Urolithiasis bei Kindern – rationelle Diagnostik, Therapie und Metaphylaxe

With a proportion of 1–5%, children constitute only a small number of all patients with urolithiasis. Nevertheless, pediatric stone disease is an important health care problem because of the high recurrence rate and the threat of progredient renal function impairment with consecutive loss of quality of life. Modern therapies, especially extracorporeal shock wave lithotripsy (ESWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL), have caused a revolution in the operative treatment spectrum. Open surgery is required for stone removal only rarely, such as for the simultaneous repair of urinary tract anomalies. The minimally invasive modalities of modern stone therapy – mainly ESWL as the treatment of first choice – have led to widespread disregard of stone metaphylaxis. The important principle that says an urinary stone is just a symptom and not the cause of the disease is often forgotten. So it must be noted that despite the high standard of care in Germany, not all problems regarding urinary stone disease are being resolved, particularly in childhood. This article presents the current knowledge of the most important aspects of stone therapy and the methods of treatment in children.     

Metaphylaxis of nephrolithiasis

The introduction of extracorporeal shockwave lithotripsy (ESWL), with its noninvasive removal of stones and considerable reduction in the morbidity of stone disease, has revolutionized the therapy of urolithiasis. Unfortunately the propensity for stone recurrence is not altered by removal of stones with ESWL and stone recurrence is still about 50%. Progress in medical treatment has shown how different therapies can prevent the stone recurrence, even though it is often difficult to predict which patient will go on to become a recurrent stone former. With the right evaluation, however, the cause of calculi formation can be treated in 97% of the patients. Primary prevention of urolithiasis includes general prophylaxis in a no-risk population that has never been affected by urinary tract stones, is without familial predisposition, metabolic or genetic alterations, or urinary tract abnormalities or infections and who live in a geographical area that is at risk. Secondary prevention or metaphylaxis of stone disease is aimed at the population at risk, that is patients already affected by the stone disease, with familial predisposition, with urinary tract alterations, with metabolic or genetic alterations (gout, bone or bowel diseases) and urinary infection.     

Multimodal treatment (extracorporeal shock wave lithotripsy and endourology) of complicated renal stone disease

From October 1983, (installation of the extracorporeal shock wave lithotripsy unit) to August 1985, 207 patients presented at the Katharinenhospital Stuttgart with complicated renal stone disease (70 borderline stones, 77 partial and 60 complete staghorn calculi). 197 patients were treated with the new technology for urinary stone therapy, i.e. extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PCN), and ureterorenoscopy. The combination of PCN and ESWL proved to be the optimal therapeutic approach in the majority of cases (44%), particularly for partial and complete staghorns, whereas PCN or ESWL monotherapy are indicated for borderline stones (51% ESWL, 26% PCN, 20% combination, 3% surgery) and selected cases of staghorn calculi only. Based on this treatment policy (minimal invasiveness and morbidity), 75 patients with partial staghorn (21% ESWL, 28 PCN, 44% combination, 7% surgery) and 52 cases of complete staghorn stone (2% ESWL, 13% PCN, 74% combination, 11% surgery) have been treated successfully. The rate of major complications was low (2.5% septicemia, 2% major renal hemorrhage, 0.5% mortality). With this new concept of multimodal therapy (ESWL and endourology), even cases of malignant stone formation ('stone cancer') may be treatable, since these methods can be applied repeatedly without damaging the renal parenchyma.     

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.     

Extracorporeal shock wave lithotripsy in paediatric patients

24 children with urolithiasis of the upper urinary tract were treated by extracorporeal shock wave lithotripsy (ESWL). In all patients sufficient stone disintegration could be achieved by an average of 950 shock waves. Percutaneous nephrostomy was required for "Steinstrasse" ureteral obstruction in 2 cases. At discharge from hospital 16 children were considered stone-free. Follow-up showed 90% of the children to be stone-free without recurrence (mean 20 months). The necessary precautions considered, ESWL is the method of choice for treatment of urolithiasis of the upper urinary tract in children. The long term effects of ESWL on the juvenile kidney have yet to be observed.     

Pediatric urolithiasis: review of research and current management

The treatment of urolithiasis in children has changed dramatically in recent years. With the proven safety and efficacy of extracorporeal shock wave lithotripsy (ESWL), percutaneous lithotripsy and ureteroscopy in adults, these modalities are now in the forefront of the treatment of pediatric urinary stones. Our research in the juvenile non-human primate with ESWL indicates that renal damage in most cases is neither significant or persistent. In addition, technological advances in instrumentation have cleared the way for the use of percutaneous lithotripsy and ureteroscopy in most pediatric patients. Today, open surgical procedures for stone disease in children should be a last resort.     

Arterial blood pressure following different types of urinary stone therapy. Presented at the 8th European Symposium on Urolithiasis, Parma, Italy, 1999

OBJECTIVE: Several studies reported increased blood pressure (BP) values following extracorporeal shock wave lithotripsy (ESWL) treatment of renal stones. It is unclear, however, whether this is due to ESWL, since nephrolithiasis itself increases the relative risk of developing hypertension. Therefore we prospectively studied the BPs of stone patients undergoing different types of treatment. METHODS: 252 stone patients (63% males, 37% females, median age 44.3, range 11.7-86.4 years) participated. 168 suffered from uretral stones: 50 underwent ESWL; 40 ureteroscopy, and 78 patients passed stones spontaneously (SP). 84 had renal stones: 60 underwent ESWL; 8 percutaneous nephrolithotomy/open surgery, and 16 no treatment. Systolic (SBP) and diastolic (DBP) BP were measured according to Riva-Rocci prior to, immediately after, and 3, 6, 12, 18 and 24 months after stone therapy. RESULTS: Immediately after SP, SBP decreases, whereas after active stone treatment increases (highest after ESWL) in SBP were seen. DBP was unchanged. During the further follow-up, a gradual increase in BP was observed in all groups. At 24 months in all groups, regardless of the stone location and type of treatment, SBP and DBP were significantly higher than the pretreatment levels (p = 0.000). There was no a difference between renal and ureteral stones, or between the ESWL treatment and the other groups. CONCLUSION: Renal stone disease itself rather than the type of treatment significantly increases SBP and DBP during a follow-up period of 24 months. The underlying mechanisms remain to be elucidated.     

Ureteral stricture after ESWL for ureteral calculi

BACKGROUND: There are many reports on the effects of ESWL, but few reports on the complications, especially remaining ureteral stricture after this treatment. Therefore we have retrospectively reviewed our cases to define the predisposing factors of this complication. METHODS: Since 1991 we have treated urolithiasis with ESWL using a Siemens Lithostar for the first therapy. We had 16 cases of ureteral stricture after this treatment. Ureteral stricture is the most common complication after ESWL treatment. To define the risk factor of the stricture we have compared 549 cases that were successfully treated between 1994 and 1996 without this complication. In these two groups we examined ages, sexes, chief complaints, size, position and components of the calculi, the degree of hydronephrosis, the frequency of ESWL, the presence of urinary tract infection, the duration of stone impaction and the after endourological treatment using multiple logistic regression analysis. RESULTS: Patients with the stone incidentally found and those with the UTI seemed to be more frequently associated with ureteral stricture, however there was not a significant difference. The hydronephrosis more than grade 3 (p = 0.025), the frequency of ESWL (p = 0.0325) and the after endourological treatment, especially TUL (p = 0.0184) were statistically significant among the other factors. The stricture occurred in 5 out of 29 patients with the hydronephrosis of grade 4 and 5 between 1994 and 1996. CONCLUSION: We should carefully treat patients with grade 3 or more hydronephrosis with ESWL. We should not repeatedly treat the patients with ESWL. We should take care of TUL treatment after ESWL.     

影响第二次冲击波碎石术治疗上尿路结石患者成功的因素分析

目的 探讨影响第二次冲击波碎石术（extracorporeal shock wave lithotripsy, ESWL）治疗上尿路结石患者成功的因素。方法 回顾性分析2008年1月至2012年12月来本院接受第二次ESWL治疗的上尿路结石患者120例。根据患者上尿路结石有无完全排出分为成功组（n=80）和失败组（n=40）。回顾性分析所有患者的病历资料,相关因素分析包括性别、年龄、病程、BMI、结石侧别、结石位置、结石长度、结石宽度、结石数目、肾绞痛、血尿、肾积水程度、非增强螺旋CT值、冲击次数、冲击能量等指标。应用单因素、多因素非条件Logistic回归分析上尿路结石患者第二次ESWL治疗成功与否的危险因素分析。结果 120例上尿路结石患者临床特征显示,两组在病程、BMI、结石长度、结石宽度、结石数量、肾绞痛、肾积水程度、CT值、冲击次数方面差异有统计学意义（P＜0.05）,在性别、年龄、结石侧别、结石位置、血尿、冲击能量方面差异无统计学意义（P＞0.05）。经单因素、多因素 Logistic 回归分析结果显示,BMI偏高、结石长度＞2 cm、存在肾绞痛、肾积水程度严重、CT值＞750 HU会增加上尿路结石患者第二次ESWL治疗失败的风险（P＜0.05）。结论 临床医师利用ESWL第二次治疗上尿路结石患者过程中,应格外注意患者BMI、结石长度、肾绞痛、肾积水程度、CT值等关键指标。     

Nierenkelchsteine

The natural course of untreated, asymptomatic calyceal calculi has not yet been clearly defined regarding disease progression and risk of surgical interventions. The decision for an active treatment of calyceal calculi is based on stone composition, stone size and symptoms. Extracorporeal shockwave lithotripsy (ESWL) has a low complication rate and is recommended by the current guidelines of the German (DGU) and European (EAU) Associations of Urology as a first-line therapy for the treatment of calyceal stones <2 cm in diameter. However, immediate removal of stones is not achieved with ESWL. The primary stone-free rates (SFR) after ESWL depend on stone location and stone composition and can show remarkable differences. Minimally invasive procedures, such as percutaneous nephrolitholapaxy and ureteroscopy are alternatives for the treatment of calyceal stones which have low morbidity and high primary SFR when performed in centres of excellence.     

The management of paediatric urolithiasis

OBJECTIVE: To evaluate the efficacy and safety of the management of paediatric urolithiasis by extracorporeal shock wave lithotripsy (ESWL), endoscopic ureterolithotomy, percutaneous nephrolithotomy (PCNL) and open nephrolithotomy. PATIENTS AND METHODS: In a 3-year period (1997-1999), 59 children were treated for urolithiasis and underwent a total of 79 procedures. Thirty-two ESWL sessions were performed in 23 children (mean age 7.4 years, median 6.0). PCNL was undertaken in 30 renal units in 25 children (mean age 6.4 years, median 4.0). Eight patients (mean age 7.8 years, median 5) underwent 17 ureteroscopic procedures, six of which involved the use of a holmium laser. Three children with staghorn calculi underwent open nephrolithotomy under conditions of renal ischaemia and hypothermia. RESULTS: Of the 23 children treated using ESWL, 21 (91%) became stone-free; 17 underwent one ESWL session (74%), three had two sessions and three (13%) had three sessions. All eight patients who underwent ureteroscopy became stone-free. Four patients in whom the stone could not be reached by ureteroscopy initially had a JJ stent inserted, and the stone and stent subsequently removed. Stones were cleared using PCNL in 27 of 30 renal units (90%); three patients who had residual stone fragments were rendered stone-free by ESWL. Two of three children undergoing open nephrolithotomy were stone-free after surgery and the remaining one rendered stone-free with ESWL. Metabolic evaluation showed that 25 of 45 children (55%) had a urinary infection, eight (18%) had hyperoxaluria, three (7%) had hypercalciuria, two (4%) had cystinuria, and no identifiable cause was found in seven (16%). Treatment by a single modality rendered 52 of the 59 children (88%) stone-free; when the different modalities were combined, 57 of 59 patients (97%) were cleared of their stones. CONCLUSIONS: Technological advances in ESWL, ureteroscopy and PCNL have had a significant effect on the management of urolithiasis in children, allowing a safe and successful outcome. The comprehensive care of children with urolithiasis should include a full metabolic evaluation. Anatomical anomalies contribute to the complexity of many cases, necessitating a close liaison between adult and paediatric urologists, nephrologists and radiologists to optimize stone management in children.     

Electromagnetic extracorporeal shock wave lithotripsy in children

Extracorporeal shock wave lithotripsy (ESWL) was performed for the treatment of urinary tract calculi in 28 children. All treatments were done with the standard Siemens Lithostar device in situ: no special adaptations for adequate positioning of children are required to target the stone precisely. A total of 42 calculi in 30 renal units was treated, requiring 50 ESWL sessions. The mean energy used was 16.4 kv. and the number of shock waves averaged 3,188. Mean fluoroscopy time per session was 1.5 minutes. In 26 of 50 sessions (52%) general anesthesia was needed for the child to remain perfectly still. A complete stone-free rate was achieved in 38 of 42 calculi (90.5%): after 1 session in 30 (71.4%), after 2 sessions in 6 (13.7%) and after 3 sessions in 2 (4.8%). Five staghorn calculi were treated with ESWL monotherapy. A complete stone-free result was obtained after 3 treatments in 2 patients, while 2 had residual fragments in the lower pole (5 mm. after 6 sessions and 11 months of followup in 1, and 7 mm. after 3 sessions and 3 months of followup in 1). A cystine staghorn stone necessitated open nephrolithotomy after 3 sessions without any fragmentation. One impacted sacroiliac ureteral stone required endoscopic laser lithotripsy. Except for these 2 failures no adjuvant procedures were needed. There were no intraoperative or postoperative complications and minor skin bruising at the coupling site after 3 treatments did not require any therapy. We conclude that electromagnetic ESWL with the standard Lithostar unit is a safe and effective method to treat calculi throughout the urinary tract in children.     

Interdisciplinary treatment of gallstones: surgery, endoscopy, lithotripsy. Report of experiences after 4 years

Today, several methods of treatment for gall stone disease exist besides standard surgical procedures: endoscopy, lithotripsy, litholysis or a combination of the above. During the last four years 1786 patients were treated using an interdisciplinary approach. Cholecystectomy was still the most frequent method of treatment for symptomatic cholecystolithiasis (n = 1369) with low morbidity (4.3%) and lethality (0.28%). Probably less than 20% of all cases fulfill the strict selection criteria for extracorporeal shock wave lithotripsy (ESWL). All alternative methods of treatment in which the gallbladder is preserved have an increased risk for gall stone recurrence. Only after the long-term follow-up results of ESWL are known, the recurrence rate can be assessed. In most cases, bile duct stones (n = 417) were removed by endoscopy, if necessary in combination with ESWL (n = 310, stone removal: 95%, lethality: 0.3%). However, in low risk patients with concurrent cholecystolithiasis surgery was still the method of choice (n = 107, stone removal: 96%, lethality: 0/107). It seems not so important as to who performs the non-surgical procedures in the treatment of gall stones - the surgeon, internist or radiologist. Moreover, an interdisciplinary approach should be sought.     

体外冲击波碎石治疗儿童尿路结石的疗效观察(附62例报告）

目的：探讨体外冲击波碎石(ESWL)治疗儿童尿路结石的有效性和安全性。方法：采用ESWL治疗儿童尿路结石患者62例，其中肾盂肾盏结石35例，输尿管结石22例，膀胱结石4例，移植肾结石1例。结果：62例随访3个月，结石排净59例(95．2％)，结石残留2例(3．2％)，1例无效(1．6％)，改用手术治疗。结论：ESWL治疗儿童尿路结石安全、有效，是儿童尿路结石的首选治疗方法。     

Extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy in children

The possibilities for treating children with renal stone disease by extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL) have not been widely explored. We report ten children, aged between 5 and 16 years, treated by PCNL, and six children, aged between 6 and 15 years, treated by ESWL alone. A 16-year-old spina bifida child with a staghorn calculus was treated electively by a combination of the two methods. Hospital stay was 3 to 8 days for treatment by PCNL or ESWL, and was only 11 days for the combination treatment. Complete stone clearance was achieved in 12 children followed for 3 months. No significant complications occurred. ESWL and PCNL are suitable methods for the management of renal calculi in children.     

Extracorporeal shock wave lithotripsy in children: experience using a mpl-9000 lithotriptor

Our objectives were to assess the value of extracorporeal shock wave lithotripsy (ESWL) in treating pediatric urolithiasis, and to determine the factors that may affect treatment success. Between January 1993 and August 2002, 129 children with upper urinary tract calculi (134 renoureteral units) were treated using a Dornier MPL-9000 lithotriptor. The series consisted of 77 boys and 52 girls with an age range from 20 months to 14 years (average age: 8.7 years). All ESWL procedures took place under general anaesthesia or sedation with ketamin or fentanyl. Under ultrasonic or fluoroscopic guidance, children were treated with a maximum 2,550 shocks at an average of 19.5 kV. Success was defined as the lack of any visible stone fragments on post-treatment radiological evaluation. The patients were assessed 3 months after ESWL treatment and the results were compared using ²-tests to detect factors that might be associated with treatment success. There were 105 renal, 20 ureteral, four bilateral renal and one unilateral renal plus contralateral ureteral calculi. The mean sizes were 15.7 mm for pelvic, 17.8 mm for renal and 10.2 mm for ureteral stones. One or two lithotripsy sessions were sufficient in most cases (71.6%). In 15 (11.6%) patients, double J stents introduced before lithotripsy were left indwelling until all stone fragments were voided. Overall success rates were 89.5% for pelvic, 85.5% for renal and 75% for ureteral stones. Complications such as urinary tract infection, Steinstrasse and small subcapsular hematoma occurred in 19 (14.7%) patients. The only significant factor associated with the stone-free rate was the diameter of the stone (P=0.022). This study confirmed that the stone-free rate is significantly influenced by stone size. Because children with stone disease are at risk for a longer period than adults, their cumulative likelihood of stone recurrences may be higher. Thus, we agree with other authorities that minimally invasive treatment, such as ESWL, is mandatory in children with urolithiasis.     

Efficacy of extracorporeal shock wave lithotripsy for solitary lower calyceal stone: a statistical model

OBJECTIVE: To evaluate the effect of inferior calyceal radiographic anatomy, number of extracorporeal shock wave lithotripsy (ESWL) sessions and stone size on the successful clearance of solitary inferior calyceal calculi after ESWL. PATIENTS AND METHODS: In a prospective study between January 2001 and November 2002, 66 renal units with a solitary inferior calyceal calculus of < or = 2 cm were treated with electrohydraulic ESWL. The infundibulopelvic angle (two definitions), infundibulovertebral angle, inferior calyceal infundibular diameter, infundibular length, cortical thickness over the lower pole, number of minor calyces and stone size were determined from intravenous urography before treatment. The number of ESWL sessions was also included in the analysis. Treatments which produced residual fragments not clearing within 3 months of satisfactory fragmentation were considered as failures. All patients in whom the treatment failed were treated successfully by percutaneous nephrolithotomy. The data were then analysed using two different statistical methods; first by intravariable differences using the test of proportion (Fisher's test) and then all the variables together using logistic regression. RESULTS: At 3 months 78.8% of the renal units were clear of stone. All intravariable differences were statistically significant except stone size (<1 cm, 1-2 cm). In a multivariate analysis of all variables, only stone size was the most important predictor for successful stone clearance (P = 0.03). CONCLUSIONS: ESWL is the initial treatment of choice in selected patients with inferior calyceal stones. The stone size appears to be the most important predictor for stone clearance.     

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 in-dicated 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.     

Extracorporeal shock wave lithotripsy of impacted radiolucent stone at the right pyeloureteric junction and oral dissolution therapy in a patient with transplanted liver: a case report

Extracorporeal shock wave lithotripsy (ESWL) is a safe, effective method to treat urinary lithiasis. The success rate in ESWL depends on stone location, size, number, and fragility as well as calceal anatomy and patency of the urinary tract. An association of calcineurin inhibitors and uric acid urolithiasis has been reported in renal allograft recipients, but the mechanism remains unknown. Herein we have reported the case of 68-year-old male patient who developed cryptogenic cirrhosis and underwent liver transplantation. Seven years after transplantation, the patient was admitted to the hospital with right renal colic. An 8.9-mm radiolucent stone at the pyeloureteric junction was associated with moderate consecutive hydronephrosis. The second stone was located in a lower renal calyx. After a failed attempt at retrograde ureteral stenting, we performed a percutaneous nephrostomy. Antegrade pyelography with following ESWL treatment resulted in disintegration of the obstructive stone at the pyeloureteric junction. Afterward, we performed antegrade placement of a double-J stent. Residual stones in the lower renal calyx were successfully treated with a 3-month course of oral intake of a dissolution agent-potassium sodium hydrogen citrate. In this case, we have discussed ESWL and oral dissolution therapy of radiolucent stones in a hydronephrotic right kidney, which resulted in stone-free disease after 3 months of combined therapy. There was neither clinical nor biochemical damage to the transplanted liver.     

Treatment of ureteral stone disease: the role of ESWL and endourology

Summary In recent years, extracorporeal shockwave lithotripsy (ESWL) has proved a safe and easily reproducible method for the treatment of calculi in the upper urinary tract above the iliac crest. Current indications for ESWL as single therapy encompass approximately 60%–70% of all stones. The use of endourological methods as auxiliary procedures can enhance the range of indications to 95% of all renal stones and 85% of all ureteral stones. In the last year, 1340 patients have been successfully treated for urinary calculi at our department. Evaluation of all stone cases shows that ESWL alone, ESWL combined with percutaneous techniques, or percutaneous techniques alone were performed on 93% of all patients. Only 7% of patients had to undergo open surgical treatment, 1% for renal stones and 15% for ureteral stones. Ureteral stones are still among the problem stones for ESWL, in many cases requiring time-consuming combined procedures with either of the percutaneous methods. Furthermore, ureteral obstruction caused by stone particles as a complication after ESWL-treatment of large renal stones has to be relieved using percutaneous techniques. In this report we describe our approach in detail and discuss our results.