Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Objective:To explore the risk factors affecting the survival and efficacy of patients with acute myeloid leukemia with myelodysplasia-related changes(AML-MRC)transformed from myelodysplastic syndrome(MDS).Methods:The clinical data of 60 patients with AML-MRC transformed from MDS who hospitalized in The Third Affiliated Hospital of Soochow University from January 2010 to December 2021 were retrospectively analyzed.The demographic data and laboratory parameters,cytogenetic karyotypes,target genes of AML detected by next generation sequence,risk stratification,treatment regimen,therapeutic efficacy and survival outcome were documented.Rank sum test and Chi-square test or Fisher exact test were used to compare the survival and efficacy.The effects of clinical parameters,risk stratification and treatment regimens on the survival and efficacy of the AML-MRC patients were analyzed by univariate and multivariate analysis.Results:The median overall survival(OS)of the AML-MRC patients was 4.5 months,the 1-year OS rate was 28.3％,and the complete remission(CR)rate after treatment was 33.3％.The univariate analysis showed that age≥60 years,leukocytosis,severe thrombocytopenia,poor-risk group and only accepted hypomethylating agents(HMAs)or supportive therapy were the risk factors affecting OS.COX multivariate analysis showed that thrombocytopenia(HR=4.46),HMAs therapy(compared to transplantation,HR=10.47),supportive therapy(compared to transplantation,HR=25.80)and poor-risk group(compared to medium-risk group,HR=13.86)were independent hazard factors for median OS of patients with AML-MRC.The univariate analysis showed that the risk factors affecting 1-year OS in patients with AML-MRC were age ≥ 60 years,thrombocytopenia,time of transformation from MDS to AML(TTA)≥3 months,fibrinogen-albumin ratio index(FARI)≥ 0.07,CONUT score≥5,poor-risk group and supportive therapy.Binary logistic regression analysis showed that the independent risk factors for 1-year OS in AML-MRC patients were age ≥ 60 years(HR=11.23),thrombocytopenia(HR=8.71),FARI ≥ 0.07(HR=5.19)and poor-risk group(HR=14.00).The risk factors affecting CR of AML-MRC patients in univariate analysis were age ≥ 60 years,thrombocytopenia,FARI ≥ 0.1,CONUT score ≥ 5,poor-risk group and supportive therapy,while binary logistic regression analysis showed that age ≥ 60 years(HR=7.35),CONUT score ≥ 5(HR=9.60),thrombocytopenia(HR=12.05)and poor-risk group(HR=32.5)were independent risk factors affecting CR of the patients.Conclusion:The OS of AML-MRC patients is poor,old age(≥ 60 years old),supportive therapy,HMA therapy,poor-risk,thrombocytopenia,FARI ≥ 0.07 and CONUT score ≥ 5 may be associated with poor prognosis.

Objective:To explore and analyze the clinical features and prognostic factors of secondary intestinal diffuse large B-cell lymphoma(SI-DLBCL),in order to provide reference for the basic research and clinical diagnosis and treatment of secondary lymphoma of rare sites in the field of hematology.Methods:The clinical data of 138 patients with SI-DLBCL admitted to Fujian Medical University Union Hospital from June 2011 to June 2022 were collected and sorted,the clinical and pathological features,diagnosis,treatment and prognosis were analyzed.Cox regression risk model was used to conduct univariate and multivariate analysis on the prognostic risk factors.Results:Among the 138 patients with SI-DLBCL included in this study,85(61.59％)were male,53(38.41％)were female,the median age of onset was 59.5(16-84)years,the clinical manifestations lacked specificity,the first-line treatment regimen was mainly chemotherapy(67.39％),94 cases(68.12％)received chemotherapy alone,40 cases(28.98％)were treated with chemotherapy combined with surgery,and 4 cases(2.90％)were treated with surgery alone.The median follow-up time was 72(1-148)months.Among the 138 patients with SI-DLBCL,79(57.25％)survived,34(24.64％)died,25 cases(18.12％)lost to follow-up,the PFS rates of 1-year,3-year and 5-year were 57.97％,49.28％and 32.61％,and the OS rates of 1-year,3-year and 5-year were 60.14％,54.35％and 34.06％,respectively.The results of univariate Cox regression analysis showed that age,Lugano stage and IPI score were the influencing factors of OS in SI-DLBCL patients,and age,Lugano stage and IPI score were the influencing factors of PFS in SI-DLBCL patients.The results of multivariate Cox analysis showed that Lugano stage was an independent prognostic factor affecting OS and PFS in SI-DLBCL patients.Conclusion:Patients with SI-DLBCL are more common in middle-aged and elderly men,and the early clinical manifestations lack specificity,and the first-line treatment regimen is mainly R-CHOP chemotherapy,and Lugano stage is an independent prognostic factor affecting OS and PFS in SI-DLBCL patients.

Objective:To assess the deformation of the bladder-neck opening and the impact of the bladder-neck angle(BNA)on urination in male patients by fluid-structure interaction(FSI)analysis.Methods:We established geometric models of the blad-der,prostate and urethra were established,incorporating both normal and enlarged BNAs,and assessed the effects of BNA alteration on urinary flow by FSI simulation of the flow rate and pressure of the urine within the bladder,bladder neck and urethra,and that of pros-tate displacement as well.We retrospectively analyzed the clinical data on 145 male patients from the Second Hospital of Hebei Medical University between June 2020 and June 2023,39 with acute urine retention(the AUR group)and 106 without(the non-AUR group),and evaluate the impact of BNA on urination based on the urinary flow rate and prostate volume.Results:Comparative simulation a-nalysis showed significant differences in the total urethral pressure and flow rate between the normal and enlarged BNA models(P＜0.05).The maximum prostate displacement was found at the bladder neck,with moderate displacement and unchanged urethral diame-ter in the normal BNA model,but significant displacement and a reduced urethral opening diameter in the enlarged BNA model.FSI analysis confirmed an evident impact of enlarged BNA on urination,more significant in the AUR than in the non-AUR patients(P＜0.05).The BNAs in the patients with the maximum urinary flow rate(Qmax)of＜10,10-15 or＞15 ml/s were 83.7°±2.5°,67.5°±1.8° and 65.1°±4.8° respectively,with statistically significant difference between the former one and the latter two groups(P＜0.05).The BNAs in the patients with normal prostate volume or BPH of grade Ⅰ,Ⅱ,Ⅲ or Ⅳ were 65.0°±3.7°,67.2°±3.1°,71.5°±2.0°,82.8°±3.5° and 105.8°±6.0°,respectively(P＜0.05),with statistically significant difference between BPH grades Ⅲ and Ⅳ(P＜0.05)as well as between these two and the other three groups(P＜0.05),but not among the normal prostate volume,BPH grade Ⅰ and BPH grade Ⅱ groups(P＞0.05).Spearman correlation analysis indicated that BNA was strongly correlated with total prostate volume(TPV),transition zone volume(TZV),intravesical prostatic protrusion(IPP),prostatic urethral angle(PUA),IPSS,and Qmax(P＜0.05).Conclusion:Changes in BNA affect urination and are closely associated with the se-verity of prostate hyperplasia.The BNA may be an important anatomical factor for assessing the severity of lower urinary tract symptoms in BPH patients.

Objective To investigate the effects of α1-antitrypsin(AAT)on motor function in adult mice with immature brain white matter injury.Methods Five-day-old C57BL/6J mice were randomly assigned to the sham surgery group(n=27),hypoxia-ischemia(HI)+ saline group(n=27),and HI+AAT group(n=27).The HI white matter injury mouse model was established using HI methods.The HI+AAT group received intraperitoneal injections of AAT(50 mg/kg)24 hours before HI,immediately after HI,and 72 hours after HI;the HI+saline group received intraperitoneal injections of the same volume of saline at the corresponding time points.Brain T2-weighted magnetic resonance imaging scans were performed at 7 and 55 days after modeling.At 2 months of age,adult mice were evaluated for static,dynamic,and coordination parameters using the Catwalk gait analysis system.Results Compared to the sham surgery group,mice with HI injury showed high signal intensity on brain T2-weighted magnetic resonance imaging at 7 days after modeling,indicating significant white matter injury.The white matter injury persisted at 55 days after modeling.In comparison to the sham surgery group,the HI+saline group exhibited decreased paw print area,maximum contact area,average pressure,maximum pressure,paw print width,average velocity,body velocity,stride length,swing speed,percentage of gait pattern AA,and percentage of inter-limb coordination(left hind paw → left front paw)(P<0.05).The HI+saline group showed increased inter-paw distance,percentage of gait pattern AB,and percentage of phase lag(left front paw → left hind paw)compared to the sham surgery group(P<0.05).In comparison to the HI+saline group,the HI+ AAT group showed increased average velocity,body velocity,stride length,and swing speed(right front paw)(P<0.05).Conclusions The mice with immature brain white matter injury may exhibit significant motor dysfunction in adulthood,while the use of AAT can improve some aspects of their motor function.[Chinese Journal of Contemporary Pediatrics,2024,26(2):181-187]