A ureterocele can affect one ureter (unilateral ureterocele) or both ureters (bilateral ureterocele). A unilateral ureterocele is the more common type. Healthcare providers can also classify a ureterocele depending on its location.

Happen on both sides, from both kidneys (bilateral ureterocele). Ureteroceles are most often found in children age two or younger. Sometimes it is found older children or adults.

Ureteroceles can be associated with a single system (one kidney and one ureter) or a duplex kidney (one kidney with two separate ureters). Ureteroceles can be associated with vesicoureteral reflux (VUR). VUR occurs when urine in the bladder flows back into one or both ureters and often back into the kidneys. Testing and diagnosis

About 10% of all ureteroceles are bilateral, potentially affecting both renal units. Among these bilateral cases, approximately 80% are associated with completely duplicated urinary systems; each kidney has 2 separate ureters. The remaining 20% of ureteroceles are sporadic anomalies without an associated duplicated urinary system.

Bilateral ureteroceles are seen in 10% of cases only 10. Most ureteroceles are congenital, usually associated with the ectopic insertion of the ureter with associated duplicated collecting system (see below). In a minority of cases, ureteroceles are an isolated abnormality, and these are usually seen in adults (see below). Pathology