NSW Health Pathology, Regional and Rural, Orange Hospital, Orange, NSW, Australia.
School of Biomedical Sciences, Charles Sturt University, Leeds Parade, Orange, NSW, 2800, Australia.
J Biomed Sci. 2022 Oct 7;29(1):78. doi: 10.1186/s12929-022-00862-7.
Escherichia coli sequence type (ST)131 is an important urinary tract pathogen, and is responsible for considerable healthcare-associated problems and costs worldwide. A better understanding of the factors that contribute to its rapid worldwide spread may help in arresting its continual spread. We studied a large collection of fecal and urinary E. coli ST131 and E. coli non-ST131 phylogenetic group B2 isolates, from women, men and children, in regional NSW, Australia.
We found out that there was a step up in ST131 prevalence (and possibly in virulence) from fecal to clinical (urinary) isolates in general, and specifically among ciprofloxacin resistant isolates, in the 3 host groups. Furthermore, our results revealed that the inferred virulence potential of the ST131 isolates (as measured by VF gene scores) was much higher than that of non-ST131 phylogenetic group B2 isolates, and this was much more pronounced amongst the urinary isolates. This finding suggests presence of possible E. coli phylogenetic B2 subgroups with varying levels of virulence, with ST131 being much more virulent compared to others. A strong association between ST131 and fluoroquinolone (FQ) resistance was also demonstrated, suggesting that FQ use is related to ST131 emergence and spread. Specifically, about 77% of ST131 isolates from women and men, and 47% from children, were extended spectrum β- lactamase (ESBL) producers. Moreover, FQ resistant ST131 ESBL isolates on average harbored more VF genes than all other isolates.
The strong association between ST131 prevalence and FQ resistance amongst the studied isolates suggests that FQ use is related to ST131 emergence and spread. Furthermore, our results demonstrate that FQ resistance and a plurality of VF genes can exist together in ST131, something that has traditionally been regarded as being inversely related. This may partly contribute to the emergence and worldwide spread of ST131.
大肠杆菌序列型（ST）131 是一种重要的尿路感染病原体，在全球范围内造成了相当多的医疗保健相关问题和成本。更好地了解导致其快速全球传播的因素可能有助于阻止其持续传播。我们研究了来自澳大利亚新南威尔士州地区的女性、男性和儿童的大量粪便和尿液大肠杆菌 ST131 和大肠杆菌非 ST131 组 B2 分离株。
我们发现，在 3 个宿主群体中，从粪便到临床（尿液）分离株，ST131 的流行率（可能还有毒力）普遍上升，特别是在环丙沙星耐药分离株中。此外，我们的结果表明，ST131 分离株的推断毒力潜力（通过 VF 基因评分测量）明显高于非 ST131 组 B2 分离株，而在尿液分离株中更为明显。这一发现表明，可能存在具有不同毒力水平的大肠杆菌 B2 亚群，而 ST131 比其他亚群更具毒力。ST131 与氟喹诺酮（FQ）耐药之间也存在很强的相关性，表明 FQ 的使用与 ST131 的出现和传播有关。具体来说，女性和男性的 ST131 分离株中约有 77%，儿童中约有 47%为产超广谱β-内酰胺酶（ESBL）的。此外，FQ 耐药的 ST131 ESBL 分离株平均携带更多的 VF 基因，比所有其他分离株都多。
在所研究的分离株中，ST131 的流行率与 FQ 耐药之间的强烈相关性表明，FQ 的使用与 ST131 的出现和传播有关。此外，我们的结果表明，FQ 耐药和多个 VF 基因可以同时存在于 ST131 中，这在传统上被认为是相反的关系。这可能在一定程度上导致了 ST131 的出现和全球传播。
