Urinary tract infections (UTIs) are the most common infectious disease and are mainly caused by Escherichia coli. In this review, we introduce the current concept of recurrent UTI (rUTI) based on recent research dealing with pathophysiology of the disease. Although urine is considered sterile, recent studies dealing with microbiome have proposed different ideas. UTIs have typically been considered as extracellular infections, but recently, uropathogenic Escherichia coli (UPEC) has been shown to bind and replicate in the urothelium to make intracellular bacterial communities (IBCs). Binding UPECs might proceed in many ways including extracellular expulsion for clearance or survival and quiescent intracellular reservoirs that can cause rUTI. Moreover, it is also suggested that other important factors, such as lipopolysaccharide and multi-microbial infection, can be the cause of rUTI. This review article reveals a key mechanism of recurrence and discusses what makes a pathway of resolution or recurrence in a host after initial infection.

中文翻译：

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反复尿路感染的原因是什么？病理生理学的当代微观概念。

尿路感染（UTI）是最常见的传染病，主要由大肠杆菌引起。在这篇综述中，我们根据最近处理该疾病病理生理学的研究介绍了当前复发性尿路感染 (rUTI) 的概念。尽管尿液被认为是无菌的，但最近关于微生物组的研究提出了不同的想法。UTI 通常被认为是细胞外感染，但最近，尿路致病性大肠杆菌 (UPEC) 已被证明可以在尿路上皮中结合和复制，从而形成细胞内细菌群落 (IBC)。结合 UPEC 可能以多种方式进行，包括用于清除或存活的细胞外排出和可导致 rUTI 的静止细胞内储库。此外，还建议其他重要因素，如脂多糖和多种微生物感染，可能是 rUTI 的原因。这篇综述文章揭示了复发的一个关键机制，并讨论了是什么导致了宿主在初始感染后消退或复发的途径。