Stroke-associated pneumonia (SAP) is a common complication after acute stroke and worsens clinical outcomes. We developed and externally validated SENTRY, an early prediction model using routine admission variables and ultra-early chest computed tomography (CT) findings from eight stroke centers. The final model included age, dysphagia, NIHSS (National Institutes of Health Stroke Scale) score, neutrophil-to-lymphocyte ratio, and ultra-early chest CT abnormalities. Compared with a base model, adding chest CT findings improved discrimination (area under the curve [AUC]: 0.811 vs. 0.886) and lowered the Brier score from 0.146 to 0.122. Across validation cohorts, SENTRY showed higher discrimination than established scores (A2DS2 and ISAN), and decision curve analysis showed greater net benefit across clinically relevant thresholds. SENTRY stratified patients into low-, medium-, and high-risk groups, with stepwise increases in pneumonia incidence. We applied target trial emulation to further illustrate its potential use for risk-enriched trial. A web calculator implements both base and chest CT-inclusive versions of SENTRY to support early risk estimation and risk-stratified workflows.

Purpose: We aimed to investigate alterations in the skin microbiome following treatment and discontinuation of dupilumab in children with atopic dermatitis (AD). Methods: In all, 24 pediatric AD patients and 10 pediatric health volunteers (HVs) were included. AD patients were treated with dupilumab for 16 weeks and following by a 12-week discontinuation. Cutaneous samples were collected from HVs, and AD patients at baseline and during dupilumab application period (Week 2, Week 4, Week 8, Week 12, and Week 16) and discontinuation period (Week 22 and Week 28) to conduct sequencing targeting the 16s rRNA V3-V4 regions. Clinical severity was assessed using the Eczema Area and Severity Index (EASI), Individual Signs Score (ISS), Children's Dermatology Life Quality Index scores (CDLQI), Patient Oriented Eczema Measure (POEM), and peak pruritus Numerical Rating Scale (NRS itch). Results: Dupilumab treatment significantly improved AD characteristics, with reductions in EASI, ISS, CDLQI, POEM, and NRS itch scores (all P < 0.01). Concurrently, 16s rRNA sequencing indicated decline in Staphylococcus aureus abundance and increase in microbial diversity. These changes began to reverse upon treatment discontinuation, coinciding with a trend toward worsening EASI scores. Moreover, a dupilumab-responsive reduction in other bacterial genera such as Aggregatibacter, and Megasphaera were observed; and these alterations could be reversed after treatment cessation. Conclusion: We provided a dynamical pattern of skin bacterial community during and after dupilumab therapy in pediatric AD patients. Our findings suggest that the therapeutic action of dupilumab may extend to modulating a wider range of bacteria than previously recognized. The roles of our identified candidate microbial taxa require further investigation in larger and functional studies.

Increased antimicrobial resistance requires effective ways to overcome the global challenge of bacterial infections, including methicillin-resistant Staphylococcus aureus (MRSA). From the emergence of MRSA to its continued evolution, it is important to explore this pathogen from fresh perspectives and develop corresponding coping strategies to counter its growing threat. New coping strategies are continuously emerging, including but not limited to enhancing penetration capabilities or targeting their virulence. This review summarizes the epidemiological characteristics, drug resistance mechanisms, and therapeutic strategies of MRSA that have emerged over the past fifteen years. The focus of this paper is to explore the promising applications and current limitations of novel MRSA control strategies. This review serves as a key resource for treating MRSA infections and discussing novel strategies to overcome bacterial drug resistance.

To summarize the clinical characteristics and prognosis of severe infant botulism and evaluate the therapeutic effect of botulinum antitoxin in the pediatric intensive care unit (PICU).

This study aimed to evaluate the seroprevalence of Bordetella pertussis and persistence of antibodies following vaccination. We recruited 6060 healthy subjects from five provinces of China during 2017-2018. Serum IgG antibodies against pertussis toxin (anti-PT IgG) and filamentous hemagglutinin (anti-FHA IgG), and serum IgA antibodies against pertussis toxin (anti-PT IgA) were measured by ELISA. Geometric mean concentration (GMC), seropositivity rate, and recent infection rate were calculated. Among 0-6 years-olds, the anti-PT IgG, anti-PT IgA, and anti-FHA IgG GMCs were 6.4 IU/ml (95% CI 6.1-6.8), 2.8 IU/ml (95% CI 2.7-2.8), and 13.3 IU/ml (95% CI 12.4-14.2), respectively. The anti-PT IgG GMC increased in accordance with the primary vaccination series (4-6 months) and the toddler booster (18-24 months), but declined thereafter through to age 5 years [4.7 IU/ml (95% CI 4.2-5.4)]. The seropositivity rate of pertussis in >6 year-olds was 9.0% (95% CI 8.1-9.9) and the recent infection rate was 3.3% (95% CI, 2.7-3.8). Recent infection rate began to increase from 6 years of age, with peaks at 9, 20, 40, and >= 60 years of age. The anti-PT IgG GMCs of children aged 0-6 years who were vaccinated with DTaP, DTaP-IPV//PRP similar to T, and DTaP-Hib were 5.9 IU/ml (95% CI 5.6-6.3), 20.7 IU/ml (95% CI 15.6-27.8), and 11.7 IU/ml (95% CI 7.5-18.1) (p < .001), respectively (p < .001). Pertussis vaccination improves anti-PT IgG levels, however these wane soon after vaccination. Sero-estimated recent infection rates appear to increase from school age into adolescence and adulthood. Pertussis vaccine boosters should be considered in these age groups.

Antimicrobial resistance has been an increasingly serious threat to global public health. The contribution of non-antibiotic pharmaceuticals to the development of antibiotic resistance has been overlooked. Our study found that the anti-inflammatory drug phenylbutazone could protect P. aeruginosa against antibiotic mediated killing by binding to the efflux pump regulator MexR. In this study, antibiotic activity against P. aeruginosa alone or in combination with phenylbutazone was evaluated in vitro and in vivo. Resazurin accumulation assay, transcriptomic sequencing, and PISA assay were conducted to explore the underlying mechanism for the reduced antibiotic susceptibility caused by phenylbutazone. Then EMSA, ITC, molecular dynamic simulations, and amino acid substitutions were used to investigate the interactions between phenylbutazone and MexR. We found that phenylbutazone could reduce the susceptibility of P. aeruginosa to multiple antibiotics, including parts of β-lactams, fluoroquinolones, tetracyclines, and macrolides. Phenylbutazone could directly bind to MexR, then promote MexR dissociating from the mexA-mexR intergenic region and de-repress the expression of MexAB-OprM efflux pump. The overexpressed MexAB-OprM pump resulted in the reduced antibiotic susceptibility. And the His41 and Arg21 residues of MexR were involved in the phenylbutazone-MexR interaction. We hope this study would imply the potential risk of antibiotic resistance caused by non-antibiotic pharmaceuticals.

Objective:To comprehensively examine the molecular epidemiological characteristics of human rhinovirus (HRV) in Beijing. Methods:A total of 7,151 children and adults with acute respiratory tract infections (ARTIs) were recruited from 35 sentinel hospitals in Beijing between 2018 and 2022. Their respiratory samples were obtained, and epidemiological and clinical data were collected. Nucleic acid testing for 11 respiratory pathogens, including HRV, was performed on the specimens. We sequenced VP4/VP2 or 5'UTR of HRV isolates to identify their genotypes using phylogenetic analyses. Results:HRV was detected in 462 (6.5%) cases. A total of 105 HRV genotypes were successfully identified in 359 (77.7%) specimens, comprising 247 (68.8%) with HRV-A, 42 (11.7%) with HRV-B, and 70 (19.5%) with HRV-C. No predominant genotype was observed. HRV was prevalent year-round with two weak peaks in spring and autumn. HRV detection declined gradually between 2018 and 2022, with seven genotypes disappearing and five genotypes emerging. HRV detection rate decreased by age without resurge among old people. HRV-C was more common among children aged less than 5 years with severe community-acquired pneumonia compared to HRV-A and HRV-B. Adults infected with HRV-B had higher rates of hospitalization, intensive care unit admission, and complications than those infected with HRV-A and HRV-C. Conclusion:HRV epidemics in Beijing were highly dispersed in genotypes, which probably resulted in a high prevalence of HRV infection, attenuated its seasonality, and made it more difficult to establish effective population immunity.

PURPOSE:Bone and joint tuberculosis (BJTB) is a distinct variant of tuberculosis in which clinical diagnosis often leads to relative misdiagnosis and missed diagnoses. This study aimed to evaluate the diagnostic accuracy of the targeted nanopore sequencing (TNPseq) assay for BJTB patients in China. METHOD:The study enrolled a cohort of 163 patients with suspected BJTB. Diagnostic testing was performed using the TNPseq assay on samples including punctured tissue, pus, and blood. The diagnostic accuracy of the TNPseq assay was then compared with that of the T-SPOT and Xpert MTB/RIF assays. RESULT:TNPseq exhibited superior performance in terms of accuracy, demonstrating a sensitivity of 76.3% (95% CI: 71.0-81.6%) and a specificity of 98.8% (95% CI: 93.5-100%) in clinical diagnosis. When evaluated against a composite reference standard, TNPseq demonstrated a sensitivity of 74.4% (95% CI: 69.3-79.5%) and a specificity of 98.8% (95% CI: 93.7-100%). These results exceed the performance of both the T-SPOT and Xpert MTB/RIF tests. Notably, TNPseq demonstrated high specificity and accuracy in puncture specimens, with a sensitivity of 75.0% (95% CI: 70.2-79.8%) and a specificity of 98.3% (95% CI: 92.7-100%), as well as in pus samples, with a sensitivity of 83.3% (95% CI: 78.6-88.1%) and a specificity of 100% (95% CI: 100-100%). Additionally, TNPseq facilitated the detection of mixed infection scenarios, identifying 20 cases of bacterial-fungal co-infection, 17 cases of bacterial-viral co-infection, and two cases of simultaneous bacterial-fungal-viral co-infection. CONCLUSION:TNPseq demonstrated great potential in the diagnosis of BJTB due to its high sensitivity and specificity. The ability of TNPseq to diagnose pathogens and detect drug resistance genes can also guide subsequent treatment. Expanding the application scenarios and scope of TNPseq will enable it to benefit more clinical treatments.

Background: Skin and Soft Tissue Infections (SSTIs) Surveillance Network of S. aureus In Pediatrics in China was established in 2009 to routinely report epidemiological changes. We aimed to monitor the present antibiotic sensitivity and molecular characteristics of S. aureus and methicillin-resistant S. aureus (MRSA) from SSTIs in children nationwide and track the changes over the past decade. Methods: Patients diagnosed with SSTIs from the dermatology departments of 22 tertiary pediatric hospitals in seven geographical regions of China were recruited continuously from May 2019 to August 2021. S. aureus was isolated, and its sensitivity to 15 antimicrobials was evaluated using the broth microdilution method. The molecular characteristics of the MRSA isolates were determined through multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. The presence of the Panton-Valentine leukocidin gene (pvl) was determined. Results: The detection rate of S. aureus was 62.57% (1379/2204), among which MRSA accounted for 14.79% (204/1379), significantly higher than the result in previous study in 2009-2011 (2.58%, 44/1075). Compared with previous study, the sensitivity to cephalosporins and fusidic acid decreased to varying degrees, while that to chloramphenicol, ciprofloxacin, clindamycin, erythromycin, gentamicin, penicillin, and tetracycline increased significantly. The sensitivity to mupirocin, trimethoprim/sulfamethoxazole (TRISUL), and rifampicin still maintained at a high level (97.90%, 99.35% and 96.66% respectively). The leading multidrug resistance pattern of MRSA and methicillin-sensitive S. aureus (MSSA) were erythromycin-clindamycin-tetracycline (55.84%; 43/77) and erythromycin-clindamycin-chloramphenicol (27.85%, 44/158) respectively. 12 high-level mupirocin-resistant strains were detected, and notable differences in geographical distribution and seasonal variation were observed. The main types of MRSA were ST121 (46.08%, 94/204), followed by ST59 (19.61%, 40/204). SCCmec V (65.69%, 134/204) and SCCmec IV (31.86%, 65/204) were dominant epidemic types. ST121-V, ST59-IV, and ST22-V were the most prevalent clones nationwide. The detection rate of pvl had increased markedly from 9.09% (4/44) in 2009-2011 to 22.55% (46/204) in 2019-2021 (P<0.05). Conclusion: The antibiotic sensitivity and molecular characteristics of S. aureus from pediatric SSTIs has changed significantly over the past decade. To standardize medical care, provide timely and reasonable clinical treatment, and effectively manage infection control, Chinese pediatric SSTIs guidelines are urgently needed.

IntroductionBordetella pertussis and respiratory syncytial virus (RSV) are important pathogens causing cough in neonates. Few studies have investigated the differences in the effects of these two specific infections on respiratory flora. The aim of this study was to explore whether infections with Bordetella pertussis and RSV have different effects on respiratory floral composition in neonates.MethodsNasopharyngeal respiratory flora was assessed by 16S ribosomal RNA amplification and V3–V4 region sequencing. Shannon and Simpson indices were calculated to determine the α diversity and principal coordinate analysis was performed to determine the β diversity.ResultsIn total, 111 hospitalized neonates were divided into the pertussis (n = 29), RSV (n = 57), and control groups (n = 25) according to the pathogens detected. The relative abundance of Bordetella was significantly higher in the pertussis group (median: 19.18%, interquartile range: 72.57%). In contrast, this species was not detected in the other two groups. In the RSV group, the relative abundance of Streptococcus (median: 77.15%, interquartile range: 45.84%) was significantly higher than those in the pertussis and control groups (both P < 0.001). The α diversity of the RSV group was significantly lower than that of the control group (P < 0.001). Moreover, no statistically significant differences in the Shannon and Simpson indices were observed between the pertussis and control groups (P = 0.101 and P = 0.202, respectively). Principal coordinate analysis revealed a large overlap between the pertussis and control groups and a significant distance between the RSV and control groups without any overlap.DiscussionThus, the effects of infections with the two species, B. pertussis and RSV, impacted the diversity of nasopharyngeal flora differently. The principles underlying the difference in the effects of different pathogens on microbial flora require further investigation.

Background Gait speed and grip strength are simple markers of physical capability, which are associated with adverse outcomes in the elderly. However, there are few studies on the prediction of adverse outcomes in this population by the combination of the two markers. Objective To investigate the associations of gait speed and grip strength with adverse outcomes in geriatric inpatients. Methods A cohort design was used in this study. From August 2015 to December 2018, eligible geriatric inpatients aged≥65 years were recruited from Department of Geriatrics, Fuxing Hospital, Capital Medical University. We measured the gait speed and grip strength with 6-meter walking test and dynamometer, respectively. By the gait speed, the patients were divided into tertiles (T1 group: ≤ 0.6 m/s, T2 group: >0.6-0.8 m/s, T3 group: >0.8 m/s). By the grip strength, they were divided into L1, L2 and L3 tertiles (L1 group: ≤ 21.6 kg for males, ≤ 14.6 kg for females; L2 group: > 21.6 kg but ≤ 28.2 kg for males, >14.6 kg but ≤ 19.4 kg for females; L3 group: >28.2 kg for males, >19.4 kg for females). Follow-up was conducted by telephone once every three months within one year after discharge and once half a year after this until December 31, 2019. All-cause mortality and falls were recorded. Survival curves were constructed by the Kaplan-Meier method. Cox regression analysis was used to investigate the association of gait speed, grip strength, or their combination with all-cause mortality and falls. ROC curves for comparing the ability of the two makers or their combination on predicting all-cause mortality and falls. Results Among the 685 patients, 29 (4.2%) were lost to follow-up, and the other 656 cases who finished the follow-up with complete data were included for analysis. During the follow-up period, 130 patients (19.8%) died from all causes and 147 patients (22.4%) experienced falls. There were 222, 225 and 209 patients in the low, moderate and high tertiles of gait speed (T1, T2 and T3 groups), and 215, 229 and 212 patients in the low, moderate and high tertiles of grip strength (L1, L2 and L3 groups), respectively. Log-rank test showed that the cumulative survival curves of all-cause mortality and falls differed significantly among T1, T2 and T3 groups (P<0.01). The same results were obtained in L1, L2 and L3 groups (P≤0.01). Cox regression analysis with adjustment for potential confounders showed that compared to patients in high tertiles of both gait speed and grip strength, the risk of all-cause mortality significantly increased in those both in low gait speed and low or moderate tertiles grip strength〔HR=3.29, 95%CI (1.13, 9.55) ; HR=3.09, 95%CI (1.08, 8.85) ; P<0.05〕, and the risk of fall significantly increased in those in low tertiles of both gait speed and grip strength 〔HR=1.92, 95%CI (1.13, 4.27), P<0.05〕. The prediction probability of the joint diagnostic model of gait speed and grip strength was estimated by Logistic regression analysis, and the AUC of the combination of them for predicting all-cause mortality and falls was 0.756 〔95%CI (0.710, 0.801) 〕, and 0.700〔95%CI (0.659, 0.741) 〕, respectively. Conclusion In geriatric inpatients, the combination of gait speed and grip strength had higher predictive value for all-cause mortality and falls, which is helpful to optimize the health management.

Objective:To evaluate the antibacterial activity of pediatric Faropenem sodium against common pathogens isolated from children′s respiratory tract in vitro, and to provide reference for its clinical research and application. Methods:Retrospective analysis.The minimum inhibitory concentration (MIC) of Faropenem sodium, Merope-nem, Imipenem and other antibiotics was determined by the agar dilution method.A total of 156 strains of Streptococcus pneumoniae [including 32 strains of Penicillin-susceptible Streptococcus pneumoniae (PSSP), 28 strains of Penicillin-intermediate Streptococcus pneumoniae (PISP) and 96 strains of Penicillin-resistant Streptococcus pneumoniae (PRSP)], 98 strains of Haemophilus influenza, 173 strains of Klebsiella pneumoniae, and 55 strains of Moraxella catarrhali clinical isolates were used.MIC 50, MIC 90 and the accumulative inhibition of the bacteria were investigated. Results:The MIC of Faropenem sodium against all the Streptococcus pneumoniae strains ranged from 0.010-2.000 mg/L.There was no difference in the MIC distribution of Faropenem sodium against PSSP, PISP and PRSP, and the MIC 90 value was all 1.000 mg/L.Faropenem sodium inhibited all the Haemophilus influenza strains at concentrations ranging from 0.030-8.000 mg/L.There was no difference in the MIC distribution of Faropenem sodium against Haemophilus influenza with or without β-lactamase and Ampicillin resistance.The MIC 90 value was all 4.000 mg/L.Ho-wever, the MIC of Faropenem sodium against Klebsiella pneumoniae ranged from 0.250 to above 32.000 mg/L, and both MIC 50 and MIC 90 were greater than 32.000 mg/L.Faropenem sodium inhibited all the Moraxella catarrhalis strains at concentrations ranging from 0.030-2.000 mg/L, with MIC 50 being 0.500 mg/L and MIC 90 being 1.000 mg/L. Conclusions:Antimicrobial susceptibility testing results in vitro demonstrate that pediatric Faropenem sodium has satisfactory antibacterial activities against Streptococcus pneumoniae, Haemophilus influenza, and Moraxella catarrhalis, but comparatively weak antibacterial activities against Klebsiella pneumoniae.

子宫腺肌病是一种雌激素依赖性疾病,常见于育龄期女性,近年来发病率逐年升高并呈年轻化趋势;其性质一般为良性,但具有与恶性肿瘤类似的侵袭与增殖过程.病理组织特点为病灶周围存在大量致密的纤维组织及胶原沉积,提示疾病发生发展过程中存在类似于纤维化疾病的损伤修复过程.目前涉及子宫腺肌病纤维化发病的机制较为复杂,包括上皮-间充质转化、内质网应激、氧化应激等,各分子机制间相互作用,共同促进子宫腺肌病的发生与进展.

目的 探究羊膜腔灌注对足月孤立羊水过少产妇分娩结局的影响.方法 本研究为回顾性研究,选择2017-01至2019-01北京妇产医院产科93例足月孤立羊水过少经腹羊膜腔灌注后引产患者作为灌注组,取同期135例足月孤立羊水过少产妇未接受羊膜腔灌注而直接引产为对照组,比较两组分娩结局.结果 灌注组与对照组一般情况如年龄、孕次、产次、分娩孕周及羊水指数等方面比较,差异无统计学意义(均P>0.05).灌注组中14例中转剖宫产手术,剖宫产率15.0％;对照组中40例中转剖宫产,剖宫产率29.6％,灌注组剖宫产率低于对照组,差异有统计学意义(P<0.01).灌注组与对照组比较,产后出血量[(352.58±163.05)ml vs.(353.78±99.09)ml]、胎儿窘迫发生率(25.8％vs.34.1％)、羊水Ⅲ度粪染发生率(19.4％vs.24.4％)、新生儿窒息率(1.1％vs.4.4％)均无统计学差异.结论 羊膜腔灌注可降低足月羊水过少产妇剖宫产率,不增加并发症发生率,提高产科质量.

目的 探讨非急性冠状动脉综合征(ACS)、无急慢性心力衰竭的老年住院患者高敏肌钙蛋白T(hs-cTnT)和N末端B型钠尿肽前体(NT-proBNP)与衰弱的关系.方法 入选住院患者772例,根据Fried表型衰弱量表评估为无衰弱组309例、衰弱前期组199例,衰弱组264例.检测各组hs-cTnT及NT-proBNP水平.结果 与无衰弱组比较,衰弱前期组和衰弱组血红蛋白、白蛋白水平明显降低,hs-cTnT及NT-proBNP水平明显升高,衰弱组左心室舒张末期内径(LVEDD)和LVEF明显降低(P＜0.05,P＜0.01).衰弱组血红蛋白、白蛋白、LVEDD及LVEF明显低于衰弱前期组,hs-cTnT、NT-proBNP水平明显高于衰弱前期组(P＜0.01).校正合并慢性疾病后logistic回归分析显示,hs-cTnT、NT-proBNP对数转换(lgNT-proBNP)为衰弱前期和衰弱的独立危险因素(P＜0.05,P＜0.01),校正实验室及超声心动图检查指标等混杂因素后,hs-cTnT仍为衰弱前期和衰弱的独立危险因素(P＜0.01),而lgNT-proBNP与衰弱及衰弱前期无相关性(P＞0.05).hs-cTnT预测衰弱的ROC曲线下面积(AUC)为0.676 (95 ％CI:0.636～0.717),NT-proBNP预测衰弱的AUC为0.669(95％CI:0.629～0.708),hs-cTnT预测衰弱的AUC稍高于NT-proBNP(P＞0.05).结论 无ACS及无急慢性心力衰竭的老年住院衰弱患者hs-cTnT和NT-proBNP水平高,hs-cTnT与衰弱、衰弱前期独立相关,hs-cTnT预测衰弱的AUC稍高于NT-proBNP.

目的 本研究旨在探讨妊娠期高血压患者血清脂联素(adiponectin,APN)水平与肾功能及妊娠结局的相关性,为妊娠期高血压肾损伤的诊断及预测妊娠结局寻找潜在的生物学标志.方法 选取2017年1月至2019年12月首都医科大学附属北京妇产医院接诊的30例妊娠期高血压患者作为研究组,另选取同期来院产检的30例正常孕妇作为对照组.比较分析两组孕妇血清APN、24h尿蛋白、血肌酐、血尿素氮、血尿酸水平以及不良妊娠结局发生率.结果 与对照组相比,研究组孕妇血清APN水平显著降低,24h尿蛋白、血肌酐、血尿素氮以及血尿酸的水平明显上升,差异有显著性(P<0.05).研究组孕妇的早产、新生儿窒息以及新生儿呼吸窘迫综合征的发生率高于对照组.不良妊娠结局的总体发生率明显高于对照组,差异有显著性(P<0.05).结论 妊娠期高血压患者血清APN水平降低与肾功能损伤及不良妊娠结局的发生率有关,孕妇血清APN水平、肾功能指标可以对妊娠结局起到很好的预测作用.

Background: Our study aims to explore the epidemiological features of children with bacterial culture-confirmed pertussis visiting Beijing Children's Hospital, China. Methods: From 2014 through 2019, patients with suspected pertussis coming from mainland China provided nasopharyngeal swabs and bacterial culture that was subsequently cultivated. Results: During the study period, 6956 children with suspected pertussis from 30 different administrative provinces of mainland China were investigated, of which 1494 cases (21.5%) had positive B. pertussis culture. The number of pertussis cases increased year-on-year, from 122 in 2014 to 279 in 2019. Of the confirmed cases, 38.2% and 26.8% were identified in the summer and autumn, respectively. The age distribution of children with pertussis showed that 77.2% were <12 months old, including 56.0% B. parapertussis isolates and one B. bronchiseptica isolates were collected in the present samples. Conclusions: The present culture-confirmed cases reveal the severe epidemic situation of pertussis spreading over the whole country and mainly affecting the infants. It is necessary to set up hospital-based surveillance with reliable laboratory methods to promote clinical awareness and to monitor the disease.

背景 金黄色葡萄球菌(SA)在鼻腔和体表的定植可增加新生儿SA感染的风险,了解住院新生儿的SA定植状况、菌株分子型及耐药性有助于制定合理的治疗方案.目的 探讨NICU患儿入院时体表的SA定植、菌株分子特征及耐药性.设计横断面研究.方法 纳入2020年8月1日至2021年1月31日入住首都医科大学附属北京儿童医院NICU时入院日龄≤28 d且胎龄≥28周的新生儿,收集临床信息.并对入院后12 h内体表部位采集的拭子进行细菌培养和菌落计数,采用Staphytect Plus试剂盒及PCR扩增nuc基因进行SA菌株鉴定,并分别进行抗生素耐药性检测.主要结局指标NICU住院新生儿体表定植的SA分子特征及耐药性.结果 共纳入766例NICU住院新生儿,其中257例(33.6％)存在≥1个部位的SA定植,单部位、2个部位、≥3个部位SA定植组分别为135例(52.5％)、65例(25.2％)和57例(22.3％),各组间的临床特征(男婴、入院日龄、剖宫产、入院前纯母乳喂养、入院前应用抗生素、入院时气管插管常频机械通气、住院天数)、菌株分型(MRSA、MSSA)、sarA基因状态差异均无统计学意义,PVL阳性差异有统计学意义.≥2个部位定植组与1个部位定植组比较,PVL阳性[39(32.0％)vs 23(17.0％),P=0.005]和sarA阳性[83(68.0％)vs 56(41.5％),P<0.01]差异有统计学意义.鼻前庭、脐根部、腋下和腹股沟分别培养出176株、124株、72株和76株,MSSA占比分别为82.4％、77.4％、80.6％和80.3％,各部位SA菌株的MRSA和MSSA占比差异均无统计学意义.MSSA菌株最常见的克隆型为ST398-t309型,MRSA菌株最常见的克隆型为ST59-SCCmecIV-t437.PVL、sarA和PVL+sarA基因检测阳性株,MRSA和MSSA阳性率差异均无统计学意义.所有的288株SA均对莫匹罗星、利奈唑胺及万古霉素敏感;15株美罗培南不敏感株,其中MRSA 14株(1株耐药,13株中介),MSSA 1株(中介);耐药率从高到低依次为青霉素、红霉素、头孢曲松和苯唑西林.结论 NICU相对病情稳定的新生儿鼻腔和体表皮肤SA定植率为33.6％.≥2个部位定植与1个部位定植相比,PVL和sarA阳性更高.MSSA菌株最常见的克隆型为ST398-t309,MRSA菌株最常见的克隆型为ST59-SCCmecIV-t437.本次研究中所有定植的SA菌株均对莫匹罗星、利奈唑胺及万古霉素敏感,有对美罗培南耐药MRSA分子型菌株检出.