Figure 2.

Pathogenesis of UTIs and uropathogenic E. coli (UPEC) adhesin structure. UTIs begin when UPEC induce periurethral invasion and colonization. Subsequent UPEC ascension into the bladder and expression of fimbriae and adhesins result in colonization and invasion of host cells and interaction with the defensive system of the bladder epithelium. UPEC produce toxins that induce host cell damage, releasing essential nutrients that promote bacterial survival and ascension to the kidneys. Kidney colonization further leads to bacterial toxin production and host tissue damage. In severe cases, it can lead to the occurrence of diseases such as bacteremia. In the abovementioned process, the structure of UPEC, including type 1 fimbriae, P fimbriae, and other fimbriae and non-fimbrial adhesins, plays an important role in the pathogenic process of UPEC.