Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

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 carry out genetic testing for 3 fetuses with abnormal prenatal screening. METHODS: Fetal ultrasound, karyotype analysis, single nucleotide polymorphism (SNP) array and fluorescence in situ hybridization were performed. RESULTS: Abnormalities of chromosome 22 were found with all 3 fetuses. Fetus 1 harbored a 7.1 Mb deletion in 22q13.2q13.33 region, which involved 54 OMIM genes including SHANK3 and FBLN1. Fetus 2 had a mosaicism karyotype, with 12% of cells harboring a 6.6 Mb deletion in 22q13.31q13.33, covering 48 OMIM genes such as SHANK3 and PPARA, and 5% of cells harboring a 26.1 Mb duplication in 22q11.1q13.2 involving 285 OMIM genes. Fetus 3 carried a tandem duplication of 1.7 Mb in 22q11.1q11.21, which involved 10 OMIM genes including CECR1, CECR2 and ATP6V1E1. No abnormality was found in the three couples by chromosomal karyotyping and SNP array analysis. CONCLUSION The severity of diseases caused by chromosome 22 abnormalities not only depends on the range of the deletion or duplication, but is also closely related to chromosome structure, gene dose and genetic environment. Combined ultrasonography and various genetic testing techniques in prenatal diagnosis can greatly increase the detection rate of genetic diseases with substantial phenotypic variation.
Chromosome Aberrations ; Chromosome Deletion ; Chromosome Disorders ; diagnosis ; genetics ; Chromosomes, Human, Pair 22 ; genetics ; Female ; Fetus ; Genetic Testing ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Pregnancy ; Prenatal Diagnosis ; Transcription Factors ; Ultrasonography, Prenatal

Objective: To explore the clinical significance of a prenatal case with two small supernumerary marker chromosomes (sSMC) through identification of their origins. Methods: G-banding chromosomal karyotyping analysis were carried out on fetal amniotic fluid sample and peripheral blood samples from both patients. Fluorescence in situ hybridization (FISH) and single nucleotide polymorphism-array (SNP-array) were used to analyze the component and size of the sSMCs. Results: The karyotype of the fetus was determined as 47, XX, + mar[53]/48, XX, + 2 mar[31]/46, XX[14]. SNP-array has revealed four copies of chromosome 2q11.1q11.2 with a size of 2.6 Mb and three copies of 10p11.23q11.23 with a size of 20.6 Mb. The results was confirmed by FISH. Conclusion A rare chromosomal abnormality with two sSMCs was identified by combined karyotype analysis, SNP-array and FISH, which provided valuable information for prenatal diagnosis.

Objective To investigate the clinical efficacy of primary closure in laparoscopic common bile duct exploration (LCBDE).Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 2 429 patients who underwent primary closure in LCBDE in the Second Hospital of Chengdu City from March 1992 to December 2017 were collected.Patients underwent laparoscopic cholecystectomy (LC) + stone extraction using LCBDE or extracorporeal shock wave lithotripsy (ESWL),laparoscopic endoscopic sphincteropapillotomy (LEST) was performed selectively,then underwent laparoscopic endoscopic nasobiliary drainage (LENBD) or laparoscopic transabdominal antegrade-guide common bile duct stent implantation,finally underwent primary closure of common bile duct.Observation indicators:(1) surgical situations;(2) postoperative recovery;(3) postoperative short-term complications;(4) follow-up situation.Follow-up using outpatient examination and telephone interview was performed to observe long-term surgical complications once every 3 months up to 1 year postoperatively.Measurement data with normal distribution were represented as (x) ± s.Measurement data with skewed distribution were described as M (range).Results (1) Surgical situations:of 2 429 patients,2 251 underwent successful stone extraction using LCBDE,relief of the obstruction and primary closure of common bile duct,with depletion of stones;15 underwent stone extraction using conversion to open surgery,with depletion of stones;163 had residual stones or surgery-related complications.Of 2 429 patients,1 144,898,223,110 and 54 were respectively detected in grade N or 0,1,2,3 and 4 of laparoscopic distal of the common bile duct smooth classification (LDSC);599 underwent LEST,367 underwent LENBD,207 indwelled urinary catheter through cystic duct stump,125 underwent laparoscopic transabdominal antegrade-guide common bile duct stent implantation and 1 131 underwent primary closure in LCBDE only.Number of removing the stones,diameter of common bile duct,volume of intraoperative blood loss and operation time was (2.5±0.2)per case,(0.7±0.4)cm,(22.4±2.6)mL and (100±12) minutes,respectively.(2) Postoperative recovery:time of postoperative gastrointestinal function recovery,duration of hospital stay and treatment expenses were respectively (2.5±0.5) days,(7.3± 1.2) days and (2.7±0.3) × 104 yuan.Of 2 429 patients,367 removed nasobiliary catheter at 3-7 days postoperatively,207 removed urinary catheter at 3-6 weeks postoperatively,and 125 removed common bile duct stent through duodenoscope port at 1-4 months postoperatively.(3) Postoperative short-term complications:incidence of postoperative short-term complications in 2 429 patients was 6.711％ (163/2 429).① Ninety-four patients with bile leakage were cured after drainage and symptomatic and supportive treatment.② Of 29 patients with residual stones:25 with residual stones of common bile duct were cured by stone extraction using endoscopic sphincterotomy of duodenal papilla,and 4 with residual stones of intrahepatic bile duct didn't receive treatment.③ One patient died at 15 days after surgery for pancreatic cancer.④ Of 39 with postoperative other complications:2 with postoperative hemorrhage were cured by laparoscopic reoperation;12,19 and 3 were respectively complicated with postoperative inflammatory stenosis of duodenal papilla induced to short-term obstructive jaundice,mild acute pancreatitis and stress ulcer bleeding of upper digestive tract,and they were improved by endoscopy or non-operation treatment;2 with stenosis of bile duct didn't receive treatment;1 had a miss ligation at bending section of front zone of nasobiliary catheter,and ligation was removed by endoscopic retrograde cannulation of the pancreatic at 19 days postoperatively.(4) Follow-up situation:of 2 429 patients,1 749 were followed up for 3-12 months,with a median time of 6 months.During the follow-up,of 1 749 patients,2 had mild stenosis in the primary closure area of common bile duct incision and 1 had stenosis of duodenal papilla,they were not treated,and other patients didn't have related complications.Conclusion Controlling strictly the operative indication,primary closure of common bile duct in LCBDE is safe and feasible,with satisfactory clinical outcomes.