This Month in Pediatric Urology

Article Outline

• Urological Counseling and Followup for Pediatric Tuberous Sclerosis Complex
• Pediatric Robot Assisted Retroperitoneoscopic Pyeloplasty
• Ureteroscopy as First Line Treatment for Pediatric Stone Disease
• Maximum Voided Volume in Monosymptomatic Nocturnal Enuresis
• Effects of Bladder Neck Incision on Urodynamic Abnormalities
• Copyright

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Urological Counseling and Followup for Pediatric Tuberous Sclerosis Complex 

Renal involvement is common and can pose significant management issues in adults and occasionally in children with tuberous sclerosis. The genes responsible for the condition include TSC1 and TSC2. Renal cystic involvement may resemble autosomal dominant polycystic kidney disease because the causative gene, PKD1, is 60 base pairs from TSC2. Castagnetti et al (page 2155) from Padua, Italy retrospectively reviewed their experience with 41 children with tuberous sclerosis of whom 15 (37%) had renal involvement. Median patient age at diagnosis of tuberous sclerosis was 0.6 year and median followup was 8.2 years. Renal involvement was diagnosed at a median patient age of 10.8 years. Renal lesions included angiomyolipoma (74%), simple renal cysts (13%) and large bilateral cysts (13%). Angiomyolipomas were identified in 11 children at a median age of 15.4 years. In 8 children the largest lesion was 1.4 cm, which did not require treatment, and of the remaining 3 children with bilateral lesions 2 had lesions larger than 4 cm, which were symptomatic and required treatment. Neither of the 2 simple renal cysts was symptomatic. In 2 patients with large bilateral renal cysts, consistent with polycystic kidneys, end stage renal disease developed in the second decade of life. Renal involvement was more common in those with 3 or more extrarenal manifestations of tuberous sclerosis. The authors recommend renal sonography as baseline assessment with further evaluation tailored based on genetic characteristics.

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Pediatric Robot Assisted Retroperitoneoscopic Pyeloplasty 

At most centers laparoscopic pyeloplasty is performed in children via either a transperitoneal or retroperitoneoscopic approach. In contrast, robot assisted pyeloplasty is usually performed via a transperitoneal approach. Olsen et al (page 2137) from Aarhus, Denmark retrospectively analyzed their experience with 65 children who underwent robot assisted retroperitoneoscopic pyeloplasty during the last 5 years. Most cases involved dismembered pyeloplasty and the anastomosis was performed with either 5 or 6-zero polyfilament resorbable suture. Patient age was 1.7 to 17 years (mean 7.9 years), mean operative time was 146 minutes and mean time for anastomosis in the last 37 patients was 50 minutes. One patient with massive hydronephrosis underwent conversion to an open procedure, and in 4 a nephrostomy tube was inserted postoperatively. A stent was not placed in 20% of the cases, although subsequent nephrostomy placement was necessary in 2 and 3 other patients had stent complications. At followup the success rate was 94%. The authors conclude that the retroperitoneal approach provides more direct access to the ureteropelvic junction and advocate its use in robot assisted pyeloplasty.

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Ureteroscopy as First Line Treatment for Pediatric Stone Disease 

Endoscopic management of stone disease in children has evolved during the last 2 decades due to the development of smaller and more durable instruments. Smaldone et al (page 2128) from Pittsburgh, Pennsylvania retrospectively analyzed their experience with 100 consecutive children who underwent 115 ureteroscopic procedures for treatment of renal or ureteral calculi between 2001 and 2005. The procedure was performed with either a 6.9Fr flexible or 7.5Fr semirigid ureteroscope. Ureteral orifice dilation was used with 8/10Fr ureteral dilators if the ureter had not been stented. Ureteral access sheaths (internal diameter 9.5 or 12Fr) were used to facilitate flexible ureteroscopy in patients with large proximal ureteral or renal pelvic stone burdens. An indwelling stent was left postoperatively in 76% of the cases and was usually removed within a week. Ureteroscopy became first line therapy in this series, accounting for 73% of the procedures. Mean patient age was 13 years and mean stone size was 8.3 mm. Calculi were removed with a basket or fragmented with the holmium:YAG laser. A ureteral stent was placed in 5 patients because of intraoperative ureteral perforation or extravasation, and in 1 patient a distal ureteral stone necessitated ureteroneocystostomy. At followup the stone-free rate was 91%, based on sonography, radiographs or computerized tomography. The authors advocate ureteroscopy as first line treatment of ureteral and renal pelvic stones in children.

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Maximum Voided Volume in Monosymptomatic Nocturnal Enuresis 

Holding exercises and/or oxybutynin chloride often is prescribed for children with monosymptomatic nocturnal enuresis. Van Hoeck et al (page 2132) from Antwerp, Belgium performed a prospective trial in which children with nocturnal enuresis were randomly allocated to holding exercises with placebo or oxybutynin, placebo alone, oxybutynin alone or alarm therapy (control) for 12 weeks. Maximum voided volume (MVV), holding exercise volume and response to treatment were the primary outcome measures. MVV increased 21% with holding exercises plus placebo and 41% with holding exercises plus oxybutynin. Medication or placebo alone without holding exercises did not increase MVV, nor did alarm therapy. When frequency of nocturnal enuresis was assessed, the therapeutic effect was minimal in the 4 treatment groups, whereas the alarm group had a 73% response rate (meaning 0 or 1 wet night in 28 cases). The authors conclude that holding exercises increase MVV significantly but they have no effect on nocturnal enuresis.

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Effects of Bladder Neck Incision on Urodynamic Abnormalities 

Voiding dysfunction is common after valve ablation in boys with posterior urethral valves (PUV). Kajbafzadeh et al (page 2142) from Tehran, Iran performed a prospective study in which boys with PUV were treated with conventional transurethral ablation of the valves plus bladder neck incision or transurethral ablation alone. The patients were not randomized. Based on parental preference, 22 boys underwent the combined procedure and 50 valve ablation only. A cohort of the latter group was used to compare the 2 treatment modalities. Mean patient age at treatment was 1.6 years. At followup none of the boys treated with the combined procedure had bladder hypercontractility, whereas 37% treated with valve ablation alone had hypercontractility and a higher mean maximum detrusor pressure. The authors propose that a combined bladder neck incision and valve ablation procedure may yield better urodynamic parameters in boys with PUV compared to valve ablation alone. However, further studies are necessary to evaluate this concept.