Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical bacterial isolates from bloodstream infections in China in 2021.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2021 to December 2021. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 11 013 bacterial strains were collected from 51 hospitals, of which 2 782 (25.3%) were Gram-positive bacteria and 8 231 (74.7%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.6%), Klebsiella pneumoniae (18.9%), Staphylococcus aureus (9.8%), coagulase-negative Staphylococci (6.3%), Pseudomonas aeruginosa (3.6%), Enterococcus faecium (3.6%), Acinetobacter baumannii (2.8%), Enterococcus faecalis (2.7%), Enterobacter cloacae (2.5%) and Klebsiella spp (2.1%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 25.3% and 76.8%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci was detected; more than 95.0% of Staphylococcus aureus were sensitive to ceftobiprole. No vancomycin-resistant Enterococci strains were detected. The rates of extended spectrum B-lactamase (ESBL)-producing isolated in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 49.6%, 25.5% and 39.0%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.2% and 15.8%, respectively; 7.9% of carbapenem-resistant Klebsiella pneumoniae was resistant to ceftazidime/avibactam combination. Ceftobiprole demonstrated excellent activity against non-ESBL-producing Escherichia coli and Klebsiella pneumoniae. Aztreonam/avibactam was highly active against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii (5.5% and 4.5%). The prevalence of carbapenem-resistance in Pseudomonas aeruginosa was 18.9%. Conclusions:The BRICS surveillance results in 2021 shows that the main pathogens of blood stream infection in China are gram-negative bacteria, in which Escherichia coli is the most common. The MRSA incidence shows a further decreasing trend in China and the overall prevalence of vancomycin-resistant Enterococci is low. The prevalence of Carbapenem-resistant Klebsiella pneumoniae is still on a high level, but the trend is downwards.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2018 to December 2019. Antibiotic susceptibility tests were conducted with agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 14 778 bacterial strains were collected from 50 hospitals, of which 4 117 (27.9%) were Gram-positive bacteria and 10 661(72.1%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.2%), Klebsiella pneumoniae (17.0%), Staphylococcus aureus (9.7%), coagulase-negative Staphylococci (8.7%), Pseudomonas aeruginosa (3.7%), Enterococcus faecium (3.4%), Acinetobacter baumannii(3.4%), Enterobacter cloacae (2.9%), Streptococci(2.8%) and Enterococcus faecalis (2.3%). The the prevalence of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus were 27.4% (394/1 438) and 70.4% (905/1 285), respectively. No glycopeptide-resistant Staphylococcus was detected. More than 95% of S. aureus were sensitive to amikacin, rifampicin and SMZco. The resistance rate of E. faecium to vancomycin was 0.4% (2/504), and no vancomycin-resistant E. faecalis was detected. The ESBLs-producing rates in no carbapenem-resistance E. coli, carbapenem sensitive K. pneumoniae and Proteus were 50.4% (2 731/5 415), 24.6% (493/2001) and 35.2% (31/88), respectively. The prevalence of carbapenem-resistance in E. coli and K. pneumoniae were 1.5% (85/5 500), 20.6% (518/2 519), respectively. 8.3% (27/325) of carbapenem-resistance K. pneumoniae was resistant to ceftazidime/avibactam combination. The resistance rates of A. baumannii to polymyxin and tigecycline were 2.8% (14/501) and 3.4% (17/501) respectively, and that of P. aeruginosa to carbapenem were 18.9% (103/546). Conclusions:The surveillance results from 2018 to 2019 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while E. coli was the most common pathogen, and ESBLs-producing strains were in majority; the MRSA incidence is getting lower in China; carbapenem-resistant E. coli keeps at a low level, while carbapenem-resistant K. pneumoniae is on the rise obviously.

Objective:To investigate the nutritional status of elderly inpatients in China, and to assess its relationship with clinical outcomes.Methods:A prospective, multicenter, parallel investigation was organized and conducted by the Chinese Medical Association's Group of Geriatric Nutrition Support.Patients aged ≥65 years from 30 major hospitals of 14 cities in China were evaluated by the Nutritional Risk Screening 2002(NRS2002)and the Mini-Nutritional Assessment-Short Form(MNA-SF), in order to understand the nutritional status and nutritional risk of elderly inpatients in China.The indicators of clinical outcomes were summarized, and the correlation between nutritional status and clinical outcomes was analyzed.Results:A total of 10 184 elderly patients who met the inclusion criteria were enrolled in this study, aged 65-112(74.81±7.01)years, with a body mass index(BMI)of 17.80-35.50(23.32±3.83)kg/m 2.Grip strength of the dominant hand was(16.95±18.42)kg, upper arm circumference was(25.68±3.70)cm, and calf circumference was(32.07±3.89)cm.BMI, grip strength, upper arm circumference and calf circumference decreased significantly with age( F=13.74, 97.47, 28.31 and 88.68, all P<0.001). NRS2002 was conducted on 10 182 patients.Of them, 10.14%(895/10 182)suffered malnutrition(BMI≤18.5 kg/m 2), and 46.42%(4 726/10 182)were at nutritional risk(NRS2002 score≥3). Nutrition deficiency and nutritional risk showed upward trends with age( F=43.41 and 177.05, both P<0.001). A total of 9 755 patients(95.79%, 9 755/10 182)completed the MNA-SF.Of them, 14.67%(1 431/9 755)had malnutrition, 35.04%(3 418/9 755)were at risk of malnutrition, and 50.29%(4 906/9 755)had normal nutritional status.The incidence of malnutrition and the risk of malnutrition significantly increased with age( F=172.79, 12.10 and 152.42, all P<0.05). Nutritional risk(NRS2002 score≥3)was related to age, BMI, mortality, infectious complications, length of hospital stay and total hospital cost(all P<0.05). Conclusions:The incidence of malnutrition and the risk of malnutrition are high in elderly inpatients in China.Nutritional risk is an influencing factor for adverse clinical outcomes.

Objective:To investigate the bacterial composition and antimicrobial resistance profile of clinical isolates from bloodstream infections in China.Methods:The clinical bacterial strains isolated from blood culture were collected during January 2020 to December 2020 in member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS). Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute(CLSI, USA). WHONET 5.6 was used to analyze data.Results:During the study period, 10 043 bacterial strains were collected from 54 hospitals, of which 2 664 (26.5%) were Gram-positive bacteria and 7 379 (73.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (38.6%), Klebsiella pneumoniae (18.4%), Staphylococcus aureus (9.9%), coagulase-negative Staphylococci (7.5%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.3%), Enterobacter cloacae (2.8%), Enterococcus faecalis (2.6%), Acinetobacter baumannii (2.4%) and Klebsiella spp (1.8%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 27.6% and 74.4%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci were detected. More than 95% of Staphylococcus aureus were sensitive to rifampicin and SMZco. No vancomycin-resistant Enterococci strains were detected. Extended spectrum β-lactamase (ESBL) producing Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 48.4%, 23.6% and 36.1%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.3% and 16.1%, respectively; 9.6% of carbapenem-resistant Klebsiella pneumoniae strains were resistant to ceftazidime/avibactam combination. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii. The prevalence rate of carbapenem-resistance of Pseudomonas aeruginosa was 23.2%. Conclusions:The surveillance results in 2020 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen, and ESBL-producing strains declined while carbapenem-resistant Klebsiella pneumoniae kept on high level. The proportion and the prevalence of carbapenem-resistant Pseudomonas aeruginosa were on the rise slowly. On the other side, the MRSA incidence got lower in China, while the overall prevalence of vancomycin-resistant Enterococci was low.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2016 to December 2017. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI) 2019. WHONET 5.6 was used to analyze data.Results:During the study period, 8 154 bacterial strains were collected from 33 hospitals, of which 2 325 (28.5%) were Gram-positive bacteria and 5 829 (71.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (34.7%), Klebsiella pneumoniae (15.8%), Staphylococcus aureus (11.3%), coagulase-negative Staphylococci (7.4%), Acinetobacter baumannii (4.6%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.8%), Streptococci (2.9%), Enterobacter cloacae (2.7%) and Enterococcus faecalis (2.5%). Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MRCNS) accounted for 34.2%(315/922) and 77.7%(470/605), respectively. No vancomycin-resistant Staphylococcus was detected. The resistance rate of Enterococcus faecium to vancomycin was 0.6%(2/312), and no vancomycin-resistant Enterococcus faecium was detected. The ESBLs-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus were 55.7%(1 576/2 831), 29.9%(386/1 289) and 38.5%(15/39), respectively. The incidences of carbapenem-resistance in Escherichia coli, Klebsiella pneumoniae were 1.2%(33/2 831), 17.5%(226/1 289), respectively. The resistance rates of Acinetobacter baumannii to polymyxin and tigecycline were 14.8%(55/372) and 5.9%(22/372) respectively, and those of Pseudomonas aeruginosa to polymyxin and carbapenem were 1.3%(4/315) and 18.7%(59/315), respectively. Conclusion:The surveillance results from 2016 to 2017 showed that the main pathogens of blood stream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen; the MRSA incidence was lower than other surveillance data in the same period in China; carbapenem-resistant Escherichia coli was at a low level during this surveillance, while carbapenem-resistant Klebsiella pneumoniae is on the rise.

Objective To investigate the feasibility of reducing CT scanning dose in the process of 125I radioactive seed implantation.Methods GEMS phantom and 062 M phantom were scanned using GE Lightspeed RT large hole CT with 120 kV,100 kV and 80 kV separately,and 150-10 mA (20 mA decreased progressively).The scanning dose,CT value and noise of the region of interest were recorded and the image quality was evaluated.Image signal-to-noise ratio (SNR) and contrast to noise ratio (CNR) values were calculated.Results With the decreasing of tube voltage and current,the SNR values were reduced accorgingly.The values had significant difference with those of standard images except the images acquired with 120 kV,150-70 mA and 100 kV,150-90 mA (t =-9.294-3.717,P ＜0.05).With the decreasing of the tube voltage and current,the CNR decreased significantly.The image quality was too low to evaluate while CNR lower than 2.The high contrast resolution of the CT images were not affected obviously with the tube voltage and current lowering.Conclusions In the process of 125I radioactive seed implantation,it is feasible to choose lower tube voltage and tube current(100 kV,70 mA) to scan the same area repeatedly except for the first scan with standard chest scanning parameters.The patient radiation dose has fallen dramatically.

Objective To establish a simple scoring system for the diagnosis of liver fibrosis in chronic hepatitis B (CHB), and to observe its sensitivity and specificity. Methods Two hundred and thirty-three patients diagnosed as CHB by liver biopsy were divided into model group (N = 154) and validation group (N = 79). The general information, biochemical parameters and imaging data of all patients were observed. With hepatic fibrosis being obvious or not as the end point of primary study in the model group, we established a simple scoring system for the diagnosis. The cut-off, sensitivity and specificity of the system were tested in the model group by ROC curve, and its diagnostic efficacy was tested in the validation group. Results(1) A simple scoring system for the diagnosis of liver fibrosis called MDFS was established in the model group, and the dimensions of the system included sex, HBV-DNA, Fibroscan (FS) value and splenomegaly. In MDFS, male, HBV-DNA≥ 107 U/mL,FS value≥7.3 kPa, and splenomegaly were assigned 1 point, -2 points, 3 points, and 2 points respectively. (2) The best cut-off value in MDFS was 2 points.(3) ROC curve of the model group indicated that the specificity and sensitivity were 92.86% and 54.76% respectively, the area under curve(AUC) was 0.790, and the Youden index was 0.4762. In the validation group, the diagnostic cut-off value was over 2 points, and the sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 52.17%, 82.35%, 2.96, and 0.58 respectively. (4) The scoring results of MDFS for different traditional Chinese medical syndromes of CHB showed that the scores of blood stasis blocking collaterals > damp-heat accumulation > deficiency of spleen and kidney yang> liver depression and spleen deficiency = stagnation of liver Qi. Conclusion The MDFS diagnostic scoring system has medium efficiency. The specificity of MDFS is relatively high and MDFs has a relatively low misdiagnosis rate for the diagnosis of obvious hepatic fibrosis in CHB. The MDFS is expected to be a noninvasive and simple diagnosing way for hepatic fibrosis in CHB.

Objective To explore the influence of dexmedetomidine combined with sufentanil on postoperative analgesia effect and immune function for patients undergoing lower limb fracture surgery. Methods One hundred cases patients of lower limb fracture undergoing open reduction and internal fixation of elective surgery in our hospital from January 2016 to November 2016 were selected ( ASAⅠ-Ⅱgrade, male 51 cases and female 49 cases, 30-65 years old, 50-75 kg). All cases were randomly divided into sufentanil group (Group S) and dexmedetomidine combined with sufentanil group (Group DS) according to the random number table, who used patient-controlled intravenous analgesia (PCIA). The PCIA drug formulations of two groups were as followings: sufentanil group (Group S) used 3 μg/h sufentanil+ondansetron 16 mg, dissolved in 0.9%sodium chloride injection 100 ml;dexmedetomidine combined with sufentanil group (Group DS) used dexmedetomidine 0.1μg/(kg · h)+sufentanil 2μg/h+ondansetron 16 mg, dissolved in 0.9%sodium chloride injection 100 ml;background infusion rate was 2 ml/h, and loading dose was 2 ml. Dose for patient-controlled analgesia (PCA) was 0.5 ml, and locking time was 15 min. The changes of pain, MAP, HR , sedation scores were recorded at 4 h (T1), 8 h (T2), 24 h (T3) and 48 h (T4) after operation; nausea and vomiting, hypotension, bradycardia, respiratory depression and other adverse reactions were aslo recorded at the same time. At 10 min before induction of anesthesia (T0) and T1-T4 after operation, the CD3+, CD4+, CD8+and NK cell activity of peripheral blood T lymphocyte subsets were determined using flow cytometry, and CD4 +/CD8 + ratio was calculated. Results The levels of MAP and HR in DS group at each time point after operation were lower than those in group S (P<0.05), the level of visual analogue score (VAS) in DS group at different time points were significantly lower than those of s group: (1.8 ± 0.3) scores vs. (2.5 ± 0.5) scores, (1.1 ± 0.5) scores vs. (1.9 ± 0.3) scores, (1.0 ± 0.5) scores vs. (1.8 ± 0.5) scores, (0.8 ± 0.3) scores vs. (1.5 ± 0.6) scores (P < 0.05), Ramsay Sedation score was significantly higher than that of s group: (3.5 ± 0.3) scores vs. (2.4 ± 0.6) scores, (3.3 ± 0.5) scores vs. (2.5 ± 0.3) scores, (3.5 ± 0.6) scores vs. (2.3 ± 0.5) scores, (3.2 ± 0.4) scores vs. (2.2 ± 0.5)scores (P<0.05);nausea and vomiting occurred in two patients after the operation of group DS , which was significantly lower than that of S group (P<0.05);compared with those at T0, CD3+, CD4+, CD4+/CD8+and NK cells in the two groups of patients decreased significantly at the time of T1-T4 (P<0.05);The levels of CD3+, CD4+, CD4+/CD8+and NK cells were significantly higher in group DS at T1- T4 than those in group S(P < 0.05). Conclusions Dexmedetomidine combined with sufentanil for analgesia in patients with lower limb fracture surgery has better effect. It decreases the incidence of nausea and vomiting, and improves the cellular immune function of patients.