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Vesicoureteral Reflux

Judith D. Laval, MD


Vesicoureteral reflux is defined as the retrograde flow of urine from the bladder into the ureter and collecting system. Children who have a urinary tract infection (UTI) have a 45% incidence of vesicoureteral reflux. The incidence increases with decreasing age, and 65% of patients are females. However, in a male who has a UTI, the risk of reflux is 30%.

Pathophysiology of Vesicoureteral Reflux

Vesicoureteral reflux may cause renal parenchymal injury, including segmental scarring, global renal atrophy, and renal growth failure.

Pregnancy may exacerbate already compromised renal function caused by reflux nephropathy.


Radiologic evaluation for vesicoureteral reflux should be undertaken when a urinary tract infection occurs in one of the following patients:

UTI in a male

UTI in an infant (under two years of age)

Pyelonephritis in a female

Recurrent UTI in a female

Radiologic evaluation of the child with a urinary tract infection consists of a renal ultrasound and a voiding cystourethrogram (VCUG). If the child is not toxic, the VCUG and renal ultrasound should be done three weeks after initiation of antibiotics for UTI. However, if the child is toxic or hospitalized, the ultrasound should be done promptly in order to exclude the presence of an obstructive uropathy, which requires prompt urological intervention.,

Grading of Vesicoureteral Reflux

Grade I reflux is defined as retrograde urine flow into a non-dilated ureter.

Grade II reflux refers to the filling of a non-dilated ureter and a non-dilated renal pelvis.

Grade III reflux consists of dilatation of the collecting system, but the fornices remain sharp.

Grade IV reflux consists of blunted fornices.

Grade V reflux is defined as massive dilatation and tortuosity of the collecting system.

Medical Management

Most cases of vesicoureteral reflux are managed nonoperatively with attention to perineal hygiene, normalization of bowel and voiding habits, and prophylactic antibiotics.

Diaper rashes and chemical irritants such as bubble bath should be discouraged because they predispose to UTIs. Children should avoid harsh soaps, shampoos, and tub baths. If constipation is a problem, stool softeners and scheduled defecation programs are effective.

Prophylactic Antibiotics

Trimethoprim/sulfamethoxazole is the most commonly used drug, given in a dose of 2mg/kg of trimethoprim plus 10mg/kg of sulfamethoxazole orally once a day before bedtime. Adverse reactions may include Stevens Johnson syndrome, allergies, and blood dyscrasias.

For the newborn, penicillin or ampicillin are preferred for prophylaxis.

Suppression continues until the reflux resolves spontaneously or until surgery is performed.

Patient Monitoring

Urine cultures are obtained for 3 months after any UTI. Thereafter, a urine culture is obtained every other month for 6 months. If the urine remains sterile, surveillance cultures are then obtained every 3 months.

Repeat imaging is obtained every 6-12 months. Follow-up can be done with a nuclear cystogram. Patients who have minimal or no scarring may only need an ultrasound.

Surgical Management

Absolute indications for ureteral reimplantation include progressive renal injury or breakthrough infections, despite urinary suppression.

Patients who have grade V vesicoureteral reflux should be managed by ureteral reimplantation. Relative indications for surgery include grade IV reflux and failure of reflux to resolve following 4 years of therapy.