI). Methods Literatures were screened according to inclusion and exclusion criteria, literatures about CDI diagnosed by C. Diff Quik Chek Complete^® were retrieved, quality assessment tool QUADAS for diagnostic accuracy research was used to perform quality evaluation, Meta-DiSc 1.4 software was used to conduct Meta-analysis. Results A total of 8 literatures and 2 852 research subjects were included in the study. The included literatures are of high quality, heterogeneity test showed that there was no threshold effect, but there was non-threshold heterogeneity due to other causes. Meta-analysis was performed with random effect model, results showed that the combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic dominance ratio (95% CI) of diagnosis of CDI through C. Diff Quik Chek Complete^® GDH antigen detection were 0.96 (0.94, 0.98), 0.96 (0.95, 0.97), 20.07 (13.47, 29.92), 0.04 (0.03, 0.07), and 409.35 (168.01, 997.39) respectively; toxin detection for diagnosis of CDI were 0.54 (0.48, 0.59), 1.00 (0.99, 1.00), 64.23 (18.90, 218.33), 0.48 (0.37, 0.62), and 142.74 (40.94, 497.61) respectively. The area under the summary receiver operating characteristic curve (AUC^SROC) of GDH antigen and toxin detection for diagnosis of CDI were 0.9877 and 0.9529 respectively, and Q^* index were 0.9718 and 0.9228 respectively. Conclusion The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic dominance ratio of antigen detection by C. Diff Quik Chek Complete^® are high, although the sensitivity of toxin detection is not perfect, its specificity is high, which can be used as the primary screening kit for CDI in areas and hospitals lacking professional equipment and conditions.

Abstract:Objective To evaluate the effect of various antimicrobial agents on preventing intracranial infection after craniocerebral surgery, and provide reference for antimicrobial prophylaxis in patients undergoing craniotomy. Methods Randomized controlled trials on prevention of intracranial infection after craniocerebral surgery were retrieved from domestic and foreign databases, after conducting literature screening, data extracting, and literature quality evaluation according to inclusion and exclusion criteria, Bayesian network Meta-analysis was performed with calling JAGS by GeMTC. Results A total of 3 214 patients after craniocerebral surgery in 11 studies were included in analysis, 159 patients had postoperative intracranial infection, including 33 patients in antimicrobial use group and 126 in control group, quality of literatures was good, consistency test showed that there was no obvious inconsistency between the direct and indirect comparison. Bayesian network Meta-analysis showed that antimicrobial prophylaxis could reduce the incidence of intracranial infection after craniocerebral surgery, but there was no significant difference between cephalosporin, clindamycin, fusidic acid, vancomycin, and penicillin. Conclusion Current evidence shows that preoperative intravenous injection of different antimicrobial agents had no significant difference in preventing intracranial infection after craniocerebral surgery, therefore, low-level antimicrobial agents can be selec-ted to prevent intracranial infection after craniocerebral surgery, more high-quality and large-sample studies are still needed to confirm this.

Abstract:Objective To investigate the carrying status of methicillin-resistant Staphylococcus aureus (MRSA) resistance genes and virulence factor pvl gene in sputum of patients with healthcare-associated pneumonia(HAP). Methods Forty-six strains of MRSA from sputum of patients with HAP in an intensive care unit (ICU) of a hospital were detected resistance genes (mecA, aacA-D, tetK, tetM, msrA, msrB, ermA, ermC, vatA, vatB, vatC, femB and linA) and virulence factor pvl gene by polymerase chain reaction (PCR), SCCmec genotypes of MRSA strains were analyzed by PCR. Results Among 46 MRSA strains, detection rates of resistance genes mecA, aacA-D, tetK, msrA, ermA, ermC, femB, and linA were 100%, 54.35%, 36.96%, 13.04%, 36.96%, 52.17%, 71.74%, and 10.87% respectively. None of strains were detected tetM, msrB, vatA, vatB, and vatC genes; virulence factor pvl gene carrying rate was 65.22%. Four genotypes of SCCmec were detected among 46 MRSA strains, 26.09%, 52.17%, 2.17%, and 2.17% of which were SCCmec Ⅱ, Ⅲ, IVc, and V respectively. Conclusion MRSA carries multiple drug resistance genes in sputum of patients with HAP, virulence gene pvl is high, SCCmec genotype is mainly type Ⅲ, health care workers should pay highly attention.

Abstract:Objective To understand the current situation of healthcare-associated infection(HAI) in Inner Mongolia, and provide basis for formulating management measures for HAI. Methods According to the requirement of national HAI surveillance network in 2018, all tertiary and secondary general hospitals and specialty hospitals in Inner Mongolia voluntarily participated in cross-sectional survey on prevalence rate of HAI, independently selected survey date and filled in unified questionnaire. Results In 2018, a total of 169 hospitals in Inner Mongolia participated in prevalence rate survey, 61 469 patients were investigated. 1 016 patients had 1 100 cases of HAI, prevalence rate and case prevalence rate of HAI were 1.65% and 1.79% respectively. Prevalence rates of HAI in hospitals ≥ 900 beds was 2.60%. The top three departments with higher prevalent rates of HAI were general intensive care unit (ICU) (12.70%), department of hematology (6.55%), and neonatal group of department of pediatrics (5.98%). The main HAI sites were lower respiratory tract (44.82%), urinary tract (16.82%), and upper respiratory tract (10.82%). Antimicrobial usage rate was 28.04%, there was a significant difference in antimicrobial usage rate among hospitals of different sizes (χ²=650.353,P<0.001). Pathogenic detection rate of patients with therapeutic antimicrobial use was 36.08%. The larger scale of hospitals, the higher rate of pathogenic detection in patients with therapeutic antimicrobial use, difference was statistically significant(χ²=449.309,P<0.001). The top three departments with higher therapeutic antimicrobial use were non-neonatal group of department of pediatrics (n=1 821, 98.11%), department of respiratory medicine (n=2 463, 97.62%) and department of nephrology (n=334, 96.53%); department with more antimicrobial use were departments of obstetrics (n=484, 82.59%), departments of gynecology (n=395, 66.72%) and departments of orthopaedics (n=1 106, 64.68%). A total of 457 pathogens causing HAI were detected, including 325 strains (71.12%) of gram-negative bacteria, 82 (17.94%) gram-positive bacteria and 30 (6.57%) fungi. The main pathogens causing HAI were Klebsiella pneumoniae (n=82), Escherichia coli (n=81), and Pseudomonas aeruginosa (n=76). Conclusion The prevalence rate of this survey is lower than the whole country and other regions. HAI management departments can take effective measures to prevent and control infection in key departments and main infection sites, and improve pathogenic detection rate of therapeutic antimicrobial use in small hospitals.

Abstract:Objective To investigate the distribution and antimicrobial resistance of clinically isolated bacteria in a hospitals from 2013 to 2018, and provide reference for rational use of antimicrobial agents in clinic. Methods Bacterial strains isolated from specimens of hospitalized patients in different clinical departments in a hospital from 2013 to 2018 were analyzed retrospectively, including the name of strains, specimen sources and antimicrobial susceptibi-lity, data were analyzed by WHONET 5.6 and SPSS 20.0 software. Results A total of 5 014 strains of bacteria were isolated in 2013-2018, 3 797 (75.73%) of which were gram-negative bacteria. The main isolated bacteria were Escherichia coli (n=1 182, 23.57%), Klebsiella pneumoniae (n=669, 13.34%), and Pseudomonas aeruginosa (n=408, 8.14%). Escherichia coli and Klebsiella pneumoniae were sensitive to carbapenems, antimicrobial resistance rates were all<10%. Resistance rates of Pseudomonas aeruginosa to imipenem and meropenem were 29.31% and 20.88% respectively. Resistance rates of Acinetobacter baumannii to imipenem and meropenem were 61.71% and 53.74% respectively. Resistance rate of Staphylococcus aureus to oxacillin was 42.14%, vancomycin and line-zolid-resistant strains was not found. Conclusion Antimicrobial resistance of clinically isolated common bacteria in this hospital is relatively stable in recent years, with an overall downward.

Abstract:Objective To investigate the change in clinical distribution and antimicrobial resistance of Klebsiella pneumoniae(KP), and provide evidence for KP infection control and treatment. Methods 10 075 strains of KP isolated from a hospital from 2009 to 2018 were analyzed retrospectively, constituent of KP in different years, different departments and different infection sites were compared, changing trend of resistance of KP was analyzed. Results KP mainly isolated from sputum specimens, which was the main pathogen of liver abscess and the most isolated pathogen from department of neonatology. Isolation rate of KP increased from 8.0% in 2009 to 13.8% in 2018, showing an upward trend year by year (χ_trend²=389.9, P<0.001). Resistance rates of KP to imipenem and meropenem increased from 0.6% and 1.5% to 34.4% and 32.8% respectively during 10 years; isolation rates of ESBLs-producing KP increased from 18.8% to 62.6%. KP isolated from general intensive care unit(ICU) and department of neurology showed the highest resistance rate to imipenem, rising from 1.9% and 0 to 63.7% and 52.9% respectively, antimicrobial resistance rates of KP from blood, sputum, urine, and abdominal drainage increased to from 0, 1%, 0, and 0 to 29.3%, 26.6%, 34.0%, and 22.9% respectively. Conclusion The isolation rate and antimicrobial resistance rate of KP showed a continuous upward trend during 10 years, isolation rate of CRKP also showed a continuous upward trend, there were differences among different departments and different infection sites.

Abstract:Objective To investigate the causes of a suspected outbreak of healthcare -associated infection(HAI) in deep surgical incision caused by Aeromonas hydrophila(A. hydrophila) after aortic dissection operation (Standfond A), and provide evidence for effective control of infection. Methods A. hydrophila infection occurred in 3 patients after cardiac surgery in an cardiothoracic surgery intensive care unit (ICU) from September to October 2018 were investigated, deep incision drainage pus and venous blood of patients was collected, identification and antimicrobial susceptibility testing of strains were performed, epidemiological investigation and analysis was carried out. Results A. hydrophila was isolated from deep incision drainage pus and blood of 3 patients after aortic dissection operation, all were sensitive to amikacin, but resistant to other antimicrobial agents. External duct of ventilator of patient No. 2 and surface of bed unit of patient No. 3 were also isolated A. hydrophila, antimicrobial susceptibility testing results were consistent with A. hydrophila isolated from countertop of sink in ward of patient No. 1. After taking measures, such as isolation treatment for patients, strengthening hand hygiene of health care workers(HCWs), and strict implementing contact isolation, no new case of HAI caused by A. hydrophila occurred. Conclusion This event is a suspected outbreak of HAI, environmental contamination in the vicinity of patients is a possible source of transmission.

Abstract:Objective To investigate the homology of Acinetobacter baumannii (A. baumannii) isolated from patients and environment in intensive care unit(ICU) of a hospital. Methods 180 sepcimens from patients and environment in ICU of a hospital in Jiangsu Province were performed A. baumannii isolation, antimicrobial susceptibility analysis and pulsed-field gel electrophoresis (PFGE) typing. Results 180 specimens were isolated 41 strains of A. baumannii, including 9 clinical strains and 32 environmental strains. Antimicrobial susceptibility testing result showed that resistance rates of A. baumannii to other antimicrobial agents were all higher than 70%, except for levofloxacin (34.1%). 41 strains of A. baumannii were classified into 19 PFGE genotypes, there were at least 2 strains in each of the five types(type I, M, N, O, and P), the others were all one type; there were 16 strains of type P, 5 of which were from patients with HAI, and the rest were from patients' ventilators, treatment vehicles and the surrounding, the detection time span of this type of A. baumannii was 141days. Conclusion A. baumannii isolated from patients and environment in ICU of this hospital has homology, and there is transmission in hospital and epidemic of HAI. Supervision of disinfection measures should be strengthened in order to avoid the occurrence and epidemic of HAI as far as possible.

Abstract:Objective To explore the predictive effect of Glasgow Coma Scale (GCS) score on healthcare-associa-ted infection(HAI) in stroke patients undergoing surgery, and provide scientific basis for health care worker to take effective preventive measures. Methods Stroke patients who underwent surgery in the neurosurgery ward of a tertiary first-class teaching hospital from January 1, 2016 to December 31, 2018 were conducted prospective targeted surveillance, a self-designed questionnaire was used to collect patients' demographic and clinical data, clinical diffe-rences among patients were compared; accuracy of GCS in predicting HAI was tested by receiver operating characte-ristic curve (ROC curve). Results A total of 816 stroke patients were enrolled in study, 213 (26.10%) of whom had HAI, with the decrease of GCS score, HAI rate of patients showed an upward trend; pulmonary infection and surgical site infection were the most common in patients with GCS score>9, and pulmonary infection and multi-site infection were most common in patients with GCS score of 3-8. ROC curve analysis showed that area under curve of GCS score of stroke HAI, pulmonary infection, urinary tract infection, surgical site infection, and blood stream infection were 0.747 (95% CI:0.707-0.786), 0.799 (95% CI:0.759-0.838), 0.789 (95% CI:0.722-0.856), 0.565 (95% CI:0.492-0.638), and 0.730 (95% CI:0.509-0.952) respectively, with significant differences (all P<0.05). Conclusion GCS score of stroke patients has a significant predictive effect on HAI, for high-risk patients with low GCS score, effective infection prevention measures should be taken to reduce the incidence of infection.

Abstract:Objective To detect status and scope of faucet contamination in intensive care unit(ICU), so as to provide basis for rational layout around the faucets and reducing water-borne infection. Methods Cotton-swab sampling method was used to take specimens from two faucet outlets and their surroundings in ICU of a tertiary general hospital, taking the outlet as the center, each specimen was taken every 20-30 cm, specimens were detected by ATP technique, conventional microbial detection and next-generation sequencing technique(NGS), contamination status and splash range around faucets and their surroundings were analyzed. Results In the case of conventional cleaning, faucets and their surrounding area within 70 cm was highly contaminated. The qualified rates of ATP detection and conventional microbial detection were 60.0% and 73.3% respectively. ATP detection results of two faucet outlets were 2 526 RLU/piece and 687 RLU/piece respectively, microbial detection showed that the number of colonies were both>10⁵ CFU/cm². In the area 70 cm away from the outlets, the number of bacterial colonies still exceeded the standard. The NGS detection showed that Moraxella osloensis with high coverage was found from the faucet outlets to their surroundings, which was consistent with the distribution of bacteria at the outlets. Conclusion Faucet is an important source of contamination in the ward, cleaning of faucet and its surroundings should be paid attention, clean articles and articles related to patients should not be placed within 1 meter.

Abstract:Objective To compare and analyze the efficacy and cost of endoscope cleaning and disinfection detected with membrane filtration method and smear method. Methods Endoscopes after cleaning and disinfection in a large tertiary first-class general hospital from January to December 2018 were randomly selected, cleaning and disinfection efficacy of endoscopes were detected with membrane filtration method and smear method respectively, the qualified rate, pathogen detection rate, bacterial colony count and cost between two methods were compared, QuestionStar^TM and WeChat platform were used to investigate the current status of detection methods for endoscope cleaning and disinfection efficacy in some hospitals. Results A total of 207 flexible endoscopes were detected. The qualified rates of endoscopes detected with membrane filtration method and smear method were 78.26% and 95.65% respectively, difference was statistically significant (P<0.001). After endoscopes were cleaned and disinfected, pathogen detection rate and bacterial colony count detected with membrane filtration method were both higher than smear method, difference was statistically significant (P<0.001). Compared with smear method, economic cost of 207 endoscopes detected with membrane filtration method increased by 1 498.48 yuan per year, with an average increase of 7.24 yuan per endoscope. On average, each endoscope detected with membrane filtration method took 62 seconds longer than smear method. A total of 26 hospitals were investigated endoscope cleaning and disinfection detection methods, only 2 hospitals adopted membrane filtration method. For membrane filtration method to detect the cleaning and disinfection efficacy of endoscopes, the most important issue concerned by hospitals was increased economic cost. Conclusion Membrane filtration method can effectively cultivate bacteria in the eluent of endoscopes and objectively reflect the cleaning and disinfection efficacy of endoscopes.

Abstract:Objective To analyze risk factors for healthcare-associated Candida infection(Candida HAI) in pedia-tric inpatients. Methods Patients with fungal HAI in a hospital from January to December 2018 were selected as infection group, according to 1:1 matching method, patients without fungal infection in the same ward at same admission period and of same age group were randomly selected as control group, Candida HAI and risk factors in infected patients were analyzed. Results From January to December 2018, there were 50 patients with fungal HAI in department of pediatrics, and 50 cases were successfully matched in control group. Among 50 cases of fungal HAI, 23 cases were in department of pediatric general surgery. A total of 68 strains of fungi were isolated, mainly Candida parapsilosis (n=28, 41.18%), followed by Candida tropicalis (n=12, 17.65%), and Candida albicans (n=11, 16.18%). Department of pediatric general surgery ranked first in the number of isolated fungi(n=27), the main type of fungal HAI was bloodstream infection (n=38, 76.00%). Univariate analysis showed that the incidence of HAI was higher in patients with length of hospital stay ≥ 21 days, gastrointestinal surgery, duration of antimicrobial use>2 weeks, tracheal intubation, bacteremia, and intravenous hyperalimentation; multivariate analysis showed that antimicrobial use>2 weeks and tracheal intubation were independent risk factors for fungal HAI in pediatric inpatients. Resistance rates of Candida parapsilosis, Candida tropicalis, Candida albicans, and Candida lusitaniae to amphotericin B and fluorcytosine were all high (82.14%-100.00%). Conclusion The main pathogen of fungal HAI in pediatric inpatients is Candida parapsilosis, which mainly occurs in department of pedia-tric surgery, antimicrobial use>2 weeks and tracheal intubation can increase the risk of fungal HAI in pediatric inpatients, effective nursing measures can improve the prognosis of patients.

Abstract:Objective To explore risk factors for postoperative infection in patients with gastric cancer, and provide evidence for prevention and control of infection. Methods A retrospective survey was conducted among patients with gastric cancer who underwent radical gastrectomy in Gansu Provincial Hospital from 2012 to 2018, survey was conducted with a self-designed questionnaire, patients' medical records were reviewed, basic characteristics of patients, operation-related conditions, infection status and so on were surveyed. Patients were divided into infection group and non-infection group according to whether they had postoperative infection or not, clinical parameters were compared and risk factors for postoperative infection were analyzed. Results A total of 427 patients underwent radical gastrectomy, 60 in infection group and 367 in non-infection group. Postoperative infection rate was 14.05%, respiratory tract infection was the main infection, accounting for 41.67%. 60 patients were isolated 63 strains of pathogenic bacteria, mainly gram-positive bacteria (n=34, 53.97%). Gram-positive bacteria were mainly Streptococcus viridans (n=19), and 5 strains of methicillin-resistant Staphylococcus aureus (MRSA) were also isolated. Among 60 patients with postoperative infection, 44(73.33%) were infected with single pathogen, 9 (15.00%) with two pathogens and 7 (11.67%) with three pathogens. Univariate analysis showed that smoking, peptic ulcer, resection site, preoperative hospital stay, duration of operation, postoperative bed rest time, duration of venous cathe-terization and total hospital stay were influencing factors for postoperative infection in patients with gastric cancer (all P<0.05). Logistic regression analysis showed that history of underlying diseases of peptic ulcer (OR, 2.577[95%CI, 1.193-5.568]) and long duration of hospital stay before operation (OR, 2.227[95%CI, 1.079-4.599]) were independent risk factors for postoperative infection in patients with gastric cancer. Conclusion Incidence of post-operative infection in patients with gastric cancer in this hospital is high, health care workers can take effective preventive and control measures against the related risk factors, especially control of underlying diseases of peptic ulcer before operation and pre-operative hospital stay.

Abstract:Objective To investigate the incidence and risk factors of peripherally inserted central catheter(PICC)-related bloodstream infection in neonates. Methods The occurrence of catheter-related bloodstream infection(CRBSI) in neonates receiving PICC in a neonatal ward from January 2016 to December 2017 was analyzed retrospectively, risk factors for CRBSI were analyzed by univariate and multivariate analysis respectively. Results A total of 424 neonates with PICC had CRBSI, the total PICC days were 9 207 days, 53 children had CRBSI, incidence of CRBSI was 5.76/1 000 catheter-days. 57 strains of pathogenic bacteria were isolated, mainly gram-positive bacteria (n=20 strains, 35.09%). Risk factor analysis showed that birth weight ≤ 1 500 g, catheterization days ≥ 20 days, 5-min Apgar score ≤ 7 were independent risk factors for CRBSI in neonates receiving PICC. Conclusion Health care wor-kers can take targeted measures to reduce the incidence of CRBSI in neonates, especially those with birth weight <1 500 g, 5-min Apgar score ≤ 7, and indwelling days ≥ 20 days.

Abstract:Objective To estimate the incidence of healthcare-associated infection(HAI) based on the survey results of prevalence rate of HAI in a hospital, and provide scientific basis for key interventions to reduce the incidence of HAI. Methods The survey data of HAI prevalence rate in a tertiary first-class hospital in 2018 were retrospectively analyzed, Rhame and Suddertth formula was used to estimate the incidence of HAI in different departments and at different sites. Results Prevalence rate and estimated incidence of HAI were 3.84% and 4.57% respectively. Prevalence rate of HAI in intensive care unit was the highest (16.13%), the estimated incidence in department of pediatrics was the highest (8.78%). Prevalence rate and incidence of HAI in lower respiratory tract was the highest (2.35% and 2.28% respectively). Conclusion It is suggested that survey on prevalence and estimated incidence of HAI should be reported at the same time, so as to improve the scientific nature of intervention measures and reduce the occurrence of HAI.

Abstract:Central line-associated bloodstream infection (CLABSI) is one of the common complications of continuous renal replacement therapy(CRRT), it not only increases the usage rate of antimicrobial agents, prolongs patient's length of hospital stay, but also increases the cost of hospitalization. This paper summarized the relevant literatures in recent years on occurrence status, risk factors, as well as prevention and control measures of CLABSI in CRRT patients, aims to arouse great attention of clinical health care workers, and provide basis and reference for the prevention and control of CLABSI in CRRT patients.

Abstract:Clostridium difficile (C. difficile) is a gram-positive anaerobic bacillus and has become a major intestinal pathogen worldwide. C. difficile infection (CDI) can cause antimicrobial-associated diarrhea, severe infection may lead to severe complications such as pseudomembranous colitis and toxic megacolon. CDI is becoming a continuing challenge to public health worldwide. In this paper, the diagnosis, prevention and treatment of CDI at home and abroad in recent years are briefly reviewed, so as to provide a basis for the prevention and treatment of CDI.