Extracorporeal shock-wave lithotripsy for treatment of ureteral calculi in paediatric patients

Minimally invasive approaches and their efficacy in pediatric urolithiasis

OBJECTIVE

We compared the frequency of usage and success of minimally invasive approaches in the management of pediatric urolithiasis in our clinic.

MATERIAL AND METHODS

Data from pediatric patients (≤16 years of age) who had undergone percutaneous nephrolithotomy (PNL), ureterorenoscopy (URS), and extracorporeal shock wave lithotripsy (ESWL) between January 2001 and December 2011 were retrospectively investigated.

RESULTS

In this study, 415 pediatric patients, who were treated for 291 renal, and 124 ureteral stones, were evaluated. The patients were treated with PNL (n=148; 82 boys, 66 girls), URS (n=99; 58 boys, and 41 girls) or ESWL (n=168; 91 boys, and 77 girls). The mean patient ages were 7.3 (1-16), 9.1 (1-16), and 8.8 (1-16) years in the PNL, URS, and ESWL groups, respectively. The stone-free rates after treatment with PNL, URS, and ESWL were 77, 83.8 and 88.7%, respectively.

CONCLUSION

It is important that selected therapies are properly planned, and the use of minimally invasive approaches is important in pediatric patients due to potentially high recurrence rates. Currently, ESWL, PNL and URS are performed with high success rates for the treatment of stones, and open surgery is rarely used due to the success obtained with minimally invasive approaches.

Pediatric urolithiasis: the current surgical management

Children represent about 1% of all patients with urolithiasis, but 100% of these children are considered high risk for recurrent stone formation, and it is crucial for them to receive a therapy that will render them stone free. In addition, a metabolic workup is necessary to ensure a tailored metaphylaxis to prevent or delay recurrence. The appropriate therapy depends on localization, size, and composition of the calculus, as well as on the anatomy of the urinary tract. In specialized centers, the whole range of extracorporeal shock-wave lithotripsy (ESWL), ureterorenoscopy (URS), and percutaneous nephrolithotomy (PCNL) are available for children, with the same efficiency and safety as in adults.

Shock wave lithotripsy is effective and safe for distal ureteral calculi in children

We evaluated the effectiveness of the Siemens Lithostar Modularis lithotriptor for the management of distal ureteric calculi in children. Between 2004 and 2006, 29 children with distal ureteric calculi were treated in our stone center with the Siemens Lithostar Modularis (Siemens Medical Solutions, Inc.) Effectiveness of lithotripsy, retreatment and efficacy quotient rates, and complications were assessed. The series consisted of 18 (62%) boys and 11 (38%) girls with an age range of 1-13 years (average age 7.0 +/- 3.5). Under fluoroscopic guidance, children were treated with a maximum 3,000 shocks at an average of 2.2 +/- 0.3 kV. Mean stone size was 8.2 +/- 3.2 mm (range 4-18). Success was defined as the lack of any visible stone fragments on posttreatment radiological evaluation. The mean number of sessions required was 1.5 +/- 0.8/patient (range 1-4). Complete clearance rate at 3 months was 86.2%. Re-treatment and efficacy quotient rates for distal ureteral stones were 41.4 and 55.6%, respectively. Complications such as urinary tract infection or steinstrasse occurred in 2 (6.9%) patients. Minor complications included petechial skin hemorrhage at the site of entry of shock waves in all patients. Our results show that shock wave lithotripsy for distal ureteral calculi with the Siemens Lithostar Modularis lithotriptor has a high success rate (86.2%) and efficacy quotient (55.6%) with negligible complications in children.

Management of pediatric stone disease

Pediatric and adult stone disease differs in both presentation and treatment. Children can present with a wide range of symptoms varying from flank pain and hematuria to nonspecific symptoms such as irritability and nausea. Although ultrasonography and plain radiographs can play a role in diagnosis and follow-up, the standard of care for a child who presents to the emergency department with a history suggestive of a stone is noncontrast spiral CT. Because there is a high yield in identifying predisposing factors in children with urolithiasis and high recurrence rates, metabolic evaluation of every child with a urinary stone should be undertaken and medical treatment should be given if necessary. With recent advances in technology, stone management has changed from an open surgical approach to less invasive procedures such as extracorporeal shock-wave lithotripsy and endoscopic techniques. Herein, we present a review of the recent literature and offer our own preferences to approaches for treatment.