Pediatric urolithiasis: review of research and current management

Extracorporeal shock wave lithotripsy in children: Results and short-term complications

AIM

The introduction of extracorporeal shock wave lithotripsy represented an important evolution in urinary tract lithiasis management. The aim of this study is to describe the results of extracorporeal shock wave lithotripsy for the treatment of urinary tract lithiasis in children, focusing on the index of elimination of the calculi and the complications occurring during the procedure and during the following three months.

METHODS

From September 1991 to July 2002, 135 children between one and 12 years, suffering from urinary tract lithiasis underwent extracorporeal shock wave lithotripsy. A retrospective analysis of these patients was carried out.

RESULTS

One hundred and ninety-five calculi ranging in size from 5.0 mm to 20.0 mm were treated, out of which 147 were found in the kidneys and 48 in the ureter. Urinary tract dilation was presented by 30% of the children at the time of the procedure. After extracorporeal shock wave lithotripsy 75.8% of the calculi were eliminated: 64.1% were stone-free and 11.7% had < or = 4 mm stones. Ureteral calculi and 5-10 mm stones responded better than the kidney and 11-20 mm stones (P = 0.027 and P = 0.012, respectively). No differences were detected according to the calculi location, whether in the ureter or kidney (P = 0.637 and P = 0.703, respectively). The shock wave intensity of 14kv was as efficient as the higher voltage. Short-term complications were observed in 23.7%, characterized by fever and pain.

CONCLUSION

In children, extracorporeal shock wave lithotripsy proved to be able to eliminate 75.8% of the treated calculi and 83.7% of the patients presented a complete or partial response. Complications were observed in 23.7% of patients, and pain was the most frequent symptom.

Extracorporeal shock wave lithotripsy in the management of pediatric urolithiasis

The main objective of this paper was to evaluate the efficacy and safety of the management of pediatric urolithiasis by extracorporeal shock wave lithotripsy (ESWL). Between November 1988 and July 2000, 165 renal stones, 53 ureteral stones, and 5 bladder stones were treated in 126 pediatric patients using Siemens Lithostar lithotriptor. The ESWL treatments ranging from 1 to 7 were needed per patient (mean: 2.1). One ESWL session was performed for 49.6% of stones, two for 24.6%, three for 13.0 %, four for 5.6% and > 4 for 8.2%. The success rate for renal stone units (asymptomatic fragments less than 4 mm) was 88.2%, stone-free rate was 49.0%. The stone-free rate for ureteral stone units was 87.5%, but was 75% for bladder stones. The overall results of ESWL treatment in 126 children was satisfactory: the success rate was 90.5%, stone-free rate was 51.6%, residual fragments > 4 mm were 9.5%. General anesthesia was required in 65 children (136 treatments) under the age of 10, and only in 18 children (40 treatments) in the age 11-14. Auxiliary procedures, such as double J stent and percutaneous nephrostomy (PCN) were used in 19 and 7 patients, respectively. Perirenal hematoma in one patient and hematomas in enteric wall in another one patient were the only major complications managed conservatively without consequences. Low energy lithotripsy with the Siemens Lithostar in our series of pediatric patients was safe and relatively effective.

Strategies for managing upper tract calculi in young children

PURPOSE

Pediatric urolithiasis is relatively uncommon and there is little information on the application of modern surgical procedures in young children. We present a single center experience with the surgical management of upper tract calculi in this age group.

MATERIALS AND METHODS

We reviewed presentation, co-morbidity, treatment, outcome and complications in all prepubertal patients who required surgical treatment for ureteral or renal calculi during a 4-year period. The series consists of 24 girls and 17 boys 17 months to 14 years old (mean age 7.5 years). A total of 26 children were anatomically normal, and 4 had myelomeningocele, 4 had ureteropelvic junction obstruction (in a pelvic kidney in 1), 2 had cloacal anomalies, 2 had vesicoureteral reflux, and 1 each had nonrefluxing megaureter, orthotopic ureterocele and a functioning renal transplant.

RESULTS

Extracorporeal shock wave lithotripsy was performed in 24 patients. Stents or nephrostomy tubes were only used in the 4 patients who presented with pyonephrosis. Of the 41 cases 17 were rendered stone-free, 3 had a decreased stone burden and 4 were failures. Ureteroscopic extraction of distal ureteral calculi was successful in 11 of 12 children, of whom the youngest was 2.5 years old. No child had postoperative infection or evidence of ureteral obstruction. Stent placement facilitated stone passage or dissolution in 2 patients, a renal calculus was percutaneously extracted in 2 and 7 required open surgery, mostly for correcting simultaneous anatomical abnormalities or after minimally invasive surgery failed. Some metabolic abnormality was detected in 80% of the children tested.

CONCLUSIONS

The surgical management of upper urinary tract calculi in young children parallels that in adults. Minimally invasive surgical methods may be safely used even in young infants. Most children do not need elective stenting before lithotripsy. Open procedures are still required in 17% of cases. The majority of children have definable metabolic abnormalities.

Strategies for managing upper tract calculi in young children

PURPOSE

Pediatric urolithiasis is relatively uncommon and there is little information on the application of modern surgical procedures in young children. We present a single center experience with the surgical management of upper tract calculi in this age group.

MATERIALS AND METHODS

We reviewed presentation, co-morbidity, treatment, outcome and complications in all prepubertal patients who required surgical treatment for ureteral or renal calculi during a 4-year period. The series consists of 24 girls and 17 boys 17 months to 14 years old (mean age 7.5 years). A total of 26 children were anatomically normal, and 4 had myelomeningocele, 4 had ureteropelvic junction obstruction (in a pelvic kidney in 1), 2 had cloacal anomalies, 2 had vesicoureteral reflux, and 1 each had nonrefluxing megaureter, orthotopic ureterocele and a functioning renal transplant.

RESULTS

Extracorporeal shock wave lithotripsy was performed in 24 patients. Stents or nephrostomy tubes were only used in the 4 patients who presented with pyonephrosis. Of the 41 cases 17 were rendered stone-free, 3 had a decreased stone burden and 4 were failures. Ureteroscopic extraction of distal ureteral calculi was successful in 11 of 12 children, of whom the youngest was 2.5 years old. No child had postoperative infection or evidence of ureteral obstruction. Stent placement facilitated stone passage or dissolution in 2 patients, a renal calculus was percutaneously extracted in 2 and 7 required open surgery, mostly for correcting simultaneous anatomical abnormalities or after minimally invasive surgery failed. Some metabolic abnormality was detected in 80% of the children tested.

CONCLUSIONS

The surgical management of upper urinary tract calculi in young children parallels that in adults. Minimally invasive surgical methods may be safely used even in young infants. Most children do not need elective stenting before lithotripsy. Open procedures are still required in 17% of cases. The majority of children have definable metabolic abnormalities.

Treatment update on pediatric urolithiasis

At the doorstep of the twenty-first century the role of extracorporeal shock-wave lithotripsy (ESWL) as the treatment of choice for more than 80% of all stones in children is established. ESWL is safe and effective, with very few differences in success rates being observed among different lithotriptors. The present problem with ESWL appears to be the residual stone fragment, which has a proven clinical significance. A thorough metabolic evaluation and metaphylaxis is indicated in all children, and this will enable physicians to deal with the residual fragments in a more cause-specific manner and prevent regrowth. Another subject that needs prospective randomized studies to be unveiled is the assumption that a specific or universal metaphylaxis, possibly with alkaline citrates, will enhance stone clearance, lower the incidence of residual stone fragments, and optimize the ESWL results. Finally, both percutaneous nephrolithotomy and ureteroscopic stone removal have been established in children as safe and effective treatment options. This gives the clinician the opportunity to choose from a wide range of treatment alternatives, including open surgery, and only this approach will ensure 100% stone removal in individual patients along with the prevention of recurrence and, thus, the elimination of long-term morbidities in this vulnerable patient population.

Glycosaminoglycans, proteins, and stone formation: adult themes and child's play

The relative infrequency of renal stones in children is probably the main reason for the paucity of literature devoted to the study of urolithiasis in pediatric patients. Nonetheless, when pediatricians do address the issue, the contents of their papers reflect those prevalent in the adult literature; with one notable exception. Papers dealing with the potential role of urinary macromolecules in pediatric stone disease are very scarce indeed; to my knowledge, only four have been published in the English literature in the last 15 years. One of these is to be found in this issue and, like the remaining three, it compares the urinary excretion of glycosaminoglycans in healthy children and those with stones. This article briefly reviews the history of the association of urinary macromolecules, particularly glycosaminoglycans and proteins, with calcium oxalate urolithiasis, and discusses in more detail the published experimental evidence for their fulfilling a determinant role in stone formation.