In utero treatment of obstructing ureterocele

PURPOSE: To describe our recent experience with an obstructing submucosa! ureterocele which poses both a diagnostic and therapeutic dilemma, but which may now be amenable to in utero therapy. STUDY DESIGN: A 32 y/o G2P1 was referred at 19.5 wks with decreased AFV, bilateral hydronephrosis/hydroureters, and presumed enlarged bladder with dilated proximal urethra. Color doppler-assisted high resolution ultrasound demonstrated a mildly enlarged, abnormally shaped bladder (previously diagnosed as a dilated urethra) and a large posterior cystic structure. This was consistent with a Rt. submucosal ureterocele which distorted the back of the bladder catising contralateral u re te rove sic al obstruction and hydronephrosis/ureter. Sequential drainage and urinalysis showed rapid recurrence, and worsening renal function. At 22 wks, in utrm cystoscopy identified an ectopic coniform insertion of the Rt. ureter and characteristic mucosal window. This was treated in utero as it is postnatally by incision drainage, resulting in resolution of bladder distortion and Lt. hydronephrosis. One week later the ureterocele had recurred. A Rocket shunt was placed through the fetal bladder into the ureterocele resulting in complete drainage and resolution of contralateral ureterovesical obstruction. Shunt was displaced into the amniotic space at 30 wks. RESULTS: A male infant was delivered at 36 wks with Rt. megaureter and nonfunctional kidney, Lt grade V reflux, and hypospadius. At 4 months he underwent Rt. uretero-nephrectomy and Lt. ureteral reimplantation. The Rl. ureter had ectopic insertion into the posterior proximal tirethra at the bladder neck. Pathologic evaluation showed Rt. renal fibrodysplasia, partial duplication of the upper Rt. ureter and a lower megaureter with valve-like structures. At 1 year of age, the infant has a serum crcatinine of 0.4 mg/dl, and stable Lt. hydronephrosis. CONCLUSION: Submucosal ureteroceles can be difficult to diagnose and may be confused with proximal urethra! obstructions. They may cause contralateral ureteral obstruction associated with hydronephrosis and progressive renal damage. Careful prenatal evaluation and patient selection for treatment with diverting shunt therapy may preserve contralateral renal function in such cases.