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 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.

Objective:To investigate the diagnostic value of preoperative fine-needle aspiration (FNA) of lymph nodes combined with washout thyroglobulin testing (FNA-Tg) for detecting lymph node metastasis in papillary thyroid carcinoma (PTC).Methods:A prospective study was conducted on 112 patients diagnosed with PTC at Wenzhou Central Hospital from December 2021 to December 2023, all of whom had suspicious lateral cervical lymph node metastasis identified through preoperative ultrasound. All patients underwent lymph node FNA and FNA-Tg. The suspicious lymph nodes were surgically excised. The diagnostic efficacy of FNA, FNA-Tg, and the combination of FNA and FNA-Tg for PTC with lymph node metastasis was compared.Results:A total of 112 patients were identified with 120 lymph nodes, among which 98 lymph nodes were confirmed to have metastasis by pathology. The results of the FNA cytology examination revealed 83 positive cases and 37 negative cases. The accuracy, sensitivity, and specificity for diagnosing lateral cervical lymph node metastasis were 80.83%, 80.61%, and 81.82%, respectively. In the FNA-Tg, there were 89 positive cases and 31 negative cases, with accuracy, sensitivity, and specificity for diagnosing lateral cervical lymph node metastasis at 89.17%, 88.78%, and 90.91%, respectively. When FNA and FNA-Tg were used in combination, there were 101 positive cases and 19 negative cases; the accuracy, sensitivity, and specificity for diagnosing lateral cervical lymph node metastasis were 94.17%, 97.96%, and 77.27%, respectively. The combined use of FNA and FNA-Tg demonstrated significantly higher accuracy in diagnosing metastatic lateral cervical lymph nodes in PTC compared to FNA and FNA-Tg alone ( χ2 = 50.64, P < 0.001; χ2 = 64.81, P < 0.001). Conclusions:The combined use of FNA and FNA-Tg demonstrates high accuracy in diagnosing lateral cervical lymph node metastasis in PTC.

Objective To observe the value of CT angiography(CTA)for classifying type of peripheral arteriovenous fistula(AVF)in children.Methods Totally 22 children with peripheral AVF were retrospectively enrolled,the type of AVF was classified with preoperative CTA,and therapeutic planning was developed.Taken digital subtraction angiography(DSA)findings during interventional therapy as gold standards,the efficacy of CTA for classifying type of AVF was analyzed.Results Among 22 cases,DSA detected 3 cases of type Ⅰ,13 cases of type Ⅱa and 6 cases of typeⅡb peripheral AVF,while 3 cases of type Ⅰ,14 cases of type Ⅱa and 5 cases of type Ⅱb peripheral AVF were classified based on CTA.CTA misdiagnosed 1 case of type Ⅱa as type Ⅱb,and 2 cases of type Ⅱb as type Ⅱa peripheral AVF,its accuracy of CTA for classifying type Ⅰ,Ⅱa and Ⅱb peripheral AVF was 100%(3/3),92.31%(12/13)and 66.67%(4/6),respectively.Among 22 cases,13 cases underwent interventional closure,2 cases underwent interventional therapy combined with surgery,while 3 cases did not receive relevant treatment due to drainage vein occlusion.One month after treatments,the symptoms of 19 cases who underwent treatment improved significantly,and no signs of AVF was found with re-examination of ultrasound nor CTA.Conclusion CTA was helpful to classifying type of peripheral AV in children,which could provide references for interventional therapy.

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.

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 construction of fluorinated human serum albumin (F-HSA) nanoparticles loaded with epirubicin (EPI) EPI@F-HSA and its potential in urothelium penetration after bladder perfusion in female C57 mice.Methods:From January 2023 to December 2023, HSA and EPI were selected as raw materials to synthesize albumin nanoparticles loaded with EPI (EPI@HSA) based on the principles of biomineralization. EPI@F-HSA was synthesized through an amide reaction. The molecular descriptor of hydrated particles were measured by dynamic light scattering and potentiometric analyzer, and the release curve of EPI in vitro was plotted at 0.25, 0.5, 1, 2, 4, 8, 12, 24 and 48 h. The inhibitory effect of EPI@HSA and EPI@F-HSA nanoparticles on MB49 tumor cell activity was determined by MTT assay. The fluorescence distribution of EPI in mouse bladder sections after drug infusion was recorded by confocal microscope and the difference of fluorescence density of EPI was examined by Tukey post-hoc test to reflect the urothelium permeability.Results:The average hydrated particle sizes of EPI@HSA and EPI@F-HSA were 28.2 nm and 32.7 nm, respectively, and the polydispersity index (PDI) were 0.102 and 0.154. The cumulative EPI release of EPI@HSA and EPI@F-HSA nanoparticles within 12 h were 60.5% and 58.2% respectively in pH 5.0 buffer solution, and were 32.8% and 27.1% in pH 7.4 buffer solution. The median inhibitory concentrations of EPI@HSA and EPI@F-HSA nanoparticles on MB49 bladder cancer cells were 1.848 μmol/L and 1.650 μmol/L respectively. After perfusion with EPI, EPI@HSA, and EPI@F-HSA, the fluorescence intensities of EPI in the bladder wall were 2.63±0.43, 3.22±0.20 and 8.71±0.70, respectively, and the EPI fluorescence intensity of EPI@F-HSA was significantly higher than that of EPI@HSA ( P<0.01) and free EPI ( P<0.01). Conclusions:The fluorinated albumin nanoparticles had uniform particle size, good stability, significant inhibition of tumor cell activity and osmotic potential in urothelium, which had the potential to improve the anti-tumor efficacy and were expected to become a new drug delivery system targeting bladder cancer.

Objective:To evaluate spinal-pelvic mobility and sagittal spinal-pelvic alignment characteristics in patients with developmental dysplasia of the hip (DDH), and to investigate differences in sagittal spinal-pelvic parameters between patients with DDH and those with osteonecrosis of the femoral head (ONFH).Methods:A total of 55 patients with DDH who underwent primary total hip arthroplasty (THA) at the Affiliated Hospital of Xuzhou Medical University between April 2021 and March 2024 were retrospectively analyzed. The cohort included 8 males and 47 females, with a mean age of 56.16±10.82 years (range: 26-76 years). Among them, 18 patients had bilateral DDH and 37 had unilateral DDH. Fifty-five age- and sex-matched patients with ONFH were selected as the control group. Unilateral DDH cases were classified according to the Hartofilakidis classification: 18 cases of type A, 13 cases of type B, and 6 cases of type C. Lateral spinal-pelvic radiographs were used to measure pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and lumbar lordosis (LL) in both standing and sitting positions. Changes in sagittal spinal-pelvic parameters between standing and sitting positions were analyzed to assess spinal-pelvic mobility. Spinal-pelvic mobility was considered abnormal if △SS was outside the range of 10°-30°. Abnormal mobility was further categorized as stiffness (△SS<10°) or hypermobility (△SS>30°).Results:The PI (52.37°±12.43°), standing PT (12.13°±9.50°), and sitting PT (36.49°±13.43°) of DDH patients were significantly higher than those of ONFH patients (44.88°±11.38°, 7.80°±11.36°, and 28.91°±11.38°, respectively), with statistically significant differences ( P<0.05). Abnormal spinal-pelvic mobility, including both stiffness and hypermobility, was observed in 53% of DDH patients, with stiffness accounting for 20%. These proportions were significantly higher than those in ONFH patients, which were 24% and 6%, respectively ( P<0.05). The prevalence of abnormal spinal-pelvic mobility in Hartofilakidis type C DDH patients was 83%, significantly higher than the 30.8% observed in type B patients (χ 2=4.550, P=0.033). The standing LL (54.37°±11.59°) and sitting LL (28.56°±15.51°) in unilateral DDH patients were significantly greater than those in bilateral DDH patients (46.88°±15.30° and 20.42°±9.77°, respectively), with statistically significant differences ( P< 0.05). Conclusions:Compared with patients with ONFH, those with DDH demonstrate a higher prevalence of abnormal spinal-pelvic mobility, particularly a greater incidence of spinal stiffness. Among DDH subtypes, Hartofilakidis type C patients exhibit a higher proportion of abnormal mobility compared to types A and B. Additionally, patients with unilateral DDH present with greater lumbar lordosis than those with bilateral involvement.