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.

Janus kinase (JAK) and histone deacetylase (HDAC) referred to as crucial targets in autoimmune diseases and cancers have achieved quite success in the treatment of these diseases. Until now, several JAK and HDAC inhibitors have been approved. Recently, developing single multi-targeting inhibitors including JAK/HDAC dual inhibitors based on network pharmacology has made significant progress in improving therapeutic efficacy, reducing toxic and side effects, and overcoming drug resistance. In this review, we summarize novel JAK/HDAC dual inhibitors as well as JAK/HDAC-based triple-targeting inhibitors, in order to provide reference for the discovery of novel JAK/HDAC dual inhibitor.

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis

Objective: To investigate the epidemiology and hospitalization costs of pediatric community-acquired pneumonia (CAP) in Shanghai. Methods: A retrospective case summary was conducted on 63 614 hospitalized children with CAP in 59 public hospitals in Shanghai from January 2018 to December 2020. These children's medical records, including their basic information, diagnosis, procedures, and costs, were extracted. According to the medical institutions they were admitted, the patients were divided into the children's hospital group, the tertiary general hospital group and the secondary hospital group; according to the age, they were divided into <1 year old group, 1-<3 years old group, 3-<6 years old group, 6-<12 years old group and 12-18 years old group; according to the CAP severity, they were divided into severe pneumonia group and non-severe pneumonia group; according to whether an operation was conducted, the patients were divided into the operation group and the non-operation group. The epidemiological characteristics and hospitalization costs were compared among the groups. The χ² test or Wilcoxon rank sum test was used for the comparisons between two groups as appropriate, and the Kruskal-Wallis H test was conducted for comparisons among multiple groups. Results: A total of 63 614 hospitalized children with CAP were enrolled, including 34 243 males and 29 371 females. Their visiting age was 4 (2, 6) years. The length of stay was 6 (5, 8) days. There were 17 974 cases(28.3%) in the secondary hospital group, 35 331 cases (55.5%) in the tertiary general hospital group and 10 309 cases (16.2%) in the children's hospital group. Compared with the hospitalizations cases in 2018 (27 943), the cases in 2019 (29 009) increased by 3.8% (1 066/27 943), while sharply declined by 76.2% (21 281/27 943) in 2020 (6 662). There were significant differences in the proportion of patients from other provinces and severe pneumonia cases, and the hospitalization costs among the children's hospital, secondary hospital and tertiary general hospital (7 146 cases(69.3%) vs. 2 202 cases (12.3%) vs. 9 598 cases (27.2%), 6 929 cases (67.2%) vs. 2 270 cases (12.6%) vs. 9 397 cases (26.6%), 8 304 (6 261, 11 219) vs. 1 882 (1 304, 2 796) vs. 3 195 (2 364, 4 352) CNY, χ²=10 462.50, 9 702.26, 28 037.23, all P<0.001). The annual total hospitalization costs of pediatric CAP from 2018 to 2020 were 110 million CNY, 130 million CNY and 40 million CNY, respectively. And the cost for each hospitalization increased year by year, which was 2 940 (1 939, 4 438), 3 215 (2 126, 5 011) and 3 673 (2 274, 6 975) CNY, respectively. There were also significant differences in the hospitalization expenses in the different age groups of <1 year old, 1-<3 years old, 3-<6 years old, 6-<12 years old and 12-18 years old (5 941 (2 787, 9 247) vs. 2 793 (1 803, 4 336) vs. 3 013 (2 070, 4 329) vs. 3 473 (2 400, 5 097) vs. 4 290 (2 837, 7 314) CNY, χ²=3 462.39, P<0.001). The hospitalization cost of severe pneumonia was significantly higher than that of non-severe cases (5 076 (3 250, 8 364) vs. 2 685 (1 780, 3 843) CNY, Z=109.77, P<0.001). The cost of patients who received operation was significantly higher than that of whom did not (10 040 (4 583, 14 308) vs. 3 083 (2 025, 4 747) CNY, Z=44.46, P<0.001). Conclusions: The number of children hospitalized with CAP in Shanghai decreased significantly in 2020 was significantly lower than that in 2018 and 2019.The proportion of patients from other provinces and with severe pneumonia are mainly admitted in children's hospitals. Hospitalization costs are higher in children's hospitals, and also for children younger than 1 year old, severe cases and patients undergoing operations.
Infant ; Female ; Male ; Humans ; Child ; Retrospective Studies ; China/epidemiology* ; Hospitalization ; Community-Acquired Infections/therapy* ; Hospitals, Pediatric ; Pneumonia/therapy*

[摘 要] 目的：采用基于中国人群单核苷酸多态性位点开发的同源重组缺陷（HRD）检测工具评估云南地区卵巢癌患者的HRD状态和BRCA1/2基因突变频率并探讨其临床意义。方法：共纳入2021年1月至2023年5月间在云南省肿瘤医院收治的卵巢癌患者248例，HRD状态采用基因组瘢痕评分法（GSS）（主要依据拷贝数的长度、类型、位置及基因组断片）或HRD评分法（杂合性缺失、端粒等位基因失衡及大片段移位等基因组不稳定事件的总和）进行评估，当组织样本的GSS≥50分或HRD评分≥42分者或检测到有害的BRCA1/2基因突变时HRD被定义为阳性。分析患者HRD状态与临床病理特征的关系。结果：248名卵巢癌患者中70.97%的患者HRD呈阳性，其中BRCA1/2基因突变率为30.65%。Ⅲ~Ⅵ期、高级别浆液腺癌的卵巢癌患者具有更高的HRD阳性率（均P<0.01），HRD评分更高的患者其合并其他基因突变的频率也越高（P<0.05）。HRD状态与卵巢癌的病理类型、临床分期和其他基因突变均有关联（均P<0.01）。结论：云南地区卵巢癌患者HRD阳性率较高，HRD阳性的卵巢癌患者可以从聚ADP核糖聚合酶（PARP）抑制剂治疗中获得更大的收益。

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 effect of Danggui Jixueteng decoction(DJD)on bone marrow hematopoietic function in aplastic anemia(AA)model rats.Methods SD rats were randomly divided into blank group(0.9％NaCl),model group(0.9％NaCl),positive control group(10.8 g·kg-1 Fufang E Jiao Jiang),experimental-H,-M,-L groups(3.10,6.21,12.42 g·kg-1 DJD).AA rat model was established by acetophenylhydrazine combined with cyclophosphamide,and the model was administered at the same time,once a day for 15 days.Body mass,blood routine and hematopoietic factors in bone marrow were determined.Bone marrow smears of rats were observed and bone marrow nucleated cells were counted.Results The amounts of white blood cells in blood routine of experimental-M,experimental-H,positive control,model and blank groups were(2.44±0.46)× 109,(4.26±0.38)×109,(4.57±1.43)×109,(0.96±0.18)×109 and(9.83±0.87)×109·L-1;the amounts of red blood cells were(3.14±0.61)×1012,(3.44±0.35)×1012,(4.06±0.86)×1012,(1.35±0.54)×1012 and(9.61±1.18)×1012·L-1;the amounts of hemoglobin were(87.83±7.25),(108.17±8.93),(99.50±13.81),(22.33±7.63)and(153.92±19.42)g·L-1;the amounts of platelets were(218.50±28.05)×109,(291.83±32.32)×109,(269.33±67.60)×109,(37.50±12.21)×109 and(507.83±181.01)×109·L-1;granulocyte macrophage colony stimulating factor levels in bone marrow were(317.08±31.86),(359.70±36.37),(394.86±23.41),(198.31±14.63)and(379.39±14.95)ng·L-1;vascular endothelial cell adhesion molecule 1 levels were(765.98±60.32),(877.96±24.75),(812.74±66.40),(588.25±58.15)and(929.01±35.50)μg·L-1;interleukin 3 levels were(129.42±6.19),(121.31±12.65),(124.24±2.50),(83.24±11.05),(135.67±7.66)ng·L-1;Caspase-3 levels were(105.49±10.07),(115.49±6.89),(114.36±2.97),(150.62±16.82)and(116.10±4.68)pmol·L-1;the bone marrow injury scores were(1.31±0.18),(1.96±0.09),(1.49±20.42),(3.76±0.19)and(0.05±0.04);the numbers of nucleated cells were(5.79±0.47)×106,(5.12±0.10)×106,(5.56±0.25)×106,(3.20±0.28)×106 and(8.49±0.56)×106·L-1,respectively.Compared with model group,there were significant differences in the experimental-M,-H groups,positive control group,and blank group(P＜0.05,P＜0.01).Conclusion DJD may improve bone marrow hematopoietic function of AA model rats by regulating bone marrow hematopoietic microenvironment,improving immune function and inhibiting apoptosis.

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases

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.