This study aimed to investigate the impact of outer membrane proteins 35 (OmpK35) and 36 on the virulence of Klebsiella pneumoniae and the corresponding mechanisms. Serotype K1 strain NTUH-K2044 was utilized to create single-deletion mutants (ΔompK35 and ΔompK36) and a double-deletion mutant (ΔompK35/36), alongside their complementation variants. Multiple analyses were performed, including capsule staining, transmission electron microscopy, serum resistance assays, phagocytosis tests, and infection models using mice and Galleria mellonella. The mutants retained hypercapsules similar to NTUH-K2044, but looser capsule structures revealed by transmission electron microscopy. All mutants exhibited decreased virulence, with median lethal doses under 5 × 10⁴ colony forming units in mice. Specifically, only ΔompK35/36 showed reduced serum resistance compared to the wild strain, similar for the anti- phagocytosis capabilities. Additionally, ΔompK35 induced liver inflammation, whereas ΔompK36 and ΔompK35/36 exerted milder effects. Despite these differences, all mutants displayed normal growth rates and upregulated expression of gnd and wcaJ, crucial for capsular polysaccharide (CPS) biosynthesis. The hypercapsule, composed mainly of CPS, plays a crucial role in the hypervirulence of K. pneumoniae. OmpK35/36 may modulate the virulence of K. pneumoniae by regulating CPS export.

The clinical strain of Pseudomonas aeruginosa XM8 harbored multiple RND-type antibiotic efflux pump genes and a novel integron In4881 on its plasmid pXM8-2, rendering it resistant to nearly all conventional antibiotics except colistin. The resistance was primarily attributed to the inactivation of the oprD gene and overexpression of several efflux pump genes, including mexAB-oprM, mexCD-oprJ, oprN-mexFE, and mexXY. In this study, the XM8 strain was comprehensively characterized using various methods. Antimicrobial susceptibility testing was performed using the BioMerieux VITEK2 system and manual double dilution methods. Gene expression levels of efflux pump-related genes were analyzed via quantitative real-time PCR. The bacterial chromosome and plasmid were sequenced using both Illumina and Nanopore platforms, and bioinformatics tools were employed to analyze mobile genetic elements associated with antibiotic resistance. The pXM8-2 plasmid containsed multiple mobile genetic elements, including integrons (In4881, In334, In413) and transposons (Tn3, TnAs1, TnAs3). Notably, In4881 was reported for the first time in this study. The presence of these elements highlights the potential for horizontal gene transfer and further spread of antibiotic resistance. Given the strong resistance profile of the XM8 strain, effective measures should be implemented to prevent the dissemination and prevalence of such multidrug-resistant bacteria.

OBJECTIVES:In this study, we discovered blaKPC-90 in ceftazidime-avibactam resistant clinical isolates of K. pneumoniae from a patient with multiple comorbidities and investigated the resistance & transfer mechanism of blaKPC-90. METHODS:K. pneumoniae strains carrying blaKPC-2 and blaKPC-90 were isolated from the patient. Antimicrobial susceptibility tests and whole genome sequencing were performed to investigate the phenotype & genotype of strains. Conjugation assays, cloning experiment, kinetic parameters measuring, outer membrane protein SDS-PAGE and qRT-PCR were performed to explore the spread and antimicrobial resistance mechanisms. RESULTS:KPC-90 isolates had an insertion of two amino acids (Thr180_Ser181 ins Tyr Thr) compared to the wildtype KPC-2. Antimicrobial susceptibility testing of isolates with KPC-90 vs. KPC-2 showed ceftazidime-avibactam MICs of >128 vs. 1-2 mg/L, meropenem-vaborbactam MICs of 4 vs. 1 mg/L, meropenem MICs of 4-8 vs. >128 mg/L and imipenem MICs of 0.5-1 vs. 64 mg/L. Analysis of kinetic parameters of KPC-90 compared to KPC-2 showed decreased hydrolysis of carbapenems and increased IC50 of avibactam. Genetic characterization of the plasmid revealed that IS26 could mediate the intramolecular inversion, translocation and truncation of the resistance determinant region. CONCLUSION:We have described the case of a patient infected with blaKPC-90-carrying K. pneumoniae strains and investigated the mechanism of resistance to carbapenems and ceftazidime-avibactam associated with blaKPC-2 and its variants. We have also focused on the functional diversity of IS26 in relation to antimicrobial resistance. In the future, it is crucial to pay more attention to the evolution and horizontal transmission of blaKPC.

ABSTRACT To illustrate the genomic and drug resistance traits of the Klebsiella pneumoniae Kpn_XM9, which harbors a transposon (Tn) As1 and was barely susceptible to ceftazidime–avibactam (CZA). Whole-genome sequencing, gene deletion, antimicrobial susceptibility, and conjugation tests were carried out to illustrate the traits of Kpn_XM9. As confirmed by whole-genome sequencing, the Kpn_XM9 harbored a 5,523,536 bp chromosome and five plasmids with lengths being 128,129, 196,512, 84,812, 43,695, and 5,596 bp, respectively. Plasmid p1_Kpn_XM9 (128,219 bp) contained four resistance genes, bla CTX-M-65 , bla TEM-1B , rmt B, and two copies of bla KPC-2 . Genes bla KPC-2 were bracketed by ISKpn17 and ISKpn16 within a new composite Tn3-like TnAs1. The two tandem repeats, positioned opposite each other, were spaced 93,447 bp apart in p1_Kpn_XM9. Kpn_XM9 belonged to K64 and sequence type (ST) 11. The Kpn_XM9 was resistant to amikacin, aztreonam, ticarcillin/clavulanic acid, piperacillin/tazobactam, ceftazidime, cefepime, imipenem, meropenem, tobramycin, ciprofloxacin, levofloxacin, doxycycline, minocycline, tigecycline, colistin, and trimethoprim/sulfamethoxazole; it was barely susceptible to CZA with a minimum inhibitory concentration of 8/4 µg/mL, which declined to 2/4 µg/mL after a 18,555 bp nucleotide was knocked out and one copy of bla KPC-2 was sustained on p1_Kpn_XM9. Kpn_XM9 had virulence genes encoding Types 1 and 3 fimbriae, four siderophores, and capsular polysaccharide anchoring protein but no genes upregulating capsular polysaccharide synthesis. The Kpn_XM9 presented a classical phenotype with extreme drug resistance. The emergence of double copies of bla KPC-2 in a single plasmid from the predominant ST11 K. pneumoniae represents a new therapeutic challenge. IMPORTANCE With the wide use of ceftazidime–avibactam against carbapenem-resistant organisms, its resistance is increasingly documented; among the corresponding resistance mechanisms, mutations of bla KPC-2 or bla KPC-3 into other subtypes are dominant to date. However, more copies of bla KPC-2 may also greatly increase the minimum inhibitory concentration of ceftazidime–avibactam, which could be conferred by transposon As1 and insertion sequence 26 and should be of concern.

Cell therapy represents a promising treatment modality. A critical component in the production of cell therapy products is maintaining the sterility of cell therapy clean rooms (CTCRs). This study aimed to evaluate the environmental microbial load within CTCRs. We systematically monitored microbial load in CTCRs, following established guidelines. Cultured microbial samples underwent metagenomic sequencing, and alpha and beta diversity analyses, functional annotation, and resistance gene profiling were performed using various bioinformatics tools to assess microbial diversity and function. From November 2023 to January 2024, we collected 42 environmental microbial colony samples from various sources within the CTCR and performed metagenomic sequencing on 39 samples. Alpha diversity analysis revealed no significant differences among surface, settle_plate, and airborne categories, but significant disparities within surface subgroups were revealed. Beta diversity analysis showed notable differences between surface and airborne categories and among surface subgroups. Species distribution analysis identified Bacillus as the predominant genus on surfaces. Functional annotation and resistance gene analysis indicated distinct resistance patterns, with significant variations between subgroups, such as microscopes and transfer windows, and hands and other Grade_B environments. Resistance to hydrogen peroxide was notably higher in the transfer window group. These findings highlight the importance of stringent disinfection protocols and enhanced hand hygiene to maintain sterility in CTCRs. These findings provide valuable insights for implementing effective measures to maintain cleanliness throughout CTCRs. The annotation and study of resistance genes can help rapidly identify methods to control cellular contamination under circumstances of environmental microbial pollution. IMPORTANCE Maintaining the sterility of cell therapy clean rooms (CTCRs) is crucial for the production of safe and effective cell therapy products. Our study systematically evaluated the environmental microbial load within CTCRs, revealing significant microbial diversity and distinct resistance patterns to disinfection methods. These findings underscore the need for stringent disinfection protocols and enhanced hand hygiene practices to ensure CTCR sterility. By identifying key microbial species and their resistance genes, our research provides essential insights into controlling contamination and safeguarding the production environment, ultimately contributing to the reliability and success of cell therapy treatments.

Objective:To explore why serotype K2 accounts for a stable share in Klebsiella pneumoniae from pyogenic liver abscess (PLA). Methods:Totally 15 K2 K. pneumoniae strains from PLA, 21 K2 from non-PLA, and 31 K1 from PLA were collected from China. Sequence typing, molecular serotyping, regular PCR, and Galleria mellonella lethality were performed. A total of 12 virulence genes were detected: peg-344, allS, p-rmpA, p-rmpA2, c-rmpA, fimH, mrkD, iucA, iroN, irp2, entB, and wzi. The differences between K2 K. pneumoniae strains from PLA and non-PLA were investigated along with K1 ones. Results:Significant differences were found between K2 strains from PLA and non-PLA for the rates of virulence genes peg-344 and iucA. The latter group also showed more diverse sequence types than the former. Significant differences were only found for virulence genes allS and irp2 between K1 and K2 strains from PLA. Based on the equal virulence factors backgrounds other than serotypes, K2 strain is more virulent than K1 as G. mellonella lethality confirmed. Gene p-rmpA only brings equal virulence to p-rmpA plus p-rmpA2 in K2 strain. Conclusion:Based on the same virulence factors backgrounds except serotypes, K2 K. pneumoniae is more virulent than K1 from PLA, which provides a survival advantage to maintain a stable share.

目的 了解2015-2021年国内主要地区医疗机构临床分离链球菌属细菌对抗菌药物的耐药性.方法 对国内主要地区51所医院临床分离的链球菌属采用纸片扩散法(K-B法)或E试验方法或自动化商业药敏测试系统,按CHINET统一监测方案进行抗菌药物敏感性试验,并按2022年CLSI折点标准统计分析总结.结果 2015-2021年共收集到89 684株链球菌属细菌,包括肺炎链球菌35 254株(39.3％),β溶血链球菌42 563株(47.6％),草绿色链球菌11 767株(13.1％).42 563株β溶血链球菌中A群、B群以及未能鉴定分型的链球菌分别为39.8％、52.8％、7.4％.非脑脊液样本儿童患者分离的25 552株肺炎链球菌中青霉类敏感、中介、耐药(PSSP、PISP、PRSP)菌株的检出率分别为86.2％～97.7％、1.7％～6.5％和0.6％～7.3％,在成人患者7 997株中的检出率分别为92.0％～95.1％、3.8％～5.3％和1.4％～2.7％.脑脊液分离肺炎链球菌PRSP占比81.2％.无论是脑脊液或非脑脊液分离儿童和成人的肺炎链球菌对红霉素和克林霉素高度耐药,耐药率均在90％以上.β溶血链球菌对青霉素和头孢曲松均敏感,未发现耐药菌株;草绿色链球菌对青霉素的耐药率为5.7％～8.5％.46.3％～55.0％的B群β溶血链球菌对左氧氟沙星耐药,其他链球菌对左氧氟沙星仍十分敏感.链球菌属细菌中未发现利奈唑胺和万古霉素的耐药株.结论 青霉素仍是链球菌属非中枢神经系统感染的首选药物.链球菌属持续对红霉素、克林霉素高浓度耐药.

BackgroundBurkholderia cepacia (B. cepacia) is an emerging pathogen of nosocomial infection in pediatric patient carrying cystic fibrosis. The clinical diagnosis and treatment of B. cepacia infection remains poorly studied. This study outlined the risk factors, antimicrobial susceptibility, and clinical characteristics aiming to improve the treatment of B. cepacia infection.MethodsA retrospective study was conducted based on the 50 cases infection caused by B. cepacia in children without cystic fibrosis, which were diagnosed in the First Affiliated Hospital of Xiamen University, from January 1st, 2011 to December 31st, 2021.ResultsA total of 50 children were infected with B. cepacia, of whom 68% had an underlying health condition, such as cardiovascular disease (23.5%), respiratory disease (17.6%), nervous system disease (14.7%), and neoplastic disease (14.7%). At the onset of B. cepacia infection, 42 (84%) pediatric patients were in an intensive care unit (ICU), 33 (66%) underwent endotracheal intubation, and 32 (64%) had a central venous catheter (CVC). In addition, hospital-acquired cases were 46 (92%), and healthcare-acquired cases were 4 (12%). The most common infectious sites of B. cepacia were the respiratory tract (68%), followed by the blood (20%), and the urinary tract (12%). It indicated that B. cepacia was the most sensitive to ceftazidime (95.65%), followed by trimethoprim-sulfamethoxazole (88.68%), meropenem (82.98%), cefepime (77.78%), and levofloxacin (55.85%). The drug resistance rate of piperacillin-tazobactam, minocycline, aztreonam, cefoperazone-sulbactam and ceftriaxone was higher than 55%. 38 cases were cured or improved, eight had treatment terminated, and four died.ConclusionB. cepacia is an opportunistic pathogen normally found in immunocompromised pediatric patients and highly likely to lead to drug resistance. Nosocomial B. cepacia infections occurred mostly in patients in the ICU based on our observations. The surveillance of B. cepacia infections including changing epidemiology and increasing resistance of the microorganism is still very important. Treatment with effective antibiotics such as ceftazidime, meropenem, trimethoprim-sulfamethoxazole is associated with a favorable prognosis.

目的 了解2015-2021年我国不同地区51家医院分离的不动杆菌属分布情况和耐药变迁趋势.方法 按CHINET耐药监测方案,采用纸片扩散法或自动化仪器法对收集的菌株进行药敏试验,按CLSI 2021 年版标准判读药敏结果,采用WHONET 5.6 软件进行数据分析.结果 在此期间共分离到不动杆菌属 143 393 株,其中鲍曼不动杆菌是最常见的菌种,占所有不动杆菌属的 89.6%.呼吸道样本分离最常见的是不动杆菌属,占所有样本分离株的 73.0%.94.0%的菌株分离自住院患者,其中ICU分离的菌株占 35.5%.除米诺环素、替加环素和多黏菌素B外,不动杆菌属对其他抗菌药物如β内酰胺类、氨基糖苷类和氟喹诺酮类等耐药率较高.不同等级医院和不同科室分离的不动杆菌属对抗菌药物的耐药率存在差异.2015-2021 年鲍曼不动杆菌对头孢哌酮-舒巴坦和哌拉西林-他唑巴坦耐药率呈现上升趋势,而对替加环素和米诺环素的耐药率呈现下降趋势.碳青霉烯类耐药的鲍曼不动杆菌分离率较高,在三级医院达75.2%.结论 不动杆菌属是医院感染的重要病原菌,对临床常用抗菌药物呈现较高的耐药性.对于多重耐药不动杆菌属感染,可以采用多黏菌素B、替加环素和米诺环素等抗菌药物治疗.

目的 回顾性分析肺诺卡菌病患者的临床资料,以提高对该病的认识,并探讨病原宏基因组二代测序(metagenomic Next-Generation Sequencing,mNGS)在诺卡菌病诊断的应用价值.方法 收集2019 年 1月～2021 年8 月厦门大学附属第一医院mNGS确诊为肺诺卡菌病的13 例患者的临床资料,分析其临床特征并追踪其治疗与转归.结果 (1)13 例患者中,男性5 例,女性8 例,年龄37～78 岁,平均年龄(58±12)岁,体重指数(BMI)为(19.63±3.43)kg/m2,3 例有长期吸烟史.(2)13 例患者中只有 1 例无基础疾病,余 12 例均存在基础疾病,主要合并慢性呼吸系统疾病以及自身免疫性疾病,其中 6 例患者在进行糖皮质激素或者免疫抑制剂的治疗.(3)患者的主要临床症状包括发热、咳嗽咳痰、呼吸困难等.(4)在所有经mNGS检出的诺卡菌患者中,诺卡菌分型主要为亚洲诺卡菌.(5)9 例患者表现为双肺受累,主要表现为斑片或结节状高密度影.(6)所有患者都接受了磺胺甲噁唑治疗,大部分患者在此基础上联合其他药物治疗.结论 肺诺卡菌病多见于慢性呼吸系统疾病以及自身免疫性疾病的患者,对于这类患者,在考虑肺部感染进行常规治疗效果不佳时,应考虑到诺卡菌感染以及运用mNGS进行病原学的检测,及早的进行针对性治疗.

目的 探讨颅底内淋巴囊肿瘤(ELST)的临床特点及手术疗效.方法 回顾性分析2014年8月至2022年2月首都医科大学附属北京同仁医院神经外科联合耳鼻咽喉头颈外科手术治疗的7例ELST患者的临床资料.术前均经多学科讨论制定治疗方案.其中4例患者术前行供血动脉血管内栓塞;肿瘤最大径＜3 cm的4例患者,采用经乳突入路;≥3 cm的3例患者,1例采用经颞下窝入路,2例采用经颞下窝入路联合中颅底入路或乙状窦后入路.结果 4例患者首发症状表现为听力下降和耳鸣,1例合并von Hippel-Lindau病.术前面神经功能House-Brackmann分级Ⅰ级4例,Ⅱ级1例,Ⅳ级2例.CT主要表现为溶骨性骨质破坏;MRI表现为肿物呈囊实性,血供丰富.肿瘤最大径＜3 cm的4例患者,全切除2例,次全切除1例,大部分切除1例;≥3 cm的3例患者,全切除1例,大部分切除2例.7例患者术后中位随访时间为48个月(2个月至6年).3例全切除及1例次全切除者均无肿瘤复发.2例肿瘤大部分切除者术后接受放疗,1例肿瘤消失,随访6年无复发;1例随访3年,肿瘤有缩小趋势.1例患者术后4年死于肿瘤进展,其余6例正常生活.结论 ELST具有特征性影像学表现;多学科合作制定个体化手术治疗方案、术后残余肿瘤辅助放疗,均有助于提高患者的疗效.

目的 分析左、右侧特发性耳鸣临床特点和情绪、认知状态差异及相关性.方法 入选左、右侧耳鸣各44、36例,采集临床资料及耳鸣障碍评估量表(tinnitus handicap inventory,THI)、贝克抑郁量表(Beck depression inventory,BDI)、状态特质焦虑量表(state trait anxiety inventory,STAI)、蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)评估.结果 男性左侧耳鸣发生率明显高于女性患者(68.2％vs 31.8％).左侧耳鸣伴听力下降发生率明显高于右侧(90.9％vs 69.4％).两组间年龄、体质量指数(BMI)、受教育年限、耳鸣持续时间、听力阈值和THI、BDI、状态焦虑量表(S-AI)、特质焦虑量表(T-AI)、MoCA评分无显著性差异.影响日常生活和睡眠、抑郁、状态焦虑、特质焦虑和认知损害的发生率是23.8％、33.8％、17.5％、6.3％和33.8％.耳鸣严重程度与抑郁、状态焦虑、特质焦虑和认知功能损害呈正相关,耳聋严重程度与认知功能损害呈正相关.结论 单侧特发性耳鸣较严重,抑郁、焦虑和认知损害发生率高且与耳鸣和耳聋严重程度密切相关.

目的 探索基于镫骨肌声反射的筛选方法在非对称性耳鸣、听力下降、眩晕患者中筛选需要进行MRI检查以除外听神经瘤者.方法 回顾88例(88耳)听神经瘤患者的临床资料,分析其镫骨肌声反射的影响因素,假设三种基于镫骨肌声反射的方法筛选患者行MRI检查除外听神经瘤,并对三种筛选方法进行比较.结果 声信号频率为1 kHz时,有镫骨肌声反射22例,其中声反射阈与纯音听阈之差<60 dB者(即Metz试验阳性者)11例,介于60～95 dB之间者9例,≥95 dB者2例;无声反射66例.有无实用听力以及肿瘤分期对是否有镫骨肌声反射有显著影响,而瘤体大小对是否有声反射无显著影响.对非对称性耳鸣、听力下降、眩晕患者,除Metz试验阳性者外,均行MRI检查的筛选方法漏诊率最低(12.5％),且具有统计学意义(χ2=97.682,P=0.000).结论 建议非对称性耳鸣、听力下降、眩晕患者中除Metz试验阳性者外均行MRI检查以除外听神经瘤.

BACKGROUND:Clostridium difficile (C. difficile) is a Gram-positive, anaerobic, spore-forming bacillus that can cause pseudomembranous colitis and other C. difficile-associated diseases, resulting in significant morbidity and mortality. The incidence and clinical features vary by geography.METHODS:In this cross-sectional study, we examined the incidence and clinical features of C. difficile infection (CDI) within a 2,900-bed academic medical center in a southern area of China from January 1, 2017, to December 31, 2020. All adult inpatients (aged ≥ 18 years) who submitted loose stool samples for C. difficile testing over this period were considered for the study.RESULTS:This cross-sectional study showed that the average incidence of CDI was 2.07 cases/100,000 hospital patient-days. The mean age of these inpatients was 71.21 ± 2.83 years (range 30 - 93 years), and 83.61% (51/61) were treated in medical units. We found that 85.25% (52/61) of inpatients with CDI were aged > 60 years. Multivariate logistic regression analysis revealed that age > 60 years, and admission to the geriatric treatment unit or neurosurgery treatment unit were indeed independent risk factors for CDI in inpatients.CONCLUSIONS:The incidence of CDI in the southern area of China was low. Age > 60 years, and treatment in geriatric or neurosurgery units were independent risk factors for CDI inpatients.

New Delhi metallo-β-lactamase-13 (NDM-13) is an NDM variant that was first identified in 2015 and has not been detected in Salmonella species prior to this study. Here we describe the first identification of a Salmonella Rissen strain SR33 carrying blaNDM-13. The aim of this study was to molecularly characterize SR33’s antimicrobial resistance and virulence features as well as investigate the genetic environment of blaNDM-13. The Salmonella Rissen SR33 strain was isolated from a patient with fever and diarrhea. SR33 belonged to ST469, and it was found to be multidrug-resistant (MDR) and to carry many virulence genes. Phylogenetic analysis showed that SR33 shared a close relationship with most of the Chinese S. Rissen ST469 strains. blaNDM-13 was located in a transmissible IncI1 plasmid pNDM13-SR33. Sequence analysis of blaNDM-13-positive genomes downloaded from GenBank revealed that a genetic context (ΔISAba125-blaNDM-13-bleMBL-trpF) and a hybrid promoter (consisting of −35 sequences provided by ISAba125 and −10 sequences) were conserved. ISAba125 was truncated by IS1294 in three plasmids carrying blaNDM-13, including pNDM13-SR33. To our knowledge, this is the first report of blaNDM-13 carried by Salmonella. The emergence of blaNDM-13 in a clinical MDR S. Rissen ST469 strain highlights the critical need for monitoring and controlling the dissemination of blaNDM-13. blaNDM-13 carried by a transmissible IncI1 plasmid may result in an increased risk of blaNDM-13 transmission. IS1294 may be involved in the movement of blaNDM-13.

目的 分析应用耳模矫治器无创矫正小儿先天性耳廓形态畸形的疗效,为提高矫正效果提供指导.方法 选取2021年1-6月收治的65例(95耳)先天性耳廓形态畸形患儿为研究对象,根据年龄分为3组,≤7 d为A组(31耳),8～42 d为B组(50耳),＞42 d为C组(14耳),使用EarWell耳模矫治器治疗,记录3组患儿矫正时间、矫正效果及其并发症.结果 3组矫正时间之间比较,差异均具有统计学意义(P＜0.05),且A组时间明显短于B、C组两组;显效及治愈率3组比较均具有统计学意义(P＜0.05),且A组优于B组,B组优于C组;3组并发症发病率各组间无统计学意义(P＞0.05),并发症主要为湿疹,经涂布抗湿疹药后均于2 d内消退.结论 耳模矫治器无创矫正小儿先天性耳廓形态畸形疗效显著,年龄越小,显效及治愈率越高,矫治时间越短.

Objective To investigate the susceptibility and resistance of clinical isolates collected from hospitals in several regions of China.Methods These clinical strains were collected from 51 hospitals.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were analyzed according to CLSI 2021 breakpoints.Results A total of 301 917 clinical isolates were collected from January to December 2021,of which gram negative organisms and gram positive cocci accounted for 71.4% and 28.6% respectively.Methicillin-resistant strains in S.aureus （MRSA）,S.epidermidis and other Staphylococcus species （except S.pseudintermedius and S.schleiferi） accounted for 30.0%,80.7% and 77.7% respectively.MR strains showed much higher resistance rates to most of other antimicrobial agents than MS strains.However,92.4% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole,while 90.7% of MRSE strains were susceptible to rifampin.No staphylococcal strains were found resistant to vancomycin.E.faecalis strains demonstrated much lower resistance rates to most of the drugs tested than E.faecium.A few strains of both Enterococcus species were resistant to vancomycin.The prevalence of PSSP was 97.8% in the non-meningitis S.pneumoniae isolates from children and 95.1% in the non-meningitis S.pneumoniae isolates from adults.The Enterobacterales strains were still highly susceptible to carbapenems.Overall,less than 13% of these strains were resistant to carbapenems.K.pneumoniae isolates showed increasing resistance rates to imipenem and meropenem,from 3.0% and 2.9% in 2005 to 25.0% and 26.3% in 2018.However,the resistance rates of Klebsiella pneumoniae to imipenem and meropenem decreased since 2019.About 65.6% and 66.5% of Acinetobacter spp.were resistant to imipenem and meropenem,respectively.Overall,23.0% and 18.9% of the Pseudomonas aeruginosa isolates were resistant to imipenem and meropenem,respectively.Conclusions Bacterial resistance to commonly used antibiotics is still on the rise.However,the prevalence of carbapenem-resistant K.pneumoniae and P.aeruginosa is decreasing in recent years.It is suggested that strengthening the monitoring of bacterial resistance and multidisciplinary teamwork are effective in controlling the spread of drug-resistant bacteria.

Introduction: Talaromyces marneffei is a life-threatening pathogen that causes systemic talaromycosis in immunocompromised and acquired immunodeficiency syndrome (AIDS) patients. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a tool to cluster T. marneffei isolates is rarely reported and the data on antifungal susceptibility of T. marneffei isolated in the southern region of China, especially in Fujian, is hardly found.Methods: MALDI-TOF MS was used to cluster 135 T. marneffei isolates, and the minimum inhibitory concentration (MIC) values of with Sensititre YeastOneTM YO10 assay were measured during January 2017 to October 2020 in Fujian and Guangxi.Results: MALDI-TOF MS correctly identified 100% of the T. marneffei isolates. Hierarchical clustering of MALDI-TOF peak profiles identified four different clusters. MICs for itraconazole, posaconazole, voriconazole and amphotericin B were as follows: <= 0.015-0.03 mu g/mL, <= 0.008-0.03 mu g/mL, <= 0.008-0.06 mu g/mL, <= 0.12-1 mu g/mL, respectively. MICs for echinocandins and fluconazole were comparatively high.Conclusion: Since only simple sample preparation is required and since results are available in a short period of time, MALDI-TOF MS can be considered as a method for identification and clustering of T. marneffei. Itraconazole, posaconazole, voriconazole and amphotericin B can be used to treat T. marneffei infected patients due to the low MICs.

目的 探究重症监护病房(ICU)多重耐药菌感染患者周围致病菌环境污染情况及二氧化氯在ICU医疗环境中清洁消毒效果.方法 采用实验流行病学的方法,以厦门大学附属第一医院ICU一区为实验组,ICU二区为对照组,同时以ICU一区进行前后对照分析二氧化氯消毒较常规含氯消毒剂效果,并通过ICU二区前后对照排除时间因素及研究的霍桑效应.实验组采用现制现用的二氧化氯消毒液进行环境清洁消毒,对照组采用常规含氯消毒剂进行环境清洁消毒,对ICU一区和ICU二区进行环境卫生学采样,对比分析二氧化氯消毒剂在ICU隔离病房环境多重耐药菌清洁消毒效果.结果 ICU耐碳青霉烯类多重耐药菌感染患者隔离病房环境物表共检出耐碳青霉烯类多重耐药菌17株,多重耐药菌检出率为6.05％(17/281),其中以呼吸机表面检出率最高为16.67％(3/18),其次为隔离病房洗手池、地面均为13.79％(4/29);环境中耐碳青霉烯类多重耐药菌检出以鲍氏不动杆菌为主(8/17,47.06％),其次为耐碳青霉烯肺炎克雷伯菌(CRKP),(4/17,23.53％);ICU一区使用二氧化氯消毒剂后环境多重耐药菌检出率较常规含氯消毒剂降低(x2=3.944,P=0.047).ICU二区前后两阶段环境多重耐药菌检出率差异无统计学意义.结论 多重耐药菌感染患者隔离病房内环境物表存在一定的多重耐药菌污染,其中以呼吸机表面最严重,其次为洗手池和地面,二氧化氯对病房环境多重耐药菌清洁消毒效果优于常规含氯消毒剂.

Objectives: The aims of this study were to investigate the characteristics of Klebsiella pneumoniae meningitis and the impact of convergence of carbapenem resistance and hypervirulence on patient mortality. Methods: Antimicrobial resistance and virulence-related genes were investigated in 25 K. pneumoniae strains causing meningitis. Clinical data for 25 patients from February 2009 to February 2019 were evaluated. Multilocus sequence typing (MLST), serotyping, analysis of mobile genetic elements and pulsed-field gel electrophoresis (PFGE) were performed. GraphPad Prism was used for statistical analysis. Results: The mortality rate of patients with K. pneumoniae meningitis was 30.0%. Significant differences were observed between non-survivor and survivor groups regarding mechanical ventilation, peripheral deep vein catheter insertion and GCS score, but not sex, age or meningeal integrity destruction. Multidrug resistance was observed in 21 isolates. Rates of detection for each virulence gene ranged from 4.0% for wzy-K1 to 100.0% for entB. Detection rates of carbapenem-resistant K. pneumoniae (CRKP), hypervirulent K. pneumoniae (HvKP) and hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP) were 68.0%, 68.0% and 48.0%, respectively. In total, 16 clusters and 19 clones were identified among the 25 isolates. Mortality rates differed significantly between the non-Hv-CRKP (1/11) versus Hv-CRKP groups (5/9), but were comparable in the carbapenem-susceptible K. pneumoniae versus CRKP groups and the classical K. pneumoniae versus HvKP groups. Conclusions: Klebsiella pneumoniae meningitis is associated with high mortality. Klebsiella pneumoniae-induced meningitis has highly divergent origins. Convergence of carbapenem resistance and hypervirulence leads to high mortality in patients with K. pneumoniae meningitis, which is of great clinical concern.