Vesicoureteral reflux (VUR) is the medical term for urine flowing back (reflux) from the bladder (vesico) to the kidneys via the ureters (ureteral). VUR occurs when the pressure in the bladder is high and there is something stopping the urine from flowing out through the urethra. This may be due to a blockage in a catheter but could be because the sphincters are too tight.
Normally there is a valve between the bladder and the ureters that stops the urine flowing back up to the kidneys. If there is too much pressure these valves can fail.
Signs and symptoms of a VUR
You may get flank pain, recurrent pyelonephritis (kidney infections) or have abnormal kidney function on blood tests. Very rarely, VUR can present with kidney failure in a patient who has not managed their bladder very well.
VUR can usually be detected easily by an ultrasound scan of the kidneys. If VUR is present, the scan will show hydronephrosis or kidney swelling. Occasionally some patients who have not seen their doctor in a while may develop VUR if their bladder management is not adequate.