Objective:To conduct a phased summary and analysis of the operation and quality control (QC) of the first human milk bank (HMB) in East China over a ten-year period.Methods:Data on the operation of the HMB at Women's Hospital of Nanjing Medical University, characteristics of donors and recipients, clinical application of donated milk, and operational costs from August 1, 2013, to July 31, 2023, were collected, organized, analyzed, and described. Quality and safety management of the HMB began in 2016, with QC measures implemented. Chi-square tests were used to compare data related to the operation of the HMB, donors, and recipient infants before QC (2013-2015) and after QC (2016-2023). Results:Over the ten-year period since its establishment, the HMB received donor human milk (DHM) from 1 974 donors, totaling 9 390.41 liters. The qualification rate of donors was 86.47% (1 707/1 974), with a qualification rate of DHM of 98.01% (9 203.21/9 390.41) and 21 757 donation instances, with the highest individual donation count reaching 195 times. In the past 10 years, due to the epidemic of the new coronavirus in 2020, the number of milk donors, the amount of DHM and the total number of milk donations decreased significantly, but the amount of DHM per capita and the number of milk donations per capita showed a continuous upward trend. Compared to the period before QC, the qualification rate of donors [96.75% (1 253/1 295) vs. 66.86% (454/679), χ 2=340.33, P<0.001] and the qualification rate of DHM [98.19% (8 366.76/8 521.08) vs. 96.22% (836.45/869.33), χ 2=16.33, P<0.001] both improved after QC. A total of 11 197 recipients received 6 615.38 liters of DHM, with a utilization rate of 71.88% (6 615.38/9 203.21). The current operation mode of the HMB is "voluntary donation, free use". Over ten years, the costs for consumables, testing, labor, energy, and fixed assets amounted to 9.36 million CNY, with an operational cost of 996.32 CNY per liter (9.36 million/9 390.41 L) and approximately 1.00 CNY per milliliter of DHM. Conclusions:The hospital's HMB has been operating stably for ten years, and abundant DHM benefits many newborns. QC measures have effectively increased the qualification rates of both donors and DHM, providing better nutritional support for the treatment of critically ill infants. However, the operational costs of the HMB are relatively high, necessitating the exploration of an operational model suitable for China's national conditions.

Breast milk is an ideal source of nutrition for the growth and development of infants. The study of metabolomics integrates holistic and dynamic technological approaches, which offers practical feasibility for the analysis of small molecular metabolites in breast milk, including their composition, structure, functionality, as well as their relationship with maternal and infant health. This article provides an overview of the origins and development of breast milk metabolomics, influencing factors, and the relationship between breast milk metabolites and the health of the offsprings.

Objective:To investigate the incidence, influencing factors, and clinical characteristics during hospitalization of small for gestational age (SGA) infants among very preterm infants (VPIs) in neonatal intensive care units (NICUs).Methods:This study was a multicenter cohort study. Clinical data of VPIs with gestational age<32 weeks admitted to 19 collaborative units from January 1, 2019 to December 31, 2022, were collected from the Neonatal Perinatal Collaborative Network of Suxinyun (SNPN) and analyzed. General characteristics, perinatal conditions, and clinical manifestations during hospitalization of SGA infants among the VPIs were analyzed using Chi-square test, Mann-Whitney U test, and multivariate logistic regression. Clinical characteristics of symmetric and asymmetric SGA infants with hospital stay >7 d were also analyzed. Results:(1) During the study period, a total of 5 045 VPIs were included, among which there were 346 large for gestational age (LGA) infants, 4 475 appropriate for gestational age (AGA) infants, and 224 SGA infants, with a SGA incidence of 4.4%. The incidence of SGA was significantly higher in VPIs born at 30-31 +6 gestational weeks than in those with gestational age<28 weeks and born at 28-29 +6 weeks [6.1% (145/2 380) vs. 3.0% (25/833) and 3.6% (54/1 486), χ 2=11.77 and 11.32, both P<0.001]. No significant difference in SGA incidence was found between VPIs with gestational age<28 weeks and those born at 28-29 +6 weeks ( χ 2=0.65, P=0.248). (2) Multivariate logistic regression analysis showed that multiple pregnancies, hypertensive disorders of pregnancy (HDP) and assisted reproductive technology (ART) were independent risk factors for the occurrence of SGA in VPIs [ OR values (95% CI): 1.94 (1.43-2.64), 7.06 (5.34-9.33), and 1.59 (1.14-2.23)], and there was a significant gender difference, with the incidence of SGA being significantly lower in males than in females ( OR=0.61, 95% CI: 0.46-0.81). (3) The body temperature of SGA infants on admission was lower than that of AGA infants [36.0 °C (35.5-36.5 °C) vs. 36.0 °C (35.8-36.5 °C), Z=-2.08, P=0.004]. Moreover, the fasting time, the duration of parenteral nutrition, and the length of hospital stay for SGA infants were longer [3 d (1-7 d) vs. 2 d (1-5 d), 24 d (16-34 d) vs. 19 d (13-29 d), and 47 d (37-61 d) vs. 42 d (30-58 d), Z=-4.13,-4.65, and -3.02, all P<0.05]. The incidence of feeding intolerance, hypoglycemia, neonatal parenteral nutrition-associated cholestasis, and extrauterine growth restriction (EUGR), and the rate of treatment withdrawal or death were also higher in SGA infants [69.8% (143/205) vs. 58.9% (2 450/4 157), 17.6% (36/205) vs. 7.0% (292/4 157), 13.7% (28/205) vs. 6.4% (265/4 157), 77.7% (159/205) vs. 55.2% (2 295/4 157), and 7.8% (16/205) vs. 3.9% (162/4 157), χ 2=9.49, 31.19, 16.54, 44.40, and 7.62, all P<0.05]. Among SGA infants with hospital stay >7 d, there were 111 cases (54.1%) of symmetric SGA and 94 cases (45.9%) of asymmetric SGA. Compared with symmetric SGA infants, asymmetric SGA infants had shorter body length [34 cm (32-36 cm) vs. 38 cm (36-40 cm), Z=-8.49] and lower Apgar score at 1 min [7 points (5-8 points) vs. 8 points (5-8 points), Z=-3.05]. Besides, the proportion of multiple pregnancies and the incidence of postnatal hypoglycemia were higher in asymmetric SGA cases [38.3% (36/94) vs. 21.6% (24/111), 24.5% (23/94) vs. 10.8% (12/111), χ 2=6.84 and 6.71, both P<0.05], while the incidence of feeding intolerance and EUGR during hospitalization was lower [61.7% (58/94) vs. 76.6% (85/111), 58.5% (55/94) vs. 79.3% (88/111), χ2=5.34 and 10.41, both P<0.05]. Conclusions:Multiple pregnancies, HDP, and ART can increase the risk of SGA in VPIs. SGA infants may have increased risks of parenteral nutrition-related problems and EUGR during hospitalization. Symmetric SGA infants are more likely to develop EUGR.

Objective:To investigate the risk factors of initial non-invasive ventilation(NIV) failure and its association with adverse outcomes in very low birth weight infants (VLBWI).Methods:A retrospective cohort study was conducted, collecting clinical data of 2 102 VLBWI who received NIV within 30 minutes after birth, admitted to 18 NICU of Suxinyun Neonatal Perinatal Collaboration Network (SNPN) from January 1 st, 2019 to December 31 st, 2022. According to the outcome of NIV within the first 72 hours, the study cohort was divided into success group and failure group. Univariate analysis and multivariate Logistic regression analysis were performed to identify risk factors for NIV failure and its association with adverse outcome. Results:A total of 2 102 VLBWI were included, consisting of 1 078 males (51.3%). The gestational age was 29 (28, 31) weeks, and the birth weight was 1 250 (1 090, 1 380) g. The initial NIV failure rate was 15.3%(321/2 102). Multivariate Logistic regression analysis showed that smaller gestational age ( OR=0.67, 95% CI 0.61-0.74, P<0.001), maternal hypertensive disorders during pregnancy ( OR=10.31, 95% CI 7.48-14.21, P<0.001), Apgar score at the first minute ≤7 ( OR=1.40, 95% CI 1.01-1.93, P=0.042), grade 3-4 respiratory distress syndrome (RDS)( OR=2.85, 95% CI 1.69-4.81, P<0.001), ≥2 times pulmonary surfactant (PS) treatment ( OR=3.78, 95% CI 2.09-6.83, P<0.001), fraction of inspired oxygen (FiO 2)>0.30 ( OR=2.21, 95% CI 1.64-2.98, P<0.001) were all independent risk factors for initial NIV failure. The failure group had higher risks of mortality ( OR=10.19, 95% CI 6.50-15.97, P<0.001), pneumothorax ( OR=4.33, 95% CI 1.59-11.79, P=0.004), neonatal pulmonary hemorrhage ( OR=8.48, 95% CI 4.08-17.64, P<0.001), moderate to severe bronchopulmonary dysplasia (BPD)( OR=1.75, 95% CI 1.19-2.56, P=0.004), and intraventricular hemorrhage (IVH) ≥grade Ⅲ ( OR=2.18, 95% CI 1.27-3.73, P=0.004) compared to the success group. Conclusions:Small gestational age, maternal hyertensive disorders during pregnancy, Apgar score at the first minute ≤7, grade 3-4 RDS, PS treatment ≥2 times and FiO 2 >0.30 are risk factors for initial NIV failure in VLBWI. Initial NIV failure is associated with increased risk of mortality, pneumothorax, pulmonary hemorrhage, moderate to severe BPD, and IVH ≥grade Ⅲ.

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.