Stone size is the sole factor in determining the outcome of eswl in children

PurposeWe prospectively evaluated the role of stone location and size in the efficacy of SWL for the treatment of urinary calculi in children.Material and methodsBetween January 2006 and March 2007, 94 pediatric patients (108 renoureteral units) were treated by Siemens Lithostar under sedo-analgesia. There were 58 boys and 36 girls, with a mean-age of 57.4 (8- 180) months. The stones were localized in the renal pelvis, lower, middle, upper calices and ureteropelvic junction in 24, 30, 17, 7 and 10 renal units. 14 renal units had stones in multiple locations. Four patients had proximal and 2 had distal ureteral calculi. Stone free rates and efficiency quotients were assessed 3 months after SWL.ResultsThe mean stone burden was 74.6mm2 (20-380). Sixtysix (61.1%) renal units were stone-free within 12 weeks after an average of 1.48 (1-4) SWL sessions. Stone-free rates for pelvis, lower, middle, upper pole, ureteropelvic junction, upper and lower ureter were 83.3 %, 43,%, 52.9%, 71.4%, 60%, 100% and 50% respectively. Efficiency quotients for stones <5mm, 6-10 mm, 11-15 mm and 16-20mm were 0.62, 0.42, 0.53, 0.27 respectively with an overall 0.44.ConclusionsOur results indicated SWL in the treatment of pediatric urolithiasis has acceptable stone-free rates with lower efficiency quotients, the latter compensated by the minimally invasive nature of this treatment modality. Stone-size seems to be the only factor affecting the efficiency.     

Experience of percutaneous nephrolithotomy using adult-size instruments in children less than 5 years old

ObjectiveWe present our experience with percutaneous nephrolithotomy (PCNL) for management of large renal calculi in children less than 5 years old, and determine its safety and efficacy when using an adult-size device.Patients and methodsTwenty patients younger than 5 years old underwent PCNL between August 2003 and July 2008. After retrograde catheterization, the nephrostomy tract dilated up to 26 Fr. Then a 24-Fr rigid nephroscope was used and stones were fragmented with a pneumatic lithotripter.ResultsTwenty patients with a mean age of 3.1 years underwent 26 PCNL procedures on 24 renal units. Four patients had bilateral renal stones. Five patients (20%) had staghorn stones, as did five of the other cases with multiple stones. Four patients had undergone previous stone surgery on the same side. All of the patients were managed with only one tract. The mean stone size was 33 (20–46) mm and average operative time was 93.25 (78–174) min. Stones were completely cleared in 79.16% of patients, which increased to 91.67% with adjunctive shockwave lithotripsy. The overall complication rate was 15.38% and mean hospital stay was 5.26 (3–8) days.ConclusionPCNL is an effective and safe treatment for renal calculi in children less than 5 years old, even when using instruments designed for adults.     

An association between kidney stone composition and urinary metabolic disturbances in children

ObjectiveTo determine kidney stone composition in children and to correlate stone fractions with urinary pH and metabolic urinary risk factors.Patients and methodsWe studied 135 pediatric patients with upper urinary tract lithiasis in whom excreted or extracted stones were available for analyses. Composition of stones was analyzed. A 24-hour urine assessment included volume, pH and daily excretions of calcium, oxalate, uric acid, cystine, creatinine, phosphate, magnesium and citrate.ResultsCalcium oxalate was the major component of 73% stones, followed by struvite (13%) and calcium phosphate (9%). Uric acid was present in almost half of stones, but in rudimentary amounts. The calcium oxalate content in calculi showed a strong relationship with calciuria, and moderate association with oxaluria, magnesuria and acidification of urine. The percent content of struvite presented reverse and lower correlations with regard to the above parameters. Calcium phosphate stone proportion had low associations with urinary risk factors.ConclusionsCalciuria, oxaluria, magnesuria and low urine pH exerted the biggest influence on calcium oxalate content in pediatric renal stones. Relationships of urinary risk factors with calculi calcium phosphate content were of unclear significance. Urinary citrate excretion did not significantly correlate with kidney stone composition in children.     

Comparison of Pediatric Stone-Formers with and without mutations in Soluable Adenylate Cyclase

PurposeTwo-thirds of children with urolithiasis have hypercalciuria. Recently, a candidate gene for absorptive hypercalciuria (AH) was mapped to chromosome 1q23.3-24 in the adult population. In adults, the presence of up to 6 identified base substitutions in the soluble adenylate cyclase gene (sAC) was associated with a 2.2- to 3.5-fold increased risk for AH. We screened a pediatric population of stone formers for sAC sequence variations.Material and MethodsPediatric patients with stone disease were offered study participation if they met the following criteria: family history of stones; hypercalciuria (urine calcium/creatinine ratio > 0.21 mg/mg creatinine or 24 hour calcium excretion > 4 mg/kg/day); and/or calcium stones on stone analysis. Serum laboratories, spot and 24-hour urine, and bone mineral density (BMD) were collected. Patients were excluded for metabolic conditions predisposing to stone disease. Probands were genotyped for 6 previously identified base substitutions in the sAC gene. Comparisons were made between probands with and without sAC substitutions using Fisher's exact test.ResultsOf 46 children recruited, sAC substitutions were identified in 19 (41%). Clinical parameters were similar in patients with and without substitutions: positive family history in 14/17 (82%) vs. 21/27 (78%); hypercalciuria in 13/19 (68%) vs. 22/27 (82%); and mean number of stone events 2.1 vs. 2.8. Overall, 5/16 (31%) had abnormal BMD (age-adjusted Z-scores < -1.5). More patients with base substitution(s) had abnormal BMD scores (4/9, 44%, vs. 1/7, 14%, p = 0.31), tending towards lower Z-scores (-1.26 vs. -0.3).ConclusionsOf 46 pediatric stone formers, 31% had abnormal BMD scores, and 41% of probands had sAC gene base changes previously identified in adults to increase risk for stones and osteoporosis. This warrants further investigation for potential genetic screening and therapeutic interventions to prevent pediatric stone formation and long-term osteoporotic risk.     

微创经皮肾穿刺取石治疗儿童复杂肾结石

目的 探讨微创经皮肾穿刺取石治疗儿童复杂肾结石的疗效和安全性.方法 回顾性分析我院收治儿童复杂肾结石33例,男21例,女12例,年龄5～14岁,平均8.5岁.结石位于右侧16例,左侧13例,双侧4例.结石单发11例,多发19例,铸形结石3例,结石大小2.1 cm×3.2 cm-3.7 cmx6.7 cm.均采用B超定位经皮肾气压道碎石系统治疗,并观察结石清除情况.结果 本组33例均经一次穿刺即成功建立通道,其中4例行两通道碎石,4例同时行双侧碎石.31例I期行经皮肾微创造瘘术(MPCNL),2例Ⅱ期.手术时间80～130 min,平均92 min,术中出血30-80 ml,平均(61.5±12.3)ml,均无输血.1例有较大结石残留辅以体外震波碎石治疗.Ⅰ期结石清除率90.9%(30/33),Ⅱ期碎石后总清除率为96.9%(32/33).无气胸、腹腔脏器损伤、大出血等严重并发症.术后发热4例.术后24 h血红蛋白及血肌酐值与术前相比差异无统计学意义.术后住院时间4～8 d,平均5.4 d.术后随访3～18个月,平均9个月,结石无复发.结论 微创经皮肾取石治疗儿童复杂肾结石安全可行,疗效确切,具有创伤小、恢复快等优点,可成为本病首选治疗.     

Management of obstructive calcular anuria with acute renal failure in children less than 4 years in age: A protocol for initial urinary drainage in relation to planned definitive stone management

ObjectivesTo describe and evaluate our protocol for management of children ≤4years old with obstructive calcular anuria (OCA) and acute renal failure (ARF) to improve selection of initial urinary drainage (ID) method and to facilitate subsequent definitive stone management (DSM) as studies discussing this special group of patients are still few.Patients and methodsPatients with a contraindication to any method of ID were excluded. Decision (percutaneous nephrostomy (PCN) or double J (JJ) stent) was based on degree of hydronephrosis and planned DSM. We used 4.8–5Fr JJ or 6–8Fr PCN under general anesthesia and fluoroscopic guidance. According to our protocol, JJ is inserted for hydronephrosis ≤ grade 1. When the hydronephrosis is >grade 1, patients with radiolucent stones were treated by JJ whatever the site of the stone. When the stones were radiopaque, PCN was reserved for stones in a solitary functioning kidney and bilateral ureteric stones prepared for subsequent bilateral ureterolithotomy (or stone prepared for ureterolithotomy in a solitary kidney). After normalization of renal functions, DSM was staged attacking only one side before discharge. Both sides were cleared at the same session in cases with bilateral ureterolithotomy. Renal or ureteric stones suitable for SWL in a solitary kidney were treated with percutaneous nephrolithotripsy (PNL) or ureteroscopy. This was followed also in patients with bilateral stones suitable for SWL by clearing one side using ureteroscopy or PNL before discharge. Open surgery (OS) was reserved for cases with failed ureteroscopy or PNL, for ureteric stones >2.5 cm in size or very large volume complex renal stones. Stone free rate (SFR) was evaluated by CT. Our protocol was evaluated as regard recovery of renal functions, complications, and number of interventions to clear stones.ResultsThis study included 62 boys and 22 girls presented with anuria for 1–4 days. JJ and PCN were inserted in 105 and 30 ureterorenal units (URU), respectively. Creatinine returns normal within 72 h. JJ insertion formed a part of DSM in 78/159 (49%) URU (stones prepared for extracorporeal shockwave lithotripsy or oral chemolytic dissolution therapy). PCN was the ideal tract for subsequent PNL in 11/159 (6.9%) URU. Accordingly, ID participated by 55.97% in DSM. Both operative and imaging times were slightly longer with PCN than JJ. There was no statistically significant difference in the insertion success or mean period to return to normal chemistry. Complications of both methods were mild and without any significant difference. Endourologic procedures constituted the majority of our interventions. Open surgical and endoscopic interventions for clearance of stones (including ID, treatment conversion and 2ry procedures) were done once for 25 patients, twice for 43 patients while it was needed three times for 16 patients. Total number of interventions was 149 procedures. SFR was 94%.ConclusionOur protocol ensures adequate ID with minimal complications when using our selection criteria in children ≤4 years in age with OCA and ARF. It also minimizes number of subsequent procedures to clear stones. Complications and success in insertion and drainage were equivalent in PCN and JJ groups.     

Clinical outcome of infantile renal calcification

PurposeWith popularization of prenatal ultrasonogram(US), postnatal US during the infantile period has also become popular for various reasons including fetal hydronephrosis. We investigated the clinical outcome of incidentally detected calcification on US in children younger than 1 year.Material and methodsWe retrospectively reviewed the US findings and medical records of 25 children below the age of 1 in whom renal calcification was detected on US between January 2003 and April 2007.ResultsThe mean age of subjects was 4 months and renal calcification was bilateral in 5. Of the 29 renal units showing calcification fetal hydronphrosis was detected in 12 (41.4%), high grade hydronephrosis (grade III, IV, SFU) was found in 13(44.8%) and mild hydronephrosis was noted in 16(55.1%). 9 renal units showed multiple calcification and the mean size was 5.9mm. Associated anomalies included 5 UPJOs, 3 obstructive megaureters, 1 ureteocele, 2 VUR and 2 contralateral multicystic dysplastic kidneys. The calcification was radioopaque in 17 renal units. Calcification in 19(66%) of 29 renal units showed spontaneous resolution and the mean time to spontaneous resolution was 4 months. Of the remaining 10 renal units with persistent calcification, ESWL was performed in 7 renal units, anatrophic nephrolithotomy in 1, pyelolithotomy in 1 due to an increase in stone size or UTI and ureteroscopic stone removal was done in 1 due to migrated stone into the ureter.ConclusionsSince spontaneous resolution could be observed quite frequently, expectant management with follow up U/S can be recommended for infantile calcification without symptoms.     

Percutaneous nephrolithotomy (pcnl) in paediatric stones

PurposeTo evaluate the role and outcome of percutaneous nephrolithotomy (PCNL)in the management of paediatric urolithiasis.Material and methodsWe retrospectively reviewed the records of children who underwent PCNL procedures for renal calculi from 2004 to 2007 A total of 300 children with renal calculi were treated with PCNL. Patient's age at operation ranged from 8 months to 15 years. Patients had pre-operative blood and urine analysis, ultrasonography of kidneys, ureter, bladder and X-ray IVU. A tract was made in the prone position using fluoroscopy and ultrasound. 22 to 26 Fr sheaths with 18.0, 20.5 and 24 Fr nephroscopes were used accordingly. Ultrasound and pneumatic lithoclast alone or in combination were used for stone fragmentation.Results300 PCNL procedures were performed. Stone burden ranged from 3.1 ± 3.7 cm² (simple 2.1 ± 1.5 cm², complex 5.0 ± 8.8 cm²) with stone clearance rates of 92% and 78% in simple and complex stones respectively. During the procedure mean Hb drop was 1.36 ± 0.8 gm% while 26 (14.6%) patients required blood transfusion. Intra and post operative complications included excessive bleeding, and conversion to open surgery in 8, extravasation of fluid in 11 and 5 cases with urinary sepsis.ConclusionsPercutaneous nephrolithotomy is a suitable and safe procedure in children including the pre-school age group for both simple and complex stones.     

Primary versus secondary ureteroscopy for pediatric ureteral stones

ObjectiveTo evaluate the outcome of primary versus secondary ureteroscopy for pediatric ureteral stones.Patients and methodsA retrospective chart review study that included 66 children aged less than 12 years, who were subdivided into two groups: Group A, which included 42 children who had undergone primary ureteroscopy without pre-stenting; and Group B, which included 24 children who had undergone ureteroscopy after ureteric stenting. Kidneys, ureters and bladder radiographs were done on the first postoperative day to assess the degree of stone clearance and stent position.ResultsAge, gender, stone location and stone size were not significantly different between both groups. In Group A, 31 (73.8%) children required ureteric dilation, 13 (31%) had a tight ureter that failed to respond to dilation, 25 (59.5%) displayed complete stone clearance, and of these, 13 (52%) needed postoperative stenting. One child experienced ureteric injury during stone disintegration and was stented for two weeks. Children in Group B experienced a 95.8% complete stone clearance rate, with no ureteric injury reported; postoperative stenting was performed in three (12.5%) children..ConclusionSecondary ureteroscopy is preferable over primary ureteroscopy in pediatric populations because of a significantly lower need for ureteric dilation, shorter procedure time and better stone clearance rate..     

High incidence of urinary stones in Uyghur children may be related to local environmental factors

ObjectiveTo analyze the causes of urolithiasis in Uyghur children from Xinjiang.Patients and methodsWe retrospectively evaluated the clinical features and characteristics of urinary stone composition of 220 Uyghur pediatric patients with urolithiasis between March 2009 and June 2011. The data were compared with that of 100 Uyghur children without urolithiasis who visited the Child Care Clinic for regular health check-ups. The stones were collected by endoscopy or open surgery, and analyzed using infrared spectroscopy.ResultsThe mean age of the 220 Uyghur children was 7.48 ± 4.73 years (range, 0.8–17.0 years). The overall sex ratio (male:female) was 2.23:1. The predominant pure stone was ammonium urate (58.9%), whereas the predominant mixed stone was calcium oxalate mixture (91.1%). Uric acid stones comprised 54% of all stones. Urinary tract infections were observed in 42.3% and 4.0% of the patient and control groups, respectively. The mean urinary pH values were 5.77 ± 0.67 and 6.42 ± 0.67, respectively (p < 0.001). pH values were <5.5 in 52.7% and 6% of the patient and control groups, respectively. On 24-h urine analysis, we found metabolic disturbances in these patients: hypercalciuria in 6.8% cases, hyperphosphaturia in 16.8% cases, hyperuricosuria in 21.4% cases, and hypomagnesiuria in 34.1% cases.ConclusionsUrolithiasis in Uyghur children may be primarily related to local environmental factors.     

Pediatric urolithiasis with renal failure: Siut experience

PurposePediatric urolithiasis is endemic in Pakistan and constitutes about 13% of all urolithiasis cases. Urolithiasis associated with renal failure is one of the most important cause of pediatric ESRD in Pakistan.Material and methodsRetrospective analysis of 402 children with urolithiasis and associated renal failure. Ultrasound was the mainstay of radiological diagnosis and assessment.Results402 patients, age ranged between 9 months to 14 years with male female ratio of 2:1. More than 50% had a positive family history of stone disease. Apart from obstruction and infection, poor socioeconomic status (89%), rural residence (66%), neglect and delay in acquiring treatment led to renal failure in these patients. The most common signs and symptoms were fever (56.7%), flank pain (55.2%), shortness of breath (38%) and vomiting (38.3%). 105 (26%) were anuric at presentation and 297 (74%) non-anuric. More than 60% of these patients had bilateral stones and associated urinary tract infection. The initial management of these patients required dialysis mostly peritoneal dialysis in small children. Percutaneous nephrostomy with or with out dialysis was also the main stay of initial management especiallyfor those presenting with a pyonephrosis. In some “Double J” stents were also placed to relieve obstruction. Details of operative procedures for definitive treatment and type of stones will be provided in presentation.ConclusionsAbout 70% of the patients had good recovery of renal function. These good results were achieved because of the provision of free high technological treatment to all our patients under one roof with close co-operation of pediatric urology, nephrology and intensive care teams.     

Effect of size and site on the outcome of extracorporeal shock wave lithotripsy of proximal urinary stones in children

ObjectiveTo determine the effect of location and size of stones on the outcome of extracorporeal shock wave lithotripsy (ESWL) in children.Patients and methodsIn 2008–2010, 150 children (median age 6.6 years) with radio-opaque ureteric and renal stones measuring ≤4 cm were treated. Exclusion criteria were coagulation disorders, pyelonephritis, distal obstruction, non-functioning kidney and hypertension. ESWL was performed under general anesthesia. Follow up period was 5–22 months.Results186 stones were treated: 76 calyceal, 92 pelvic and 18 proximal ureteral. Mean stone size was 1.3 cm. A total of 312 sessions were performed (mean per stone = 1.67 sessions). The mean number of shock waves per session was 2423.68. Overall stone-free rate was 89.24%. Having a calyceal location did not significantly affect the stone-free rate (p = 0.133). The failure rate was significantly higher (66.7%) in stones >3 cm in size (p < 0.001). Complications were encountered in 18 patients; 2 underwent auxillary ureteroscopy and 4 uretrolithotomy for treatment of steinstrasse.ConclusionESWL is a safe and effective method for treatment of stones up to 2 cm in children. Rate of auxillary procedures increases in stones >2 cm in size. About 80% of failures were associated with stone size >1.35 cm while 52.3% of completely cleared stones were associated with size <1.35 cm.     

Safety of ungated shockwave lithotripsy in pediatric patients

ObjectiveUngated extracorporeal shockwave lithotripsy (ESWL) in adults is associated with cardiac arrhythmias. We report on the safety and efficacy of this method for treatment of renal calculi in children.Patients and methodsChildren under 14 years with radio-opaque renal stones were treated by ungated ESWL. Pre-treatment plain radiographs and intravenous urography and post-treatment ultrasonography and plain films were used to follow up clearance of fragments. All children were monitored for arrhythmias.ResultsThirty-seven children (28 males, nine females) with a median age of 5 years (range 2–14 years) underwent 69 ungated ESWL sessions for renal calculi. Nineteen children had stones located in the left kidney, 17 had stones located in the right kidney and one child had bilateral renal stones. The stone size ranged from 6 to 25 mm (mean 9.9 mm). Shockwave number ranged from 800 to 3650 (mean of 2500 shockwaves per session). All children underwent lithotripsy with a gradual incremental energy increase from 14 to 20 kV. No patient had cardiac arrhythmias or other intra-procedural complications. No patient required conversion to gated ESWL. The overall stone-free rate was 86%.ConclusionThe results suggest that ungated ESWL is safe in children under 14 years. The efficacy was comparable to that of gated ESWL from previously published series.     

Minimally invasive percutaneous nephrolithotomy in preschool age children with kidney calculi (including stones induced by melamine-contaminated milk powder)

Purpose

This study was undertaken to assess the safety and efficacy of minimally invasive percutaneous nephrolithotomy (mini-PCNL) using ureteroscope and pneumatic intracorporeal lithotripsy in preschool age children with kidney calculi.

Methods

We studied 27 renal units in 20 patients of preschool age (≤6?years) who underwent mini-PCNL at our institute. The mean age was 42.6?months (range 14–68?months). The average stone burden was 1.85?cm (range 0.9–2.8?cm). Eight patients aged 14 to 58?months had been exposed to melamine-tainted powdered formula. The mini-PCNL was performed with an X-ray-guided peripheral puncture. Minimal tract dilatation was undertaken to fit a 14–16?Fr peel-away sheath. Ureteroscope and pneumatic intracorporeal lithotripsy were used to fragment the stones.

Results

Complete clearance was achieved in 23 renal units (85.2?%) with mini-PCNL monotherapy. This has increased to 92.6?% after adjunctive ESWL. The average fall in hemoglobin was 1.28?g/dL. None of the patients required blood transfusion. The median length of hospital stay was 8.2?days. Patients were followed up every 6?months for 2?years. There has been only one recurrence of stone and no long-term complications.

Conclusion

Mini-PCNL is a effective treatment for pediatric kidney stones refractory to extracorporeal shock wave lithotripsy, including stones induced by melamine-contaminated milk powder. The “mini-PCNL” technique, which uses ureteroscope and pneumatic intracorporeal lithotripsy, is a safe and feasible modality for treating renal calculi in preschool age children.     

Does previous open nephrolithotomy affect the outcomes and complications of percutaneous nephrolithotomy in children?

ObjectiveTo analyze the success and complication rates of percutaneous nephrolithotomy (PCNL) performed in pediatric patients and to compare outcomes of the patients undergoing primary PCNL with those of patients who had undergone previous open nephrolithotomy.Materials and methodsBetween 2000 and 2011, PNL procedures were performed in 123 renal units (RU) of 111 children. We compared RU on which previous open surgery had been performed (group 1 RU = 26) on the same kidney with RU that had not been involved in previous surgery (group 2 RU = 97). Patient characteristics, pre- and postoperative hematocrit and creatinin levels, operative time, fluoroscopic screening time, stone free rate, complications and hospitalization time were documented and compared.ResultsThere were no significant differences between the groups in sex, stone burden, pre- and postoperative hematocrit levels. Mean age and pre- and postoperative creatinin levels were significantly higher in group 1 (p < 0.05). Mean operative time, fluoroscopic screening time and hospitalization times were similar in each group (p > 0.05). The stone free rates after PCNL were 65.4% in group 1 and 81.4% in group 2 (p > 0.05). Multiple access rate was higher in group 1; however, this was not statistically significant (27% vs. 15%, p > 0.05).ConclusionPCNL can be performed in pediatric patients who have previously undergone open nephrolithotomy but the success rates may be lower and risk of bowel injury higher. NCCT should be considered preoperatively for patients who have previously undergone open renal surgeries to investigate the presence of retrorenal colons. Our study includes relatively few patients with a history of open surgery and we believe that additional clinical studies with larger numbers of patients are needed to confirm our initial findings.     

Does percutaneous nephrolithotomy in children cause significant renal scarring?

ObjectiveTo determine the frequency of renal parenchymal damage following percutaneous nephrolithotomy (PCNL) in children.Patients and methodsFifty-six children undergoing PCNL in 60 renal units between January 2000 and December 2004 were included in this prospective study, and were subjected to postoperative technetium-99m dimercaptosuccinic acid (^99mTc-DMSA). Using a standard questionnaire, demographics, number, size and location of stones, procedure details, outcome as indicated by clearance with PCNL alone or additional procedures, and follow up were documented. Presence of focal renal damage and its association with the PCNL tract were examined.ResultsOut of 60 renal units, cortical defects on ^99mTc-DMSA scan were seen in 10 renal units (17%). In three of these kidneys, the site of focal defect corresponded to the access site for tract formation during PCNL. Two additional kidneys had scarring at multiple sites, one of which corresponded to the access site during PCNL. In the remaining five kidneys no association between focal renal damage and nephrostomy tract site could be ascertained. No association was seen between renal damage and the size of nephroscope used during PCNL.ConclusionThere exists a risk of focal damage to renal parenchyma from the formation of the nephrostomy tract. In our series, focal damage was seen in 5% of patients; this may be an overestimate since preoperative ^99mTc-DMSA scans were not available for our patients. Meticulous technique is important combined with a smaller nephroscope to minimize renal damage. Long-term follow up of such children is required to assess how many are left with permanent renal scars.     

Urinary stone disease in the first year of life: is it dangerous?

Purpose

We have evaluated the clinical, radiological and metabolic features of infantile urolithiasis (UL).

Materials and methods

We have reviewed the medical records of 93 children who were diagnosed as having UL before 1 year of age. We recorded patient demographics, the age at diagnosis, presenting symptoms, family history, the localizations and dimensions of stones, urinary metabolic examinations, as well as physical, laboratory, and radiologic findings. Our secondary objective was to compare some features of this group with those of older children with UL followed-up in the same clinic which were previously reported.

Results

We evaluated 93 children referred to our pediatric nephrology clinics. A family history of UL was 56.2 % in the study group. Resolution of stones was observed in 30.1 % of the cases. Urinary tract infections (UTIs) were detected in 65.9 % of females and 46.2 % of males. At least one urinary metabolic abnormality was found in 79.5 % of all the children. Most commonly seen metabolic abnormality was hypercalciuria. In all patients stones were located in kidneys except one infant who had an ureteral stone together with a kidney stone. Fifteen (16.1 %) children had an accompanying systemic disorder.

Conclusions

Among pediatric urinary stone diseases infantile UL can be regarded as a separate clinical entity. Coexistence of systemic disorders and anatomic anomalies at high frequencies may indicate a role of distinct pathogenetic mechanisms. In addition, high rates of UTIs and metabolic abnormalities in this age group justify screening for these parameters during follow-up of these children.     

Pediatric urolithiasis in a non-endemic country: A single center experience from The Netherlands

ObjectiveTo provide insight in causative factors of pediatric urolithiasis in The Netherlands, a non-endemic country.Patients and methodsData from 71 children with urolithiasis and stone analyses between 1996 and 2010 in the Radboud University Nijmegen Medical Centre were studied retrospectively. Patients (48 boys, 23 girls, ratio 2.1:1) were aged 0.5–18.3 years (mean 8.8, SD 5.6). All stone analyses were performed with FTIR spectroscopy.ResultsOf the 49 patients with metabolic analysis, 78% showed one (n = 15) or more (n = 23) metabolic abnormalities. Forty-seven percent had hypercalciuria (n = 23), 31% had hyperoxaluria (n = 15), 29% hypocitraturia (n = 14), 10% hyperuricosuria (n = 5), 10% cystinuria (n = 5), and 6% had hypomagnesiuria (n = 3).Sixty-one percent of the stones were composed of calcium phosphate, calcium oxalate, or a combination of those. Twenty-six percent consisted of pure or mixed magnesium ammonium phosphate, 8.3% pure or mixed urate, and 8.3% cystine.ConclusionChildren with urolithiasis in The Netherlands show stone composition similar to other Western European countries. However, a high percentage of metabolic abnormalities (78%) was found, indicating the need for extensive evaluation of pediatric urolithiasis to find underlying causes and thereby prevent stone recurrences. A close collaboration between a pediatric nephrologist and urologist is mandatory for optimal surgical and medical treatment.     

A correlation study between macro- and micro-analysis of pediatric urinary calculi

ObjectiveThe aim was investigate the relationship between macro- and micro-compositions of pediatric urinary stones by using two combined analytical techniques: Fourier transform infrared spectroscopy (FT-IR) and inductively coupled plasma-optical emission spectrometry (ICP-OES).Materials and methodsA total of 74 consecutive urinary calculi were collected from children. Each stone was divided into two equal portions. One part was analyzed by FT-IR to determine mineralogical composition. The second part underwent analysis by ICP-OES to determine the heavy metals and trace elements contents. The association between mineralogical components and elemental contents was evaluated.ResultsThe percentages of mineralogical components of the stones were 78.3% calcium oxalate monohydrate, 63.5% calcium oxalate dihydrate, 24.3% ammonium urate, 13.5% uric acid, 10.9% dahllite, 12.1% brushite, 8.1% ammonium calcium phosphate, 8.1% struvite, 4.5% cysteine, and 2.7% were xanthine. There were seven elements with significant different high concentrations; magnesium, sulfur, strontium, lead, chromium, calcium, and phosphorous. High calcium-containing stones had significant higher contents of magnesium, lead, strontium, and zinc (p < 0.05) than low calcium-containing stones. Phosphate stones had significant contents of magnesium, strontium, zinc and chromium when compared to other stones (p < 0.05).ConclusionsPediatric urinary stones have variable biochemical structures. The stones contained many significant heavy metals and trace elements in different concentrations, and phosphate stones enclosed most of the heavy and trace elements.     

Use of Lma Stonebreaker as an Intracorporeal Lithotrite in the management of Ureteric Calculi

PurposeLMA StonebreakerTM is a new type of ballistic intracorporeal lithotrite , which does not require any external electrical power or access to compressed air . It is small in size and portable . This study aims at evaluating the efficacy, safety and cost effectiveness of this lithotrite in the management of ureteric calculi in children.Material and Methods10 children with ureteric calculi requiring intracorporeal lithotripsy were prospectively included in the study. The size of the stone, position of the stone, number of shocks required to fragment the stone to effect complete clearance and degree of retropulsion were documented in each case, and any evidence of urothelial trauma was noted.ResultsAll stones were satisfactorily fragmented and all were rendered stone free . The mean of shocks needed to fragment the stones was 6. The incidence of retropulsion was 10%. There was no evidence of urothelial trauma noted in any of the patients.ConclusionsLMA StonebreakerTM is a safe, effective, cost effective, robust and portable device for intracorporeal lithotripsy in children.