Effects of sterile high pressure vesicoureteral reflux on the monkey.

We surgically produced high-grade sterile vesicoureteral reflux in infant monkeys by unroofing the intravesical ureter and partially ligating the bladder neck. Half of the monkeys developed a decrease in renal function and were found to have interstitial nephritis. We found that this was due to a high resting bladder pressure, which affected the function and structure of the ureter. Thus, when a functional obstruction occurs in the refluxing ureter, renal function may be lost even when the urine is sterile. This situation is like that occurring in the patient with posterior urethral valves.