Vesicoureteral reflux, or “reflux” as it is commonly known, refers to the condition where urine travels backward from the bladder up to the kidneys. Often this is first diagnosed in children after a bladder infection associated with a high fever. It is also diagnosed on occasion in newborn children noted to have an abnormal appearance to their kidneys or bladder on prenatal ultrasound. Reflux is due to two possible causes: an abnormality in the way in which the ureters (tubes which connect the kidneys to the bladder) connect to the bladder, or irregular bladder function, which results in abnormally high bladder pressures. (sometimes associated with neurologic issues). Reflux itself is not harmful to the kidneys, but it does place patients at an increased risk for kidney infections. In some circumstances, children may need surgery to correct reflux. Fortunately, in many cases, with careful treatment of any underlying bladder issues, patient growth, and potty training in those patients diagnosed with reflux before the age of potty training, surgery is not necessary, and reflux will resolve on its own.