ureterocele

A ureterocele is a congenital dilation of the distal ureter that forms a cyst-like sac within the bladder wall. It is most often associated with a duplex collecting system, in which an upper-pole moiety drains via an ectopic ureterocele, though ureteroceles can occur with a single ureter. Ureteroceles can be intravesical (orthotopic) when contained entirely within the bladder, or ectopic when the ureterocele extends toward or beyond the bladder neck or urethra.

Etiology and anatomy: The condition arises from abnormal development of the ureteral orifice and the Wolffian (mesonephric) duct during embryogenesis. In duplex systems, a refluxing or obstructed upper-pole ureter is common, and the ureterocele may contribute to obstruction of the urinary tract and impaired drainage of the associated renal moiety.

Clinical presentation: In infants, ureteroceles are often detected by prenatal ultrasound as hydronephrosis or a cystic bladder lesion, and postnatally by UTIs, poor urinary stream, abdominal mass, or urinary incontinence in older children. Some patients are asymptomatic and diagnosed incidentally. Complications include urinary obstruction, recurrent infections, bladder dysfunction, and reflux.

Diagnosis: Imaging typically starts with ultrasound, which may show a cystic intravesical structure. Voiding cystourethrography can assess associated vesicoureteral reflux and ureterocele visualization. Additional studies such as MRI or CT urography and cystoscopy may be used to evaluate anatomy, function, and guide management.

Management: Treatment is individualized based on anatomy and renal function. Small, nonfunctional upper poles or asymptomatic cases may be observed or managed conservatively. Endoscopic incision or unroofing of the ureterocele decompresses it; in duplex systems, lower-pole ureteral reimplantation and upper-pole nephrectomy or upper-pole heminephrectomy may be required if function is poor. Prophylactic antibiotics may be used to prevent infections.

Prognosis and follow-up: With appropriate management, many patients have good renal outcomes. Ongoing follow-up focuses on renal function, residual reflux, and surveillance for recurrent obstruction or infections.