This Month in Pediatric Urology

Article Outline

• Urinary Incontinence and Distal Penile Epispadias
• Pediatric Flexible Ureteroscopic Lithotripsy
• Donor Site Outcome After Oral Mucosal Harvest for Urethroplasty
• Urinary Tract Infections in Patients with Bladder Augmentation and Kidney Transplant
• Copyright

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Urinary Incontinence and Distal Penile Epispadias 

Epispadias, independent of exstrophy, is a complex congenital malformation covering a wide spectrum of anatomical and physiological deficiencies. It is not surprising that proximal epispadias extending into a deep peno-pubic location will be associated with deficiencies of the external urinary sphincter and bladder neck resulting in incontinence. Interestingly, distal shaft epispadias and glanular epispadias have also been associated with a higher incidence of urinary incontinence. Canon et al (page 2636) from Columbus, Ohio explore the pathophysiology in 6 boys with distal or glanular epispadias. All boys had undergone a single stage epispadias repair and were incontinent after prolonged toilet training attempts had failed.

Cystoscopy and urodynamic testing were performed to better understand the pathophysiology. Cystoscopic findings revealed a deformity in the roof and interior side walls of the bladder neck and posterior urethra. This defect extended distally through the membranous sphincter and into the penile urethra. This defect was repaired in 5 of the 6 boys using a simplified bladder neck reconstruction (SBNR) technique. Histological examination of the excised defective tissue revealed abnormal architecture with severe attenuation and reduction of smooth muscle fibers. Daytime continence and normal urinary control were achieved in all 5 boys. Postoperative voiding cystourethrogram showed normal narrowing of the bladder neck, prostatic and proximal urethral regions.

The authors conclude that the pathophysiological defect of distal epispadias is not isolated to the visible abnormality but is associated with a field defect of abnormal tissue deficient in smooth muscle and elastic elements, particularly affecting the roof of the urethra and extending through the bladder neck. A physiological bladder neck and sphincter mechanism can be created with SBNR.

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Pediatric Flexible Ureteroscopic Lithotripsy 

Minimally invasive techniques continue to evolve in the management of pediatric stone disease. Current modalities of shock wave lithotripsy, percutaneous nephrolithotomy and ureteroscopic management vie for superiority in the treatment of upper tract pediatric stones. Kim et al (page 2616) from Philadelphia, Pennsylvania identified 170 ureteroscopic procedures performed during a 3-year period after a trial of conservative management failed in 167 children with a mean age of 62.4 months. The majority of the stones were above the ureteropelvic junction in the lower pole of the kidney and the others were in the ureter above the iliac vessels. Ureteroscopy could not be performed initially in 95 children and so a ureteral stent was placed for passive dilation. There was no statistical difference between the 2 ureteroscopes used in these cases in regard to the ability to gain retrograde access. Ureteral access sheath were used at the discretion of the operating surgeon only in children with a previous stent and based on stone burden. The calculi were fragmented with a holmium:YAG laser and retrieved by basket extraction. Postoperative ureteral stents were used depending on the difficulty and complexity of the procedure, and the stent length rule of “years of age plus 10” was accurate in 94% of patients. Stone clearance was assessed intraoperatively and with postoperative imaging.

Clearance after a single procedure was 100% for stones smaller than 10 mm and 97.5% when the stone was larger than 10 mm. A second ureteroscopic procedure rendered 100% clearance in all cases. Operative time for flexible ureteroscopy averaged 107 minutes. Intraoperative and postoperative complications were not observed. The authors provide a compelling case for flexible ureteroscopy with or without passive dilation of the ureter. They conclude the pediatric flexible ureteroscopy is highly efficacious and safe. It has become their initial form of intervention for proximal ureteral and renal stones.

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Donor Site Outcome After Oral Mucosal Harvest for Urethroplasty 

An oral mucosal graft (OMG) is an effective source of tissue for urethral reconstruction in cases of severe hypospadias and urethral stricture disease. Although the technique has been well described, data are limited regarding short and long-term complications at the donor site. Castagnetti et al (page 2624) from Padua, Italy assess the effect of oral mucosa harvesting on resuming a normal oral diet, perioral sensory deficits and impairment of jaw opening within 4 weeks of surgery and again at least 1 year postoperatively. They retrospectively reviewed the records of 169 patients who underwent OMG urethroplasty between 1994 and 2006, including 78 followed for longer than 1 year. The OMG was harvested either from the buccal (cheek) mucosa or lower lip (labial). All graft sites had been infiltrated with 1 to 100,000 epinephrine and bupivacaine to facilitate the dissection, avoid the muscles and minimize the amount of fat taken with the graft. The labial graft site was left open and the buccal site was reapproximated with polyglactin sutures. An ice pack was placed for 6 hours immediately after surgery.

Short-term complications included bleeding primarily when harvesting labial tissue in 16 (20%) cases, which was self-limited and required no transfusions. A normal diet was achieved within 3 days of surgery by 66% of the patients. All patients reported a transitory sensory deficit and 20% had mild impairment of jaw opening within the first month. Donor site scarring occurred in 42 (54%) cases, the majority of which was in the lower lip. Scarring was considered severe in 2 cases but did not cause distortion to the contour of the lip. Long-term followup revealed oral scarring as thickening of the mucosa but this did not appear to cause any serious limitation. Persistent perioral sensory impairment was reported but no patient thought the deficit was bothersome enough to require treatment. The sensory deficit occurred more commonly in the older age group. The authors conclude that OMG harvesting is safe and effective in all ages with a rapid return to diet and minimal limitations in long-term sensory deficit.

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Urinary Tract Infections in Patients with Bladder Augmentation and Kidney Transplant 

Enterocystoplasty has an important role in the management of severely hostile bladders due to neurogenic and nonneurogenic causes. Bladder hostility can result in renal failure and subsequent renal transplantation. Transplantation is successful following enterocystoplasty but there is limited information regarding an increased risk of renal demise due to bacteruria, particularly in the face of immunosuppression. Alcântara Pereira et al (page 2607) from São Paulo, Brazil review their 4-year experience with augmentation cystoplasty in 23 renal transplant patients in a comparison study with 42 controls matched for gender, age, race, donor type, weight and immunosuppression protocol. The donor type, cadaveric ischemia time and rate of acute tubular necrosis were similar in both groups. Bowel was used for augmentation in 20 patients and ureter in 3. Intermittent catheterization was performed in 16 of the 23 patients, and all performed catheterization through a continent stoma. All patients and controls received post-transplant prophylactic antibiotics consisting of trimethoprim-sulfamethoxazole for 6 months. Symptomatic urinary infections were associated with a bacterial colony count greater than 10⁴ colony forming units per ml and associated with symptoms. Asymptomatic bacteriuria was defined as a colony count greater than 10⁵ colony forming units per ml. Urinalysis and urine cultures were obtained monthly. All positive urine cultures were treated before 6 months and only symptomatic infections were treated after 6 months following transplantation.

The incidence of acute rejection within the first 12 months was 26% in the augmented group and 9% in the control group. During the first 12 months symptomatic and asymptomatic urinary infections occurred more often in the augmented group (83%) compared to the control group (17%). Infections were symptomatic in 4 of 19 patients and in 4 of 7 controls with a positive urine culture. Rehospitalization was necessary in 61% of patients and 29% of controls. While a statistically significant higher incidence of urinary infections occurred in the augmented group there was no significant difference in graft function at 6 or 12 months following transplantation. These findings are counter to previous reports indicating that urinary infections decrease graft function and graft survival. The authors conclude that symptomatic and asymptomatic bacteriuria occur more often in the augmented transplanted bladder but the overall effect on graft function and graft survival is not affected.