Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To explore the value of intensity ratio(IR)of lesion to non-tumor liver parenchyma on contrast-enhanced ultrasound(CEUS)Kupffer phase for differentiating hepatocellular carcinoma(HCC)and intrahepatic cholangiocarcinoma(IHC)/metastatic liver carcinoma.Methods Totally 54 patients with HCC(HCC group),30 with IHC and 51 with liver metastatic carcinoma(non-HCC group)diagnosed by pathology were retrospectively enrolled.Quantitative parameters derived from CEUS time-intensity curves,including peak intensity(PI),time to peak(TTP),wash-in area under the curve(WiAUC),wash-out area under the curve(WoAUC),wash-in and wash-out area under the curve(WiWoAUC)of lesion in vascular phase and IR of lesion to non-tumor liver parenchyma in Kupffer phase were compared between groups,and a combined diagnostic model was established based on parameters being significantly different between groups using binary logistic regression analysis.Receiver operating characteristic(ROC)curves were plotted,and the area under the curves(AUC)were calculated to evaluate the efficacy of each CEUS parameter alone and the combined model for differentiating HCC and IHC/liver metastatic carcinoma.Results In HCC group,PI,WoAUC and WiWoAUC were all higher(all P＜0.001),while IR was significantly lower than those in non-HCC group(P＜0.001).The AUC of PI,WoAUC,WiWoAUC and IR for differentiating HCC and IHC/metastatic liver carcinoma was 0.673,0.741,0.738 and 0.736,respectively,all lower than that of combined model(0.862,all P＜0.05).Conclusion IR of lesion to non-tumor liver parenchyma on CEUS Kupffer phase could be used to differentiate HCC and IHC/metastatic liver carcinoma.Combining with quantitative parameters on CEUS vascular phase could improve differentiating efficiency.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective To investigate the relationships of the mRNA expression levels of mitochon-drial ribosomal large subunit protein 13(MRPL13),BCL2-associated protein A1(BCL2A1)and TP53 apoptosis-inducing protein 1(TP53AIP1)in the serum of breast cancer patients with their chemotherapy efficacy as well as immune function.Methods A total of 148 triple-negative breast cancer patients undergoing chemotherapy were selected as the study subjects.Based on chemotherapy efficacy,they were divided into responsive group(97 cases)and non-responsive group(51 cases).Sixty healthy individuals undergoing physical examinations during the same period were selected as the control group.The mRNA expression levels of MRPL13,BCL2A1 and TP53AIP1 in the serum of patients were detected.The concentrations of immunoglobulin M(IgM),immunoglobulin G(IgG)and im-munoglobulin A(IgA)in the serum of patients were measured,and the proportions of CD4+and CD8+cells in whole blood were determined.The mRNA expression levels of MRPL13,BCL2A1 and TP53AIP1 were compared between the breast cancer group and the control group.The mRNA ex-pression levels of MRPL13,BCL2A1 and TP53AIP1 were compared between the responsive and non-responsive groups.The differences in immune function indicators before and after chemotherapy be-tween the responsive and non-responsive groups,were compared.The correlations of the mRNA ex-pression levels of MRPL13,BCL2A1 and TP53AIP1 with immune indicators were analyzed.Factors influencing chemotherapy efficacy were screened.Results The mRNA expression levels of MRPL13 and BCL2A1 in the breast cancer group were higher than those in the control group,while the mRNA expression level of TP53AIP1 was lower,with statistically significant differences(P＜0.05).In the responsive group,the mRNA expression levels of MRPL13 and BCL2A1 were lower than those in the non-responsive group,while the mRNA expression level of TP53AIP1 was higher,with statistically significant differences(P＜0.05).After chemotherapy,the IgM concentration in the responsive group was higher than that in the non-responsive group,with a statistically significant difference(P＜0.05).The proportion of CD8+cells in the responsive group was lower than that in the non-responsive group,with a statistically significant difference(P＜0.05).The mRNA expres-sion level of MRPL13 was positively correlated with IgM,IgG and CD8+(r=0.672,0.716,0.824,P＜0.05).The mRNA expression level of BCL2A1 was positively correlated with IgA and CD4+(r=0.654,0.862,P＜0.05).The mRNA expression level of TP53AIP1 was negatively cor-related with CD4+and CD8+(r=-0.846,-0.792,P＜0.05).High expressions of MRPL13 and BCL2A1 were independent risk factors for chemotherapy efficacy in breast cancer patients(P＜0.05),while high expression of TP53AIP1 was protective factor(P＜0.05).Conclusion The mRNA expression levels of MRPL13,BCL2A1 and TP53AIP1 in the serum of triple-negative breast cancer patients undergoing chemotherapy are correlated with the levels of IgM,IgG and IgA,the proportions of CD4+and CD8+T cells,and chemotherapy efficacy.High expression of MRPL13 and BCL2A1 are independent risk factors for poor chemotherapy efficacy,while high expression of TP53AIP1 is a protective factor.

Objective:To improve the understanding of patients with diffuse large B-cell lymphoma (DLBCL) with pulmonary cryptococcosis.Methods:The clinical data of 1 DLBCL patient with pulmonary cryptococcosis in the Central Hospital of Fengxian District of Shanghai in May 2023 were retrospectively analyzed, and the relevant literatures were reviewed.Results:This 75-year-old female patient was asymptomatic after 2 cycles of R-CHOP chemotherapy. The high-resolution CT of lung showed that lung nodules were progressively enlarged. Antibacterial treatment was ineffective. Pulmonary cryptococcosis was confirmed by bronchoalveolar lavage fluid (BALF) targeted high-throughput sequencing (tNGS) and cryptococcus capsular antigen (CrAg) detection. The central nervous system was not involved. And the long-term adequate-dose fluconazole was prescribed for 6 months, and the treatment against lymphoma was given synchronously. The lung nodule lesions reduced after antifungal therapy for 1 month. The lung nodules disappeared after the follow-up of 6 months after completion of final chemotherapy. The evaluation of lymphoma indicated complete remission.Conclusions:Pulmonary cryptococcosis occurs insidiously and shows no specific symptoms; its imaging manifestations are variable and routine anti-infection is ineffective. Immunochemotherapy for lymphoma patients is a high-risk factor for cryptococcal infection. tNGS and CrAg testing for BALF are effective methods of the confirmed diagnosis. The early and long-term adequate-dose antifungal treatment is the key to preventing the recurrence or progression.

Objective To investigate the cerebral protective role of Duzhi pills on ischemic stroke rats and its mechanisms.Methods The healthy male SD rats were assigned to 5 groups:sham group,model group,Duzhi pill low-dose group(1.0 g/kg a day),Duzhi pill high-dose group(2.0 g/kg a day),or argatroban group(positive control).The low-dose and high-dose groups of Duzhi pills were intragastrically administered once a day for 8 d,while the other groups were intragastrically administered with the same amount of normal saline.Except the sham group,the middle cerebral artery occlusion(MCAO)cerebral ischemia-reperfusion model was established by suture method at 0.5 h after intragastric administration on the 8th day in other groups,and the ischemia duration was 90 min.Argatroban group was given a single dose(3.0 mg/kg)of argatroban via caudal vein at the same time of reperfusion.After 24 h of cerebral ischemia,the area of cerebral infarction,degree of cerebral infarction and neurological function injury were evaluated by 2,3,5-triphenyltetrazolium chloride(TTC)staining,Nissl staining and neurobehavioral score,respectively.The levels of inflammatory factors(transforming growth factor-β1[TGF-β1]and interleukin-1β[IL-1β])in the brain after cerebral ischemia were detected by enzyme-linked immunosorbent assay(ELISA),and the coagulation indexes were detected by an automatic coagulation analyzer.The scavenging ability of Duzhi pills on free radicals was analyzed by 2,2-diphenyl-1-picrylhydrazyl(DPPH)scavenging experiment.Results High-dose Duzhi pills reduced the cerebral infarction area,decreased the deep Nissl staining score of neural cells,and improved the symptoms of neurobehavioral defects in MCAO rats(compared with the model group,all P＜0.01).The levels of IL-1β and TGF-β1 in the ischemic brain tissue of the model group were significantly increased(compared with the sham group,both P＜0.01),while the levels of IL-1β and TGF-β1 in the brain tissue of the rats treated with low-dose and high-dose Duzhi pills were significantly decreased(compared with the model group,all P＜0.01).The coagulation index fibrinogen level in the model group was significantly higher than that in the sham group(P＜0.01),and both low-dose and high-dose Duzhi pills could inhibit the production of fibrinogen(compared with the model group,both P＜0.01).DPPH scavenging test results showed that Duzhi pills could scavenge free radical,the half inhibitory concentration was(1.33±1.11)mg/mL,and the slope of the curve was 1.378±0.145.Conclusion Duzhi pills play a cerebral protective role in ischemic stroke rats.The mechanism may be related to the inhibition of fibrinogen production,the reduction of inflammatory factors(TGF-β1 and IL-1β),and the antioxidant effects.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.