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Along the length of the ureter there are three segments that physiologically narrow: the ureteropelvic junction, the ureterovesical junction, and where the ureters cross the common iliac vessels.
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This, in effect, prevents vesicoureteric reflux during steady state and micturition ( Fig. The intramural ureter is compressed by the bladder wall passively during storage and dynamically during emptying. The ureters pierce the bladder wall obliquely (termed the ureterovesical junction or UVJ and travel in this orientation for 1.5 to 2.0 cm within the bladder wall to terminate in the bladder lumen as ureteral orifices ( 4). As the ureters enter the pelvic cavity they turn medially and cross in front of the common iliac bifurcation. They originate at the ureteropelvic junction (UPJ) behind the renal artery and vein and then progress inferiorly along the anterior portion of the psoas muscle. They are generally 22–30 cm in length and course through the retroperitoneum.
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The ureters are bilateral fibromuscular tubes that drain urine from the renal pelvis to the bladder. 74.8, with permission of the publisher.) doi:10.1128/1 Normal anatomy of the kidney and upper urinary tract. We also highlight the important structural and functional abnormalities that predispose the urinary tract to microbial infections. In this chapter, we provide an overview of the basic anatomy and physiology of the urinary tract with an emphasis on their specific roles in host defense. Additionally, infections of the upper urinary tract often require hospitalization and prolonged antibiotic therapy. In fact, recurrent urinary tract infections are a significant cause of morbidity and time lost from work and a major challenge to manage clinically. When this integrity is breached, however, the urinary tract can be at a heightened risk or even recurrent episodes of microbial infections. How can the urinary tract be so effective in fending off harmful microbes despite its orifice in a close vicinity to that of the microbe-laden gastrointestinal tract? While a complete picture is still evolving, the general consensus is that the anatomical and physiological integrity of the urinary tract is of paramount importance in maintaining a healthy urinary tract. The fact that urinary tract infections are hard to elicit in experimental animals except with inoculum 3–5 orders of magnitude greater than the colony counts that define an acute urinary infection in humans (10 5 cfu/ml), also speaks to the robustness of the urinary tract defense. This is a far cry from the upper respiratory tract infections, which can afflict an otherwise healthy individual countless times. For those who do experience an initial infection, the great majority (70% to 80%) thankfully do not go on to suffer from multiple episodes. Not surprisingly, infection of the urinary tract over a healthy person’s lifetime is relatively infrequent, occurring once or twice or not at all for most people. Yet, under most normal circumstances, it is typically considered sterile, i.e., devoid of microbes, a stark contrast to the gastrointestinal and upper respiratory tracts where many commensal and pathogenic microbes call home. The urinary tract exits to a body surface area that is densely populated by a wide range of microbes.