There are two types of vesicoureteral reflux, or VUR.

输管反流（VUR）有两种类型。

Chronic vesicoureteral reflux can cause pyelonephritis, or inflammation of the kidney, and renal scarring, or fibrosis which damages the kidney tissue.

慢性输管反流可能导致肾盂肾炎，即肾脏出现炎症反应，以及瘢痕肾，即肾组织因纤维化而受损。

Risk factors include urinary tract infections, as well as vesicoureteral reflux and obstructive uropathies, both of which are also risk factors for urinary tract infections.

危险因素包括路感染，还有输管反流和路梗阻，这两也是路感染的危险因素。

Vesicoureteral reflux is usually classified by severity - grade I through V, depending on how far urine refluxes back up into the urinary tract.

输管反流根据严重程度分为1-5级，严重程度依据液反流的程度进行衡量。

Primary vesicoureteral reflux is usually due to a short ureter, while secondary vesicoureteral reflux is usually due to a blockage in the urinary tract.

原发性输管反流，多由于输管短小；而继发性输管反流，多由于路中存在阻塞。

Secondary vesicoureteral reflux is most commonly caused by recurrent urinary tract infections, which can cause inflammation in the ureters making them swell up and close.

继发性输管反流，最常见于反复的路感染；炎症反应会引起输管肿胀和闭塞。

Vesicoureteral reflux can be diagnosed with an abdominal ultrasound, which can detect blockages in flow of urine and swelling in the ureters or kidneys.

输管反流可通过腹部超声检查确诊，可检测到液流动阻塞，以及输管和肾的肿胀。

As a child grows, the ureter gets longer and the function of the valve improves, so primary vesicoureteral reflux sometimes improves or disappears over time.

随着婴幼儿的成长，输管变长，瓣膜的功能也有所改善，因此，原发性输管反流可能随时间改善，甚至消失。

The vesicoureteral orifice is the one-way valve that allows urine to flow from each ureter into the bladder, but not in the reverse direction.

输管口是一个单向通道，允许液从每个输管进入，但不可逆流。

In vesicoureteral reflux, there is some obstruction in that path which causes pressure to build up and a current of urine actually pushes backward from the bladder into the ureters and kidneys.

输管反流中，路存在阻碍，导致中压力升高，液受压从逆流至输管再到肾。

Alright, as a quick recap, vesicoureteral reflux is a condition where pressure in the urinary outflow tract increases and urine gets pushed back up into the ureters or kidneys.

得！快速复习一下：输管反流是指一种由路压力增高导致液在压力作用下逆流至输管或肾的疾病。

All right, as a quick recap: acute pyelonephritis is typically a bacterial infection of the upper urinary tract, which usually develops from a lower urinary tract infection, especially in individuals with vesicoureteral reflux.

得！快速回顾一下：急性肾盂肾炎是一种典型的上路细菌感染，通常由下路感染发展而来，尤其在输管反流患中。