Journal of global antimicrobial resistance最新文献_第3页

Emergence of blaKPC-71 variant and loss of aerobactin-encoding genes (iucABCD-iutA) in ST11-K64 carbapenem-resistant Klebsiella pneumoniae during ceftazidime–avibactam treatment 在头孢他啶-阿维巴坦治疗期间，ST11-K64耐碳青霉烯肺炎克雷伯菌中出现blaKPC-71变异和易动蛋白编码基因（iucABCD-iutA）的丢失

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2026-01-01 DOI: 10.1016/j.jgar.2025.11.020

Fang-ling Du , Dan-dan Wei , Yong-qing Guo , Peng Liu , Yan-fang Mei , Shan-shan Huang , Qi-sen Huang , Lin-Ping Fan , Yang Liu

Objective

To investigate the within-host evolutionary dynamics of resistance and virulence in carbapenem-resistant Klebsiella pneumoniae during ceftazidime-avibactam treatment.

Methods

Three K. pneumoniae strains were isolated from the sputum of the same patient. Broth microdilution method, whole-genome sequencing and genetic analysis were employed to clarify the dynamics and mechanisms of antibiotic resistance. Galleria mellonella infection models were used to investigate the changes in virulence.

Results

The study described the changes of three strains of ST11-K64 carbapenem-resistant K. pneumoniae associated with pulmonary infection in vivo. The transition from a ceftazidime-avibactam-susceptible but imipenem-resistant isolate (JXZRKP1) to a ceftazidime-avibactam-resistant but imipenem-susceptible isolate (JXZRKP2) was attributed to the transformation of the bla_KPC gene from bla_KPC-2 to bla_KPC-71 and upregulation of bla_KPC gene expression. Notably, the bla_KPC-71 enzyme exhibited a Ser182 duplication compared to the wild-type bla_KPC-2 carbapenemase. The bla_KPC gene of three strains was carried by the IS26-mediated tandem core structure ISKpn27-bla_KPC-IS1182 on an IncFII-type plasmid. Furthermore, in comparison with JXZRKP2, the virulence plasmid of JXZRKP3 lost the aerobactin-encoding genes (iucABCD-iutA), resulting in diminished virulence in G. mellonella infection models, but there was no significant difference(P > .05).

Conclusions

We first discovered that the mutation from bla_KPC-2 to bla_KPC-71 leads to resistance to ceftazidime-avibactam, followed by the loss of the aerobactin-encoding gene (iucABCD-iutA) on the virulence plasmid in vivo. This study underscores the complexity of addressing carbapenem-resistant K. pneumoniae infections.

目的：研究头孢他啶-阿维巴坦治疗期间耐碳青霉烯肺炎克雷伯菌在宿主内的耐药性和毒力进化动力学。方法：从同一患者的痰液中分离出3株肺炎克雷伯菌。采用微量肉汤稀释法、全基因组测序（WGS）和遗传分析阐明了抗生素耐药的动态和机制。采用大孔线虫感染模型研究其毒力变化。结果：本研究描述了3株ST11-K64耐碳青霉烯类肺炎克雷伯菌体内相关肺部感染的变化。从头孢他啶-阿维巴坦敏感但亚胺培南耐药的分离株（JXZRKP1）到头孢他啶-阿维巴坦耐药但亚胺培南敏感的分离株（JXZRKP2）的转变归因于blaKPC基因从blaKPC-2转化为blaKPC-71，并上调了blaKPC基因的表达。值得注意的是，与野生型blaKPC-2碳青霉烯酶相比，blaKPC-71酶表现出Ser182重复。三个菌株的blaKPC基因由is26介导的串联核心结构ISKpn27-blaKPC-IS1182在incfii型质粒上携带。此外，与JXZRKP2相比，JXZRKP3的毒力质粒丢失了需氧肌动蛋白编码基因（iucABCD-iutA），导致在mellonella感染模型中的毒力降低，但差异无统计学意义（P < 0.05）。结论：我们首先发现从blaKPC-2到blaKPC-71突变导致对头孢他啶-阿维巴坦耐药，随后在体内发现毒质粒上的好氧肌动蛋白编码基因（iucABCD-iutA）缺失。这项研究强调了解决耐碳青霉烯肺炎克雷伯菌感染的复杂性。

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引用次数: 0

First identification of a multidrug-resistant Pseudomonas kurunegalensis clinical isolate co-carrying blaAFM-1 and blaIMP-1 in China 中国首次发现一株多重耐药库鲁egalensis假单胞菌临床分离株共携带blaAFM-1和blaIMP-1。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2026-01-01 DOI: 10.1016/j.jgar.2025.12.007

Shuwei Fan , Yuzhuo Gong , Chunxiao Chen , Jingchao Shi , Cong Wu

Objectives

The objective of this study was to elucidate the genetic context and characterize chromosome co-carrying bla_AFM-1 and bla_IMP-1 in a multidrug-resistant Pseudomonas kurunegalensis (P. kurunegalensis) isolate obtained from human urine using whole-genome sequencing.

Methods

This P. kurunegalensis isolate JC172 co-harbouring bla_AFM-1 and bla_IMP-1 underwent a comprehensive investigation that included antimicrobial susceptibility testing, conjugation assays, whole-genome sequencing and bioinformatic analyses. To depict the evolutionary dynamics of P. kurunegalensis strains on a global scale, a phylogenetic tree was generated based on single nucleotide polymorphisms of core genomes.

Results

JC172 was classified as P. kurunegalensis based on sequencing results and average nucleotide identity (ANI) assessments. This isolate was designated as ST114 and possesses a chromosome with 5 855 340 base pairs, exhibiting a GC content of 61.9%. Several resistance genes, including bla_AFM-1 and bla_IMP-1, bla_OXA-246 and tmexC3D2-toprJ1 were identified on the chromosome. Genomic analysis revealed that bla_AFM-1 was situated within a core module of the TnAs3-bla_AFM-1 unit, which is bordered by class 1 integrons. This arrangement implies a significant potential for bla_AFM-1 dissemination.

Conclusions

Our study revealed that bla_AFM-1 and bla_IMP-1, bla_OXA-246 and tmexC3D2-toprJ1 were harboured by P. kurunegalensis. We suggested that ST114 P. kurunegalensis may serve as a reservoir for resistance genes.

目的：本研究的目的是利用全基因组测序技术，阐明从人类尿液中获得的多重耐药kurunegalensis假单胞菌（P. kurunegalensis）的遗传背景和染色体共携带blaAFM-1和blaIMP-1的特征。方法：对共携带blaAFM-1和blaIMP-1的kurunegalensis分离株JC172进行药敏试验、偶联试验、全基因组测序和生物信息学分析。为了描述p.k urunegalensis菌株在全球范围内的进化动态，基于核心基因组的单核苷酸多态性构建了系统发育树。结果：根据测序结果和平均核苷酸同源性（ANI）鉴定，JC172属kurunegalensis。该分离物被命名为ST114，具有一条5,855,340对碱基对的染色体，GC含量为61.9%。在染色体上鉴定出blaAFM-1和blaIMP-1、blaOXA-246和tmexc32d - toprj1等抗性基因。基因组分析显示，blaAFM-1位于TnAs3-blaAFM-1单元的核心模块中，该单元与1类整合子相邻。这种安排意味着blaAFM-1传播的巨大潜力。结论：我们的研究表明，blaAFM-1、blaIMP-1、blaOXA-246和tmexc32d - toprj1在库鲁尼加疟原虫中存在。我们认为ST114库鲁egalensis可能是抗性基因的储存库。

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引用次数: 0

Multicentric evaluation of the MTS™ Synergy Application System for reliable antibiotic synergy testing in clinical laboratories 多中心评价MTS-SAS®在临床实验室可靠的抗生素协同试验。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2026-01-01 DOI: 10.1016/j.jgar.2025.12.010

Edoardo Carretto , Stefano Andreoni , Richard Aschbacher , Daniela Barbarini , Simone Bramati , Flavia Brovarone , Claudio Farina , Angela Papa , Andrea Rocchetti , Giuseppe Russello , Vittorio Sambri , Assunta Sartor , Paolo Gaibani

Objectives

The rise of antimicrobial resistance poses a major challenge for both clinicians and clinical microbiologists. There is an increasing need for user-friendly and reliable methods to assess the activity of antibiotics against multidrug-resistant (MDR) strains. Although synergy testing provides valuable insights, conventional methods such as checkerboard assays and time-kill studies are labour-intensive, technically demanding, and difficult to standardize. This study evaluated the MTS™ SAS (MIC Test Strip – Synergy Application System, Liofilchem, Italy), a commercial gradient diffusion assay developed for antibiotic synergy testing.

Methods

The performance of MTS™ SAS was evaluated in comparison with the checkerboard microdilution method, used as the reference standard. Nine antibiotic combinations were tested against ten different bacterial strains across 11 Italian hospitals. Inter-laboratory reproducibility and agreement with the reference method were analysed.

Results

The concordance between MIC test strips and the broth microdilution (BMD) method was 98.4%, with 1.6% showing discordant results – all within a 3-dilution range. Among 996 synergy determinations, MTS™ SAS demonstrated high reproducibility across all centers (96.7%), while only 3.3% of tests showed discordant synergy classifications (e.g., synergy vs. indifference). Comparison with the checkerboard method demonstrated an overall concordance of 96.2%, despite the absence of specific operator training at each site.

Conclusion

These findings support MTS™ SAS as a practical and reliable alternative to conventional synergy testing methods, particularly suitable for routine clinical settings and laboratories lacking advanced microbiological expertise.

目的：抗菌素耐药性的上升对临床医生和临床微生物学家提出了重大挑战。越来越需要用户友好和可靠的方法来评估抗生素对多药耐药菌株的活性。尽管协同测试提供了有价值的见解，但诸如棋盘分析和耗时研究之类的传统方法是劳动密集型的，技术要求高，并且难以标准化。本研究评估了MTS-SAS®（MIC试纸-协同应用系统，Liofilchem®，意大利），这是一种用于抗生素协同测试的商业梯度扩散试验。方法：将MTS-SAS®与棋盘格微量稀释法进行比较，并作为对照标准。在意大利11家医院对9种抗生素组合进行了针对10种不同菌株的测试。分析了该方法的实验室间重复性及与参考方法的一致性。结果：MIC试纸与微量肉汤稀释法（BMD）的一致性为98.4%，结果不一致的为1.6%，均在3倍稀释范围内。在996个协同作用测定中，MTS-SAS®在所有中心显示出高重复性（96.7%），而只有3.3%的试验显示出不一致的协同作用分类（例如，协同作用与无差异）。与棋盘法相比，尽管在每个站点缺乏具体的操作人员培训，但总体一致性为96.2%。结论：这些发现支持MTS-SAS®作为传统协同检测方法的实用可靠的替代方法，特别适用于常规临床环境和缺乏先进微生物专业知识的实验室。

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引用次数: 0

Clinical outcome comparison between adjunctive clindamycin vs linezolid for invasive group A streptococcal infection. 辅助克林霉素与利奈唑胺治疗侵袭性A组链球菌感染的临床结果比较。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-22 DOI: 10.1016/j.jgar.2025.12.013

Eriko Hashimoto, Sayaka Yoshida, Taito Kitano

Purpose: Although the non-inferiority of adjunctive linezolid (LZD) was indicated for the treatment of invasive group A streptococcal (iGAS) infection, compared with adjunctive clindamycin (CLDM), additional evaluation of comparative effectiveness by subpopulation may further strengthen the evidence. We compared the efficacy of CLDM and LZD combination therapy for iGAS infection.

Methods: In this retrospective cohort study, data were extracted and analyzed using TriNetX, a multicenter database. Data were extracted from January 1, 2015, to April 30, 2025, creating two cohorts (adjunctive CLDM and LZD groups). The primary endpoint was mortality within 90 days from diagnosis, which was compared between groups using propensity score matching (PSM). Subgroup analyses were conducted according to age, concomitant intravenous immunoglobulin (IVIG) treatment, and study period.

Results: For analysis, 5,841 cases were identified in the CLDM combination group and 1,426 in the LZD group. The primary endpoint was observed in 170 (12.0%) cases in the CLDM group and 195 (13.8%) in the LZD group. Odds ratio (OR) was 0.854 (95% confidence interval 0.685-1.065, p=0.161), with OR<1 indicating a CLDM-favorable result.

Conclusion: Clinical efficacy of adjunctive CLDM and LZD was compared in patients with iGAS infection. No significant difference in mortality was observed in the overall population. LZD may be a potential alternative in cases where CLDM use is limited by resistance, intolerance, or contraindications.

目的：虽然与辅助克林霉素（CLDM）相比，辅助利奈唑胺（LZD）治疗侵袭性A组链球菌（iGAS）感染具有非劣效性，但对亚群比较效果的额外评价可能会进一步加强证据。我们比较了CLDM和LZD联合治疗iGAS感染的疗效。方法：在这项回顾性队列研究中，使用TriNetX多中心数据库提取数据并进行分析。数据从2015年1月1日至2025年4月30日提取，创建两个队列（辅助CLDM组和LZD组）。主要终点是诊断后90天内的死亡率，使用倾向评分匹配（PSM）进行组间比较。根据年龄、同时静脉注射免疫球蛋白（IVIG）治疗和研究时间进行亚组分析。结果：在分析中，CLDM联合组有5841例，LZD组有1426例。CLDM组170例（12.0%）和LZD组195例（13.8%）观察到主要终点。优势比（OR）为0.854(95%可信区间0.685-1.065,p=0.161)， OR。结论：比较iGAS感染患者辅助CLDM与LZD的临床疗效。在总体人群中没有观察到死亡率的显著差异。如果CLDM的使用受到耐药性、不耐受或禁忌症的限制，LZD可能是一种潜在的替代方案。

{"title":"Clinical outcome comparison between adjunctive clindamycin vs linezolid for invasive group A streptococcal infection.","authors":"Eriko Hashimoto, Sayaka Yoshida, Taito Kitano","doi":"10.1016/j.jgar.2025.12.013","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.12.013","url":null,"abstract":"<p><strong>Purpose: </strong>Although the non-inferiority of adjunctive linezolid (LZD) was indicated for the treatment of invasive group A streptococcal (iGAS) infection, compared with adjunctive clindamycin (CLDM), additional evaluation of comparative effectiveness by subpopulation may further strengthen the evidence. We compared the efficacy of CLDM and LZD combination therapy for iGAS infection.</p><p><strong>Methods: </strong>In this retrospective cohort study, data were extracted and analyzed using TriNetX, a multicenter database. Data were extracted from January 1, 2015, to April 30, 2025, creating two cohorts (adjunctive CLDM and LZD groups). The primary endpoint was mortality within 90 days from diagnosis, which was compared between groups using propensity score matching (PSM). Subgroup analyses were conducted according to age, concomitant intravenous immunoglobulin (IVIG) treatment, and study period.</p><p><strong>Results: </strong>For analysis, 5,841 cases were identified in the CLDM combination group and 1,426 in the LZD group. The primary endpoint was observed in 170 (12.0%) cases in the CLDM group and 195 (13.8%) in the LZD group. Odds ratio (OR) was 0.854 (95% confidence interval 0.685-1.065, p=0.161), with OR<1 indicating a CLDM-favorable result.</p><p><strong>Conclusion: </strong>Clinical efficacy of adjunctive CLDM and LZD was compared in patients with iGAS infection. No significant difference in mortality was observed in the overall population. LZD may be a potential alternative in cases where CLDM use is limited by resistance, intolerance, or contraindications.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145827940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Detection of clinical isolates of tigecycline-resistant Escherichia coli harboring tet(X4) in Myanmar. 缅甸耐替加环素携带tet（X4）大肠杆菌临床分离株检测。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-16 DOI: 10.1016/j.jgar.2025.12.006

Maiko Kirikae, Satomi Takei, Thi Thi Htoon, Pan Ei Soe, Nang Sarm Hom, San Yu Maw, May Yee Aung, Shino Hosoya, Swe Setk, Htay Htay Tin, Yuki Uehara, Teruo Kirikae, Tatsuya Tada

Objectives: Tigecycline is one of the last-resort antibiotics for treating serious infections caused by multidrug-resistant pathogens. This is the first report of clinical isolates of tigecycline-resistant Escherichia coli harboring tet(X4) in Myanmar.

Methods: Two E. coli isolates were obtained from two patients at two hospitals in Myanmar from November 2023 to May 2024. They were identified using MALDI-TOF MS, and minimum inhibitory concentrations (MICs) were determined using the broth microdilution method. Genomic DNA was extracted and sequenced using next generation sequencing. Drug-resistance factors were determined, and the genetic environments surrounding tet(X4) and bla_NDM-5 were analyzed. Conjugation rates of plasmids harboring tet(X4) and bla_NDM-5 were calculated.

Results: One strain, TGH62, was resistant to tigecycline (MIC 8 µg/ml) and meropenem (MIC 128 µg/ml), whereas the other, YGH433, was resistant to tigecycline (MIC 4 µg/ml). Whole-genome sequencing revealed that both strains harbored tet(X4) on plasmids and TGH62 also harbored bla_NDM-5 on a plasmid. The plasmids carrying tet(X4) in TGH62 and YGH433 belonged to the IncI and IncFII incompatibility groups, respectively. The plasmid carrying bla_NDM-5 belonged to the IncFIA incompatibility group. The conjugation efficiencies of the plasmids harboring tet(X4) in YGH433 and bla_NDM-5 in TGH62 were relatively high, whereas that harboring tet(X4) in TGH62 was low.

Conclusions: Tigecycline-resistant Enterobacteriaceae harboring tet(X4) may spread in hospitals in Myanmar. Further studies are needed to detect tet(X4) conferring tigecycline resistance in hospitals as well as environmental settings in Myanmar.

目的：替加环素是治疗多重耐药病原菌引起的严重感染的最后抗生素之一。这是缅甸首次报道携带tet（X4）的耐替加环素大肠杆菌临床分离株。方法：2023年11月至2024年5月，从缅甸两家医院的2例患者中分离出2株大肠杆菌。用MALDI-TOF质谱法鉴定，用肉汤微量稀释法测定最低抑菌浓度（mic）。提取基因组DNA，采用下一代测序技术进行测序。测定耐药因素，分析tet（X4）和blaNDM-5的遗传环境。计算携带tet（X4）和blaNDM-5的质粒的结合率。结果：菌株TGH62对替加环素（MIC为8µg/ml）和美罗培南（MIC为128µg/ml）耐药，菌株YGH433对替加环素（MIC为4µg/ml）耐药。全基因组测序显示，这两种菌株的质粒上都含有tet(X4)， TGH62的质粒上也含有blaNDM-5。TGH62和YGH433中携带tet（X4）的质粒分别属于IncI和IncFII不相容组。携带blaNDM-5的质粒属于IncFIA不相容组。在YGH433中携带tet（X4）的质粒和在TGH62中携带blaNDM-5的质粒结合效率较高，而在TGH62中携带tet（X4）的质粒结合效率较低。结论：携带tet（X4）的耐替加环素肠杆菌科可能在缅甸医院传播。需要进一步的研究来发现在缅甸的医院和环境环境中造成替加环素耐药性的tet（X4）。

{"title":"Detection of clinical isolates of tigecycline-resistant Escherichia coli harboring tet(X4) in Myanmar.","authors":"Maiko Kirikae, Satomi Takei, Thi Thi Htoon, Pan Ei Soe, Nang Sarm Hom, San Yu Maw, May Yee Aung, Shino Hosoya, Swe Setk, Htay Htay Tin, Yuki Uehara, Teruo Kirikae, Tatsuya Tada","doi":"10.1016/j.jgar.2025.12.006","DOIUrl":"https://doi.org/10.1016/j.jgar.2025.12.006","url":null,"abstract":"<p><strong>Objectives: </strong>Tigecycline is one of the last-resort antibiotics for treating serious infections caused by multidrug-resistant pathogens. This is the first report of clinical isolates of tigecycline-resistant Escherichia coli harboring tet(X4) in Myanmar.</p><p><strong>Methods: </strong>Two E. coli isolates were obtained from two patients at two hospitals in Myanmar from November 2023 to May 2024. They were identified using MALDI-TOF MS, and minimum inhibitory concentrations (MICs) were determined using the broth microdilution method. Genomic DNA was extracted and sequenced using next generation sequencing. Drug-resistance factors were determined, and the genetic environments surrounding tet(X4) and bla<sub>NDM-5</sub> were analyzed. Conjugation rates of plasmids harboring tet(X4) and bla<sub>NDM-5</sub> were calculated.</p><p><strong>Results: </strong>One strain, TGH62, was resistant to tigecycline (MIC 8 µg/ml) and meropenem (MIC 128 µg/ml), whereas the other, YGH433, was resistant to tigecycline (MIC 4 µg/ml). Whole-genome sequencing revealed that both strains harbored tet(X4) on plasmids and TGH62 also harbored bla<sub>NDM-5</sub> on a plasmid. The plasmids carrying tet(X4) in TGH62 and YGH433 belonged to the IncI and IncFII incompatibility groups, respectively. The plasmid carrying bla<sub>NDM-5</sub> belonged to the IncFIA incompatibility group. The conjugation efficiencies of the plasmids harboring tet(X4) in YGH433 and bla<sub>NDM-5</sub> in TGH62 were relatively high, whereas that harboring tet(X4) in TGH62 was low.</p><p><strong>Conclusions: </strong>Tigecycline-resistant Enterobacteriaceae harboring tet(X4) may spread in hospitals in Myanmar. Further studies are needed to detect tet(X4) conferring tigecycline resistance in hospitals as well as environmental settings in Myanmar.</p>","PeriodicalId":15936,"journal":{"name":"Journal of global antimicrobial resistance","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145781088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Genomic and phylogenetic analysis of a carbapenem-resistant Raoultella ornithinolytica clinical isolate carrying blaOXA-181 from China 中国携带blaOXA-181的耐碳青霉烯型溶鸟拉乌尔菌临床分离株的基因组和系统发育分析

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-02 DOI: 10.1016/j.jgar.2025.11.019

Zhiqiang Zhu , Xiaofei Zhao , Zhaokun Fan , Ying Fu , Xi Li , Meizhen Ye

Objective

Raoultella ornithinolytica, a species within Enterobacteriaceae, is rarely multidrug-resistant. Here, we report a carbapenem-resistant R. ornithinolytica carrying bla_OXA-181 and elucidate its genomic characteristics for the first time in China.

Methods

Antimicrobial susceptibility testing and hybrid whole-genome sequencing were conducted on the R. ornithinolytica strain CRRAO31010. Comprehensive in silico analyses of virulence determinants, resistance genes, and their genetic contexts were performed. Conjugation experiments were conducted with Escherichia coli J53 as the recipient to assess the transferability of bla_OXA-181. In addition, we combined our isolate with 56 R. ornithinolytica strains bearing the bla_OXA-181 gene retrieved from the NCBI database for phylogenetic analysis.

Results

R. ornithinolytica strain CRRAO31010 is a carbapenem-resistant strain characterized by its production of the OXA-181 enzyme, which confers resistance to multiple antibiotics. WGS revealed 22 antimicrobial resistance genes in CRRAO31010, including bla_OXA-181 carried on a ColKP3-IncX3 hybrid plasmid. This plasmid was conjugated into E. coli J53 with a conjugation frequency of approximately 2.5 × 10⁻⁶ per donor cell. Phylogenetic analysis revealed that the earliest R. ornithinolytica strain carrying the bla_OXA-181 gene was detected in the United Kingdom in 2019. The United States had the highest number of OXA-181-carrying R. ornithinolytica strains. Notably, IncX3-type plasmids had the highest prevalence (96.49%, 55/57) among these isolates.

Conclusions

We report the first carbapenem-resistant R. ornithinolytica strain harbouring the bla_OXA-181 gene on a ColKP3-IncX3 hybrid plasmid from China. Given the high conjugative potential of IncX3 plasmids, vigilance is required to monitor the dissemination of such resistance determinants within R. ornithinolytica.

目的：溶鸟拉乌尔菌是肠杆菌科的一种罕见的多重耐药菌。本文报道了一株携带blaOXA-181的耐碳青霉烯型溶鸟盲蝽，并在国内首次阐明了其基因组特征。方法：对溶鸟毒R. CRRAO31010进行药敏试验和杂交全基因组测序。对毒力决定因素、抗性基因及其遗传背景进行了全面的计算机分析。以大肠杆菌J53为受体进行偶联实验，评估blaOXA-181的可移植性。此外，我们将分离物与从NCBI数据库中检索到的56株携带blaOXA-181基因的溶鸟单胞菌进行系统发育分析。结果：鸟毒R. ornithinolytica菌株CRRAO31010是一株碳青霉烯耐药菌株，其特征是产生OXA-181酶，对多种抗生素具有耐药性。WGS在CRRAO31010中发现22个耐药基因，其中包括ColKP3-IncX3杂交质粒上携带的blaOXA-181。该质粒被偶联到大肠杆菌J53中，偶联频率约为2.5×10-6 /供体细胞。系统发育分析显示，最早携带blaOXA-181基因的禽毒r于2019年在英国检测到。美国携带oxa -181的禽毒r菌株数量最多。其中，incx3型质粒的感染率最高（96.49%,55/57）。结论：在中国ColKP3-IncX3杂交质粒上发现了首株含有blaOXA-181基因的耐碳青霉烯型溶鸟单胞菌。考虑到IncX3质粒的高结合潜力，需要警惕地监测这些耐药决定因素在溶鸟盲蝽体内的传播。

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引用次数: 0

ISAC News and Updates ISAC新闻和更新

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-01 DOI: 10.1016/j.jgar.2025.11.012

引用次数: 0

Knowledge, attitudes, and practices regarding antibiotic use and resistance in ruminants and chickens among prescribers and farmers in Bangladesh 孟加拉国开处方者和农民关于反刍动物和鸡抗生素使用和耐药性的知识、态度和做法。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-01 DOI: 10.1016/j.jgar.2025.10.020

Mohammed Lutfur Rahman , Md. Irtija Ahsan , Sultan Ahmed , Md. Khademul Islam , A.T.M. Mahbub-E-Elahi , Md Bashir Uddin , Syed Sayeem Uddin Ahmed

Objectives

This study employed the knowledge, attitudes, and practices (KAP) to investigate antibiotic usage in ruminants and chickens farming by various prescribers and farmers.

Methods

A cross-sectional survey was conducted across 64 sub-districts in eight divisions of Bangladesh, assessing the KAP concerning antibiotic use (ABU) and antibiotic resistance (ABR) through a pretested questionnaire. A total of 1248 participants took part in the KAP survey. Data collection methods included face-to-face interactions, email, and courier services, followed by subsequent analysis.

Results

The results revealed that registered veterinarians achieved a 100% knowledge score regarding recommended doses and standard practices. While farmers and informal practitioners generally agreed with some antibiotic practices, 10.71% recognized the importance of withdrawal periods, 11.07% acknowledged public health risks, and 5.71% understood the residual effects of antibiotics. Similarly, among informal practitioners, awareness was low, with only 14.46%, 16.75%, and 7.71%, respectively. These findings show that many farmers and informal practitioners have limited KAP regarding antibiotic use and resistance. The analysis showed that demographic factors, such as education had a significant impact on participants' KAP (OR = 8.06; 95% CI: 6.07–10.70; P < 0.001) regarding ABU and ABR. In particular, registered veterinarians were nearly three times more likely to have accurate KAP compared to those with lower education levels (aOR = 2.78; 95% CI: 1.94-4.00; P < 0.001). Importantly, the correlation matrix indicated strong and statistically significant positive relationships among knowledge, attitudes, and practices (P < 0.001).

Conclusion

These findings demonstrate a strong interplay between knowledge, attitudes, and practices regarding ABU and ABR in ruminants and chickens.

目的：本研究采用知识、态度和实践（KAP）调查不同处方医师和农民在反刍动物和鸡养殖中抗生素的使用情况。方法：在孟加拉国8个省的64个街道进行横断面调查，通过预测问卷评估有关抗生素使用（ABU）和抗生素耐药性（ABR）的KAP。共有1248人参与了KAP的调查。数据收集方法包括面对面互动、电子邮件和快递服务，然后进行后续分析。结果：结果显示，注册兽医在推荐剂量和标准做法方面的知识得分达到100%。虽然农民和非正式从业人员普遍同意一些抗生素做法，但10.71%的人认识到停药期的重要性，11.07%的人认识到公共卫生风险，5.71%的人了解抗生素的残留效应。同样，在非正式从业人员中，意识也很低，分别只有14.46%、16.75%和7.71%。这些发现表明，许多农民和非正规从业人员对抗生素使用和耐药性的了解有限。分析表明，人口统计学因素，如教育对参与者的KAP （OR=8.06; 95% CI: 6.07-10.70; p< 0.001）对ABU和ABR有显著影响。特别是，注册兽医拥有准确KAP的可能性是受教育程度较低的人的近三倍（aOR = 2.78;95% CI: 1.94-4.00; p< 0.001）。重要的是，相关矩阵显示知识、态度和实践之间存在显著的正相关关系(p结论：这些发现表明反刍动物和鸡对ABU和ABR的知识、态度和实践之间存在很强的相互作用。

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引用次数: 0

Reviewer Acknowledgement 2025 审稿人致谢2025

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-12-01 DOI: 10.1016/j.jgar.2025.11.017

引用次数: 0

Clonal diversity and plasmid-mediated emergence of NDM-1-producing Raoultella ornithinolytica in clinical isolates 产ndm -1的溶鸟劳氏菌临床分离株的克隆多样性和质粒介导的出现。

IF 3.2 3区医学 Q2 INFECTIOUS DISEASES

Journal of global antimicrobial resistance

Pub Date : 2025-11-29 DOI: 10.1016/j.jgar.2025.11.018

Jin Seok Kim , Young Hee Jin , So Youn Park , Hyo-Won Jeong , Jinwoo Kim , Sook Hyun Park , Chang-Kyu Kim , YoungAh Yoo , Young Kyung Yoon , Jae In Lee , Jihun Jung , Ju-Sung Park

Objective

Raoultella ornithinolytica is recognized as an emerging opportunistic pathogen, with sporadic reports of multidrug resistance. However, comprehensive analyses of carbapenem-resistant isolates remain limited. This study investigated the molecular features and plasmid-mediated transmission of bla_NDM-1 among clonally distinct clinical isolates of R. ornithinolytica in Seoul, South Korea.

Methods

All 13 carbapenem-resistant R. ornithinolytica isolates referred to the central reference laboratory in Seoul from seven hospitals between 2018 and 2020 were analysed. Isolates were characterized using antimicrobial susceptibility testing, resistance gene detection, plasmid replicon typing, pulsed-field gel electrophoresis, conjugation assays, and whole-genome sequencing.

Results

Among the 13 isolates, 10 harboured bla_NDM-1, seven of which carried the gene on IncX3 plasmids. Despite clonal diversity, six of the 13 isolates shared nearly identical transferable IncX3 plasmids of approximately 45 kb, indicating horizontal plasmid dissemination among non-clonal strains. A novel bla_NDM-1 configuration, IS3000–∆ISAba125–IS1A–bla_NDM-1–ble_MBL–trpF, was found in both R. ornithinolytica and Enterobacter cloacae from a single hospital, including two patients with co-infection. These findings highlighting the key role of IncX3 plasmids in rapid dissemination of bla_NDM-1 across species boundaries.

Conclusions

This study demonstrates the contribution of IncX3 plasmids to the intra- and interspecies spread of bla_NDM-1, underscoring the need for enhanced genomic surveillance of emerging pathogens such as R. ornithinolytica to limit carbapenem resistance transmission in clinical settings.

目的：溶鸟劳氏菌被认为是一种新兴的机会性病原体，有零星的多药耐药报告。然而，对碳青霉烯耐药菌株的综合分析仍然有限。本研究在韩国首尔研究了blaNDM-1在不同克隆临床分离株中的分子特征和质粒介导的传播。方法：对2018 - 2020年首尔市7家医院收治的13株耐碳青霉烯类溶鸟嘌呤单胞菌进行分析。对分离菌株进行了抗菌药敏试验、抗性基因检测、质粒复制子分型、脉冲场凝胶电泳、偶联试验和全基因组测序。结果：13株分离株中有10株携带blaNDM-1基因，其中7株在IncX3质粒上携带该基因。尽管存在克隆多样性，但13株分离株中有6株具有几乎相同的可转移IncX3质粒，约为45 kb，表明质粒在非克隆菌株中水平传播。一种新的blaNDM-1构型为IS3000-∆isaba125 - is1a -blaNDM-1- blemlb - trpf，在一家医院的溶鸟鼻杆菌和阴沟肠杆菌中均被发现，包括两名合并感染的患者。这些发现突出了IncX3质粒在blaNDM-1跨物种快速传播中的关键作用。结论：本研究证明了IncX3质粒对blaNDM-1的种内和种间传播的贡献，强调了加强对新出现的病原体（如溶鸟瘟菌）的基因组监测的必要性，以限制临床环境中碳青霉烯类耐药性的传播。

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