National Reference Laboratory of Sexually Transmitted Diseases, National Institute of Infectious Diseases - ANLIS 'Dr Carlos G. Malbrán', Ciudad Autónoma de Buenos Aires, Argentina.
WHO Collaborating Centre for Gonorrhoea and Other STIs, Department of Laboratory Medicine, Microbiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
J Antimicrob Chemother. 2019 Jun 1;74(6):1551-1559. doi: 10.1093/jac/dkz054.
Our aim was to describe the molecular epidemiology and antimicrobial resistance determinants of isolates of Neisseria gonorrhoeae with decreased susceptibility and resistance to extended-spectrum cephalosporins (ESCs) in Argentina in 2011-16.
Gonococcal isolates (n=158) with decreased susceptibility and resistance to ESCs collected in 2011-16 across Argentina were subjected to WGS and antimicrobial susceptibility testing for six antimicrobials.
In total, 50% of the isolates were resistant to cefixime, 1.9% were resistant to ceftriaxone, 37.3% were resistant to azithromycin and 63.9% of the isolates showed an MDR phenotype. Resistance and decreased susceptibility to ESCs was mainly associated with isolates possessing the mosaic penA-34.001, in combination with an mtrR promoter A deletion, and PorB1b amino acid substitutions G120K/A121N. Phylogenetic analysis revealed two main clades of circulating strains, which were associated with the N. gonorrhoeae multiantigen sequence typing (NG-MAST) ST1407 and closely related STs, and characterized by a high prevalence rate, wide geographical distribution and temporal persistence.
N. gonorrhoeae isolates with decreased susceptibility and resistance to ESCs in Argentina have emerged and rapidly spread mainly due to two clonal expansions after importation of one or two strains, which are associated with the international MDR NG-MAST ST1407 clone. The identification of the geographical dissemination and characteristics of these predominant clones may help to focus action plans and public health policies to control the spread of ESC resistance in Argentina. Dual antimicrobial therapy (ceftriaxone plus azithromycin) for gonorrhoea needs to be considered in Argentina.
本研究旨在描述 2011-2016 年阿根廷对头孢菌素类药物（ESC）敏感性降低和耐药的淋病奈瑟菌（Neisseria gonorrhoeae）的分子流行病学和耐药决定因素。
对 2011-2016 年在阿根廷各地采集的对 ESC 敏感性降低和耐药的淋病奈瑟菌分离株进行全基因组测序（WGS）和 6 种抗菌药物的药敏试验。
总共，50%的分离株对头孢克肟耐药，1.9%对头孢曲松耐药，37.3%对阿奇霉素耐药，63.9%的分离株表现出 MDR 表型。对 ESC 的耐药性和敏感性降低主要与携带 mosaic penA-34.001 的分离株相关，同时伴有 mtrR 启动子 A 缺失和 PorB1b 氨基酸取代 G120K/A121N。系统发育分析显示，两个主要的流行株系与淋病奈瑟菌多抗原序列分型（NG-MAST）ST1407 及其密切相关的 ST 有关，其特点是流行率高、分布范围广、持续时间长。
阿根廷对 ESC 敏感性降低和耐药的淋病奈瑟菌分离株已出现并迅速传播，主要归因于两种克隆扩张，这两种扩张是由一到两个菌株的输入引起的，与国际耐药性 NG-MAST ST1407 克隆有关。这些主要克隆的地理传播和特征的鉴定可能有助于集中行动计划和公共卫生政策，以控制阿根廷 ESC 耐药的传播。阿根廷需要考虑对淋病采用双重抗菌治疗（头孢曲松加阿奇霉素）。
