Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", CDMX, México.
Laboratorio de Inmunidad en Mucosas, Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, México.
PLoS One. 2018 Oct 4;13(10):e0204934. doi: 10.1371/journal.pone.0204934. eCollection 2018.
The Hospital Infantil de México Federico Gómez (HIMFG) is a tertiary care hospital in Mexico City where Escherichia coli is frequently isolated from the urine samples of pediatric patients with urinary tract infections. A collection of 178 urinary Escherichia coli (UEc) isolates associated with complicated and uncomplicated urinary tract infections were evaluated in this study. The patterns of resistance to 9 antibiotic classes showed that 60.7% of the UEc isolates had a highly multidrug-resistant (MDR) profile. Genetic diversity analyses of the UEc isolates showed a high variability and revealed 16 clusters associated with four phylogenetic groups, namely, groups A, B1, B2, and D. Phylogenetic group B2 was widely associated with the 16 clusters as well as with virulence and fitness genes. The virulence and fitness genes in the UEc isolates, which included fimbriae-, siderophore-, toxin-, and mobility-associated genes, were grouped as occurring at a low, variable, or high frequency. Interestingly, only the papF gene could be amplified from some UEc isolates, and the sequence analysis of the pap operon identified an insertion sequence (IS) element and gene loss. These data suggested pathoadaptability and the development of immune system evasion, which was confirmed by the loss of P fimbriae-associated agglutination in the UEc isolates. E. coli clone O25-ST131 had a prevalence of 20.2% among the UEc isolates; these isolates displayed both a highly MDR profile and the presence of the papGII, fimH, papGIII, iutD, sat, hlyA, and motA genes. In conclusion, the UEc isolates from complicated urinary tract infection (cUTI) were characterized as being MDR, highly genetically diverse, and associated with phylogenetic group B2 and many virulence and fitness genes. Additionally, gene loss and IS elements were identified in some UEc isolates identified as clone O25-ST131.
墨西哥城费德里科·戈麦斯儿童总医院（HIMFG）是一家三级保健医院，常从患有尿路感染的儿科患者的尿液样本中分离出大肠杆菌。本研究评估了 178 株与复杂性和非复杂性尿路感染相关的尿大肠杆菌（UEc）分离株。对 9 类抗生素的耐药模式进行分析显示，60.7%的 UEc 分离株具有高度多重耐药（MDR）特征。对 UEc 分离株的遗传多样性分析显示出高度的变异性，并揭示了与 4 个进化群相关的 16 个聚类，即 A、B1、B2 和 D 群。B2 群与 16 个聚类以及毒力和适应性基因广泛相关。UEc 分离株中的毒力和适应性基因，包括菌毛、铁载体、毒素和移动相关基因，被归类为低、可变或高频率出现。有趣的是，只有 papF 基因可以从一些 UEc 分离株中扩增出来，而 pap 操纵子的序列分析确定了插入序列（IS）元件和基因缺失。这些数据表明了病原体的适应性和免疫系统逃避的发展，这在 UEc 分离株中 P 菌毛相关凝集的丧失中得到了证实。大肠杆菌克隆 O25-ST131 在 UEc 分离株中的流行率为 20.2%；这些分离株表现出高度的 MDR 特征，并且存在 papGII、fimH、papGIII、iutD、sat、hlyA 和 motA 基因。总之，复杂性尿路感染（cUTI）的 UEc 分离株具有 MDR、高度遗传多样性的特点，与 B2 群和许多毒力和适应性基因相关。此外，在一些被鉴定为 O25-ST131 克隆的 UEc 分离株中发现了基因缺失和 IS 元件。
