Objective: To observe the influence of epidermal growth factor tyrosine kinase inhibitors (EGFR-TKIs) on peripheral blood T lymphocyte subsets, and its efficacy and safety in the treatment of non-small cell lung cancer (NSCLC) patients.Methods: A total of 35 cases with NSCLC in our hospital were selected as the observation group and 28 healthy persons undergoing health examination at the same time were used as the control group.All the NSCLC patients were with EGFR mutations and accepted the EGFR-TKIs therapy.Flow cytometry was employed to detect T lymphocyte subsets in peripherial blood (including CD3+,CD4+,CD8+,CD4+/CD8+ and NK lymphocy-tes)in one week before the treatment, at the 1st, 2nd and 4th cycle after the EGFR-TKIs treatment, and the curative effect and safety were evaluated as well.Results: Before the chemotherapy, the levels of CD3+, CD4+, CD4+/CD8+ and NK lymphocytes in the NSCLC patients were significantly lower than those in the control group (P<0.01), and CD8+ lymphocytes increased significantly (P<0.01).After the treatment of 1, 2 and 4 cycles, the levels of CD4+and CD4+/CD8+ increased in varying degrees when compared with those before the treatment (P<0.01), and CD8+ decreased significantly when compared with that before the treatment (P<0.01).After the treatment of 2 and 4 cycles, NK cells increased in varying degrees when compared with those before the treatment (P<0.05).After the treatment of 4 cycles, the level of CD3+lymphocytes was significantly higher than that before the treatment (P<0.05).The T lymphocyte immune function in the patients with different therapeutic effects showed statistically significant difference (P<0.05).The order of lymphocyte subgroup improvement was PR>SD>PD.The adverse reactions caused by EGFR-TKIs were slight, and all could be improved markedly after the symptomatic treatment.Conclusion: EGFR-TKIs can significantly regulate the expression of T lymphocyte subsets in NSCLC patients and improve the immune function of the patients with promising safety.

Objective To investigate the diagnostic value of diffusion weighted imaging(DWI)-based radiomics model to identify small hepatocellular carcinoma(＜2 cm)(SHCC)and dysplastic nodule(DN)in the background of hepatitis cirrhosis.Methods A total of 93 cases SHCC and 25 cases with DN with complete enhanced MRI images and surgically pathologically confirmed were collected retrospectively.Chi-square test was performed to analyze the signal characteristics of DWI and enhanced triphasic MRI images between the two groups.ITK-SNAP was used to draw the region of interest(ROI)on DWI,and FAE software was applied for extraction,selec-tion,and construction of support vector machine(SVM)models(dividing into training set and test set according to the ratio of 7∶3).The diagnostic performance of model was evaluated by receiver operating characteristic(ROC)curve.Results There were statisti-cally significant differences in enhanced triphasic MRI and DWI between SHCC and DN(P＜0.05).The area under the curve(AUC)of the DWI-SVM model training set was 0.936,and sensitivity,specificity and accuracy was 95.4％,88.2％and 93.9％,respec-tively,and the AUC of the test set was 0.911,and sensitivity,specificity and accuracy was 85.7％,87.5％and 86.1％,respectively,which were all significantly better than the diagnostic efficacy of DWI(AUC=0.720).Conclusion DWI-SVM model with signifi-cantly higher AUC and specificity can effectively differentiate SHCC from DN in the background of hepatitis cirrhosis.

Objective:The current study aimed to evaluate the possible protective effects of N-acetylcysteine (NAC) against Indum-tin oxide (ITO) nanoparticle (Nano-ITO) -induced pulmonary alveolar proteinosis (PAP) in rats, especially via modulation of nuclear factor kappa B (NF-κB) signaling.Methods:In October 2019, 50 adult male Sprague-Dawley rats were randomly allocated into five groups (10 rats each) as follows: blank control group, saline control group, NAC control group (200 mg/kg), Nano-ITO group (receiving a repeated intratracheal dose of 6 mg/kg Nano-ITO) and NAC intervention group (pre-treated intraperitoneally with 200 mg/kg NAC 1.5 h before the administration of an intratracheal dose of 6 mg/kg Nano-ITO). The rats were exposed twice a week for 12 weeks. Rats were then euthanized under anesthesia, and their lungs were removed for histopathological and immunohistochemical analysis. The comparison of indicators reflecting oxidative stress and pulmonary inflammation among groups was conducted using one-way analysis of variance (ANOVA) and Bonferroni's test. The effect of NAC on Nano-ITO induced NF-κB signaling pathway in rats was analyzed.Results:Histopathological examination of Nano-ITO exposed rats revealed diffuse alveolar damage, including PAP, cholesterol crystals, alveolar fibrosis, pulmonary fibrosis, and alveolar emphysema. Immunohistochemical results of Nano-ITO exposed rats showed strong positive for nuclear factor κB p65 (NF-κB p65) and nuclear factor Kappa B inhibitory factor kinase (IKK-β) and weak positive for nuclear factor κB inhibitory protein α (IκB-α) in the nuclei of bronchiolar and alveolar epithelial cells. Compared with blank control group, saline control group and NAC control group, the level of total protein (TP) in bronchoalveolar lavage fluid of rats in Nano-ITO group was significantly increased ( P<0.05), and the activities of lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) were significantly increased ( P<0.05), the levels of proinflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were significantly increased ( P<0.05), and the levels of NF-κB p65, IKK-β, inducible nitric oxide synthase (iNOS) and reactive oxygen species (ROS) in lung tissue were significantly increased ( P<0.05). Compared with Nano-ITO group, the levels of TP, T-AOC, MDA and TNF-α in bronchoalveolar lavage fluid of rats in NAC intervention group were significantly decreased ( P<0.05), and the levels of NF-κB p65 and ROS in lung tissue were significantly decreased (P<0.05). Western blot results showed that compared with the control groups, the protein expressions of NF-κB p65 and IKK-β in the lung tissue of Nano-ITO group were increased, while the protein expression of IκB-α was decreased ( P<0.05). Compared with Nano-ITO group, the protein expressions of NF-κB p65 and IKK-β in lung tissue of rats in NAC intervention group were decreased, while the protein expression of IκB-α was increased ( P<0.05) . Conclusion:The study demonstrated that Nano-ITO might induce pulmonary toxicity through the activation of NF-κB signaling pathway, and NAC could antagonize the pulmonary toxicity of Nano-ITO by inhibiting the NF-κB signaling pathway.

Objective:The current study aimed to evaluate the possible protective effects of N-acetylcysteine (NAC) against Indum-tin oxide (ITO) nanoparticle (Nano-ITO) -induced pulmonary alveolar proteinosis (PAP) in rats, especially via modulation of nuclear factor kappa B (NF-κB) signaling.Methods:In October 2019, 50 adult male Sprague-Dawley rats were randomly allocated into five groups (10 rats each) as follows: blank control group, saline control group, NAC control group (200 mg/kg), Nano-ITO group (receiving a repeated intratracheal dose of 6 mg/kg Nano-ITO) and NAC intervention group (pre-treated intraperitoneally with 200 mg/kg NAC 1.5 h before the administration of an intratracheal dose of 6 mg/kg Nano-ITO). The rats were exposed twice a week for 12 weeks. Rats were then euthanized under anesthesia, and their lungs were removed for histopathological and immunohistochemical analysis. The comparison of indicators reflecting oxidative stress and pulmonary inflammation among groups was conducted using one-way analysis of variance (ANOVA) and Bonferroni's test. The effect of NAC on Nano-ITO induced NF-κB signaling pathway in rats was analyzed.Results:Histopathological examination of Nano-ITO exposed rats revealed diffuse alveolar damage, including PAP, cholesterol crystals, alveolar fibrosis, pulmonary fibrosis, and alveolar emphysema. Immunohistochemical results of Nano-ITO exposed rats showed strong positive for nuclear factor κB p65 (NF-κB p65) and nuclear factor Kappa B inhibitory factor kinase (IKK-β) and weak positive for nuclear factor κB inhibitory protein α (IκB-α) in the nuclei of bronchiolar and alveolar epithelial cells. Compared with blank control group, saline control group and NAC control group, the level of total protein (TP) in bronchoalveolar lavage fluid of rats in Nano-ITO group was significantly increased ( P<0.05), and the activities of lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) were significantly increased ( P<0.05), the levels of proinflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were significantly increased ( P<0.05), and the levels of NF-κB p65, IKK-β, inducible nitric oxide synthase (iNOS) and reactive oxygen species (ROS) in lung tissue were significantly increased ( P<0.05). Compared with Nano-ITO group, the levels of TP, T-AOC, MDA and TNF-α in bronchoalveolar lavage fluid of rats in NAC intervention group were significantly decreased ( P<0.05), and the levels of NF-κB p65 and ROS in lung tissue were significantly decreased (P<0.05). Western blot results showed that compared with the control groups, the protein expressions of NF-κB p65 and IKK-β in the lung tissue of Nano-ITO group were increased, while the protein expression of IκB-α was decreased ( P<0.05). Compared with Nano-ITO group, the protein expressions of NF-κB p65 and IKK-β in lung tissue of rats in NAC intervention group were decreased, while the protein expression of IκB-α was increased ( P<0.05) . Conclusion:The study demonstrated that Nano-ITO might induce pulmonary toxicity through the activation of NF-κB signaling pathway, and NAC could antagonize the pulmonary toxicity of Nano-ITO by inhibiting the NF-κB signaling pathway.

Objective: To investigate the influence of pharmaceutical care pathway on cancer-related fatigue (CRF) and negative emotion in patients with advanced lung cancer undergoing chemotherapy. Methods: Patients with advanced lung cancer admitted to the oncology department of Yongkang first people′s hospital from January 2017 to June 2018 for chemotherapy were randomly divided into two groups:61 cases received conventional clinical pathway management (control group), and 64 cases received conventional clinical pathway combined with pharmaceutical pathway management (intervention group). Fatigue, anxiety, depression scores were compared between the two groups before and after 2, 4 cycles chemotherapy. Results: There was no significant difference in baseline condition between the two groups (P>0.05). After 4 cycles of chemotherapy, emotional, physical and cognitive fatigue scores in the intervention group were lower than control group (t=2.975, 1.512, 2.393, P<0.05). With the increase of chemotherapy cycles, scores of fatigue dimensions in control group were increased (F=44.274,21.740,29.261,7.206, P<0.05). In the intervention group, there were statistically significant differences in scores of fatigue dimensions (F=17.083, 15.902, 17.055, 10.543, P<0.01), among which, scores of behavioral and physical fatigue dimensions were increased (P<0.01), while scores of emotional and cognitive fatigue dimensions were decreased (P<0.01). In terms of negative emotions, depression scores in the intervention group were lower than those in control group at 2 cycles of chemotherapy (t=2.578, P<0.05), and at 4 cycles, anxiety and depression scores were lower than control group (t=7.004, 7.454, P<0.05). As the chemotherapy cycle increased, anxiety and depression scores in the control group increased (F=12.333, 14.819, P<0.05), while those in the intervention group decreased (F=4.992, 3.826, P<0.05). Conclusion The pathway of clinical pharmaceutical care can significantly improve the CRF and negative emotions of patients with advanced lung cancer undergoing chemotherapy.

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 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 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 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.