Hospital Universitario Dr. José E. González, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, Mexico.
Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, Mexico.
PLoS One. 2021 Mar 17;16(3):e0248614. doi: 10.1371/journal.pone.0248614. eCollection 2021.
This report presents phenotypic and genetic data on the prevalence and characteristics of extended-spectrum β-lactamases (ESBLs) and representative carbapenemases-producing Gram-negative species in Mexico.
A total of 52 centers participated, 43 hospital-based laboratories and 9 external laboratories. The distribution of antimicrobial resistance data for Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae complex, Acinetobacter baumannii complex, and Pseudomonas aeruginosa in selected clinical specimens from January 1 to March 31, 2020 was analyzed using the WHONET 5.6 platform. The following clinical isolates recovered from selected specimens were included: carbapenem-resistant Enterobacteriaceae, ESBL or carbapenem-resistant E. coli, and K. pneumoniae, carbapenem-resistant A. baumannii complex, and P. aeruginosa. Strains were genotyped to detect ESBL and/or carbapenemase-encoding genes.
Among blood isolates, A. baumannii complex showed more than 68% resistance for all antibiotics tested, and among Enterobacteria, E. cloacae complex showed higher resistance to carbapenems. A. baumannii complex showed a higher resistance pattern for respiratory specimens, with only amikacin having a resistance lower than 70%. Among K. pneumoniae isolates, blaTEM, blaSHV, and blaCTX were detected in 68.79%, 72.3%, and 91.9% of isolates, respectively. Among E. coli isolates, blaTEM, blaSHV, and blaCTX were detected in 20.8%, 4.53%, and 85.7% isolates, respectively. For both species, the most frequent genotype was blaCTX-M-15. Among Enterobacteriaceae, the most frequently detected carbapenemase-encoding gene was blaNDM-1 (81.5%), followed by blaOXA-232 (14.8%) and blaoxa-181(7.4%), in A. baumannii was blaOXA-24 (76%) and in P. aeruginosa, was blaIMP (25.3%), followed by blaGES and blaVIM (13.1% each).
Our study reports that NDM-1 is the most frequent carbapenemase-encoding gene in Mexico in Enterobacteriaceae with the circulation of the oxacillinase genes 181 and 232. KPC, in contrast to other countries in Latin America and the USA, is a rare occurrence. Additionally, a high circulation of ESBL blaCTX-M-15 exists in both E. coli and K. pneumoniae.
本报告介绍了墨西哥产超广谱β-内酰胺酶（ESBL）和代表性碳青霉烯酶产革兰氏阴性菌的流行情况和特征的表型和遗传数据。
共有 52 个中心参与，包括 43 个医院实验室和 9 个外部实验室。使用 WHONET 5.6 平台分析了 2020 年 1 月 1 日至 3 月 31 日从选定临床标本中分离的大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌复合群、鲍曼不动杆菌复合群和铜绿假单胞菌的抗菌药物耐药数据分布。从选定的标本中分离出以下临床分离株：耐碳青霉烯肠杆菌科、产 ESBL 或耐碳青霉烯大肠埃希菌和肺炎克雷伯菌、耐碳青霉烯鲍曼不动杆菌复合群和铜绿假单胞菌。对菌株进行基因分型以检测 ESBL 和/或碳青霉烯酶编码基因。
血液分离株中，鲍曼不动杆菌复合体对所有测试抗生素的耐药率均超过 68%，肠杆菌中阴沟肠杆菌复合体对碳青霉烯类的耐药率较高。鲍曼不动杆菌复合体对呼吸道标本的耐药模式较高，只有阿米卡星的耐药率低于 70%。在肺炎克雷伯菌分离株中，分别检测到 blaTEM、blaSHV 和 blaCTX 基因在 68.79%、72.3%和 91.9%的分离株中。在大肠埃希菌分离株中，分别检测到 blaTEM、blaSHV 和 blaCTX 基因在 20.8%、4.53%和 85.7%的分离株中。对于这两种物种，最常见的基因型均为 blaCTX-M-15。在肠杆菌科中，最常检测到的碳青霉烯酶编码基因是 blaNDM-1（81.5%），其次是 blaOXA-232（14.8%）和 blaoxa-181（7.4%），鲍曼不动杆菌是 blaOXA-24（76%），铜绿假单胞菌是 blaIMP（25.3%），其次是 blaGES 和 blaVIM（13.1%）。
本研究报告称，在墨西哥产肠杆菌科中，NDM-1 是最常见的碳青霉烯酶编码基因，同时还存在 181 和 232 两种耐青霉素酶基因。与拉丁美洲和美国的其他国家不同，KPC 的发生率较低。此外，大肠埃希菌和肺炎克雷伯菌中均存在大量 blaCTX-M-15 型 ESBL。
