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PubMed2001

Pediatric urolithiasis.

Pediatric stone disease is a frequently underestimated entity that can present unique problems in its management. The condition stems from any of a number of underlying, causative factors, and the significant possibility of recurrence must always be borne in mind. The primary care physician should be aware that the condition is readily treatable by an experienced pediatric urologist who has a range of treatment modalities at his or her disposal; however, overall success is governed by a timely referral and subsequent long-term follow-up to ensure the maintenance of a stone-free state.

Child↗

PubMedDate not supplied

Comparison of spiral CT and US in the evaluation of pediatric urolithiasis.

The objective of the study was to determine the value of spiral computerized tomography (CT) in detecting urolithiasis in pediatric patients and compare its efficacy with ultrasound (US). Twenty-nine infants aged between 2 to 94 months with clinical presentation suggestive of urolithiasis and a negative or indeterminate plain film were included in the study. Abdominal US and spiral CT were performed in all patients. Presence, size and localization of stones were noted for each patient on both CT and US. The diagnosis of urolithiasis was confirmed by passage of stones spontaneously, extracorporeal shockwave lithotripsy (ESWL), surgery, or clinical follow-up. Presence of stones was confirmed in 23 of 29 patients (79%). Eight patients had single stone and the remaining 15 had multiple stones either in a single localization (single kidney or single ureter) or multiple localizations. Spiral CT detected 57 stones (45 renal and 12 ureteral). US detected 34 stones (59.6%) in 18 (78.2%) patients. US was able to localize 31 stones (68.8%) in 21 kidneys (75%), and 3 stones (25%) in 11 ureters (27.2%). Spiral CT is very effective in the diagnosis of pediatric urolithiasis. Spiral CT is more efficient than US in imaging pediatric patients with symptoms and signs of urolithiasis, when KUB is inconclusive.

Female↗

PubMed2006

Endourologic management of pediatric urolithiasis: proposed clinical guidelines.

BACKGROUND AND PURPOSE: Pediatric urolithiasis can be managed with various endourologic techniques, which are challenging and demanding. With the availability of advanced minimally invasive techniques, one has to select the appropriate modality. We analyzed the results of various techniques selected prospectively on the basis of our guidelines for the management of pediatric urolithiasis. PATIENTS AND METHODS: We analyzed the results of percutaneous nephrolithotomy (PCNL), ureteroscopy (URS), and extracorporeal shockwave lithotripsy (SWL) in 45 children treated at our institute between January 2004 and May 2005. There were 35 boys and 10 girls ranging from 12 months to 17 years age (median age 8.2 +/- 5.72 years), with 25 children (55.6%) under the age of 8 years. Stone-free rate, complications, and hospital stay were assessed. RESULTS: Extracorporeal lithotripsy was performed in 13 children (15 renal units) with average stone surface area of 50.8 +/- 35.8 mm(2). The stone-free rate was 92.3%. The total number of shocks per treatment ranged from 450 to 1400 (mean 856.3 +/- 189.6). A total of 25 PCNLs were done. Stone extraction was completed in a single stage in 20 units (80%), whereas 5 units (20%) required a second stage. Stone-free status was achieved in 23 renal units (95.8%). In the URS group, 9 procedures were planned in 8 children, and rigid ureteroscopy was successful in 6 (66.7%). CONCLUSIONS: With the availability of various alternative approaches, proper treatment planning and judicious use of minimally invasive techniques can cure most patients. On the basis of our experience and results, we recommend an algorithm for the management of pediatric stone disease.

Adolescent↗

PubMed2006

Pediatric urolithiasis: etiology, specific pathogenesis and medical treatment.

Pediatric urolithiasis is an endemic disease in certain parts of the world, namely Turkey and the Far East. As a recurrent pathology which may reveal functional as well and morphologic changes in the urinary tract, environmental factors together with urogenital abnormalities should be evaluated thoroughly in each patient. The aims of management should be complete clearance of stones, treatment of urinary tract infections, preservation of renal function and prevention of stone recurrence. In addition to certain minimally invasive stone removal procedures, treatment of pediatric urolithiasis requires a detailed metabolic evaluation in all patients on an individual basis. Obstructive pathologies have to be corrected immediately and children with a positive family history should be followed carefully with respect to a high likelihood of stone re-growth and recurrence. Although specific management of each metabolic abnormality seems to be the key factor in the medical management of stone disease, as general advice each child should be forced to adequate fluid intake which will reveal the urine volume increase in accordance with the body mass index. Moreover, medical therapeutic agents which increase urine citrate levels should be encouraged.

Child↗

PubMed2005

Diagnosis of pediatric urolithiasis: role of ultrasound and computerized tomography.

PURPOSE: Pediatric urolithiasis is believed to be uncommon, and may present without the classic symptoms of renal colic. The objectives of this study were to describe the presenting features and radiographic evaluation of pediatric urolithiasis, and to determine the accuracy of ultrasound and unenhanced computerized tomography (CT) in detecting urolithiasis. MATERIALS AND METHODS: We retrospectively reviewed the charts of children 0 to 18 years old with urolithiasis. Data collected included age, sex, race, presenting symptoms, radiographic studies performed during initial evaluation, calculus location and family history of urolithiasis. RESULTS: A total of 75 patients had complete data for analysis. Of these patients 54 (72%) had urolithiasis symptoms (flank pain, gross hematuria or both). Patients with urolithiasis symptoms were older at diagnosis (median age 11.9 years vs 1.0 years, p <0.001) and were more likely to have a family history of urolithiasis (54% vs 14%, p = 0.002). The 39 CTs performed were accurate in detecting calculi in children with urolithiasis symptoms (96% to 100%) and in those without symptoms (100%). The 36 ultrasounds performed had more variable accuracy in children with urolithiasis symptoms (33% to 100%) vs those without symptoms (89%). Ultrasound failed to detect urolithiasis in 41% of the patients with urolithiasis symptoms, compared to 5% with CT. CT was also highly accurate regardless of calculus location (89% to 100%), whereas ultrasound was again more variable (kidney 90%, kidney and ureter 75%, ureter alone 38%). CONCLUSIONS: Ultrasound failed to detect calculi in 41% of the children with urolithiasis symptoms, whereas CT was highly accurate in all situations. Unenhanced CT should be performed in all children with persistent urolithiasis symptoms and nondiagnostic ultrasound.

Adolescent↗

PubMed2003

Pediatric urolithiasis--evaluation of risk factors in 95 children.

OBJECTIVE: Pediatric urolithiasis is a rarely encountered pathology, except in endemic areas such as Turkey. As a recurrent pathology which may reveal functional as well and morphologic changes in the urinary tract, metabolic and environmental factors, in addition to urogenital abnormalities, should be evaluated thoroughly in each patient. In this prospective study, the patient and family histories of 95 children with stone disease were evaluated, together with serum and urine risk factors. MATERIAL AND METHODS: Between 1996 and 2001, 95 children (25 females, 70 males; mean age 7.3 years; age range 0.6-15 years) referred to our department with urolithiasis were evaluated. All patients were investigated with respect to stone localization, associated abnormalities, urinary tract infection (UTI), positive family history and serum and urine risk factors. In addition to standard risk factors (hypocitraturia, hypercalciuria, hyperoxaluria, hyperuricosuria, hypomagnesuria), diet and 24-h urine volume were also assessed in all children. Children with cystinuria were excluded from the study. RESULTS: Stone size ranged from 0.3 to 3.3 cm, with an average value of 2.0 cm. The localization of the stones was classified as unilateral single stone in 37 patients, multiple unilateral stones in six and bilateral multiple stones in 27. Hypocitraturia was the commonest risk factor detected in our patients. A positive family history was present in 51 cases (54%). In addition, UTI was present in 59 cases (62%) and 67 cases had a previous history of recurrent UTI. Associated urogenital abnormality was detected in nine cases (9.4%). There were significant correlations between stone size and urinary citrate excretion (p < 0.05) and between the presence of UTI and urinary phosphate excretion (r = 0.59, p = 0.047). Treatments used were open surgery in seven (7.3%) cases, extracorporeal shock-wave lithotripsy in 39 (41%) and endoscopic surgery in 20 (21%). Following these procedures, 39 (41%) patients were completely stone-free, 11 (11%) had residual stones (<5 mm in diameter) and 12 (14.8%) passed the stone(s) spontaneously. During follow-up, regrowth was seen in four (4.2%) patients and stone recurrence was noted in a further four (4.2%). CONCLUSIONS: In addition to stone removal, treatment of pediatric urolithiasis requires a thorough metabolic and environmental evaluation of all patients on an individual basis. Obstructive pathologies have to be corrected immediately and apparent metabolic abnormalities should also be treated. Children with a positive family history should be followed carefully with respect to stone recurrence. Urine volume increases in parallel with body mass index and medical therapeutic agents which increase urine citrate levels should be encouraged.

Adolescent↗

PubMed1996

Treatment of pediatric urolithiasis between 1984 and 1994.

PURPOSE: We report our experience with the management of pediatric urolithiasis during a 10-year period. Our aim was to assess the impact of new technology in the treatment of pediatric urolithiasis. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients up to age 18 years in whom urolithiasis was treated from 1984 to 1994. In 37 cases 24-hour urine collections were available for metabolic evaluation. RESULTS: A total of 100 pediatric patients was treated for urolithiasis. Mean followup was 36 months. A total of 79 patients underwent 115 procedures for symptomatic urolithiasis and 21 were treated nonoperatively. In 42 patients structural anomalies of the urinary tract required additional management. Metabolic abnormalities in 48 patients included hypercalciuria in 19, defined as greater than 4 mg./kg./24 hours calcium by 24-hour urine collection. Only 24 of the 100 patients had no identifiable predisposing factors. Procedures included shock wave lithotripsy in 42 cases, basket extraction with or without ureteroscopy in 20, percutaneous nephrostolithotomy in 11 and litholapaxy in 12. Open surgery included cystolithotomy in 10 cases and other forms of open lithotomy in 15. Thus, open surgical removal was necessary in 1 of 5 cases. CONCLUSIONS: Compared to the traditional mode of stone treatment, fewer patients required open surgery. Our results indicate that a comprehensive approach to the care of pediatric patients with urolithiasis requires attention to metabolic and structural abnormalities.

Adolescent↗

PubMed1999

Possible causes for the low prevalence of pediatric urolithiasis.

OBJECTIVES: To determine why the incidence of pediatric urolithiasis is less than that of adult urolithiasis, we investigated the difference in inhibition of calcium oxalate (CaOX) crystallization between pediatric and adult urinary macromolecules (UMMs). METHODS: Urinary parameters in relation to urolithiasis, the inhibition of CaOX crystallization of original urine and urine from which UMMs (greater than 3 kDa) had been removed, and the inhibition of CaOX crystal growth and aggregation of UMMs alone were measured. These inhibitory activities were compared between children and adults. RESULTS: In the original urine, the inhibition of CaOX crystallization was significantly stronger for children than for adults, but was the same in urine from which the UMMs had been removed. The inhibition of CaOX crystal growth by UMMs alone showed no significant differences between children and adults; their inhibition of CaOX crystal aggregation was significantly stronger for children than for adults. Much more glycosaminoglycan (GAG) was included in pediatric UMMs than in adult UMMs, although there was no difference in UMM concentration between urine from children and urine from adults. CONCLUSIONS: The lower incidence of CaOX lithiasis in children may be attributed, among other factors, to the stronger inhibition of CaOX crystal aggregation by pediatric UMMs, which in turn might be affected by the higher concentration of GAGs in children's urine.

Adolescent↗

PubMed2004

Endoscopic management of pediatric urolithiasis in a developing country.

OBJECTIVES: To evaluate our experience with the endoscopic management of lower and upper urinary tract stones in pediatric patients in the Republic of Yemen. METHODS: From January 1, 1993 to December 31, 1998, 290 endoscopic operations were performed on 265 pediatric patients up to 14 years of age, 173 on the upper and 117 on the lower urinary tract. Of these procedures, 138 were percutaneous nephrolithotomy, 5 were endopyelotomy combined with percutaneous nephrolithotomy, 30 were ureteral lithotripsy, and 117 were percutaneous cystolithotomy. Of the 265 patients, 244 were boys and 21 girls (male/female ratio 11.6:1, upper tract 7.4:1, lower tract 116:1) aged 8 months to 14 years (mean age 7.1 years). The 26F adult nephroscope and 9.5F semirigid ureteroscope were used. RESULTS: The overall success rate was 98.9%. Minor complications were observed in 29 patients (10.7%); severe complication did not occur. The nucleus and/or the main component of the stones was ammonium urate in 73.5% of the cases (upper tract 54%, but for those younger than 5 years, it was 75%; lower tract 93%). CONCLUSIONS: The endoscopic management of pediatric urolithiasis is a safe and effective method. To our knowledge, this is the largest reported series on the endoscopic management of pediatric urolithiasis.

Adolescent↗

PubMed1996

Endoscopic treatment of pediatric urolithiasis.

Children have been slow to benefit from the improvements in stone therapy. Despite the success of less invasive techniques, open surgery for pediatric urolithiasis is still commonly practiced. The authors' goal was to evaluate the indications, efficacy, and complications of endourologic surgery in the treatment of pediatric urolithiasis. They reviewed the treatment of 53 children who had upper tract calculi. Open nephro- and ureterolithotomy were avoided in all cases. The management of 25 children whose stones were not amenable to extracorporeal shock wave lithotriopsy is presented. Seventeen children (19 stones) were treated with miniature ureteroscopes and lasertripsy. Only one (6%) of the patients required ureteral dilation, and only five (29%) needed a postoperative internal stent. Eight children with large renal calculi were treated percutaneously, without transfusion, complication, or evidence of persistent renal damage. All 25 patients were rendered stone-free. The hospital stay was shorter and secondary procedures were less common in comparison to other series of endoscopic lithotripsy. With significant experience in adult endourology and proper instrumentation, one can apply the same techniques to children and achieve equal if not greater benefit. Nephrolithiasis in children is uncommon and should be managed in an institution where endourologists and multiple treatment modalities are available.

Adolescent↗

PubMed1999

Initial experience with endoscopic holmium laser lithotripsy for pediatric urolithiasis.

PURPOSE: Due to the unavailability of suitable pediatric instruments children have not benefited from advances in endoscopic lithotripsy. This limitation may be overcome by the holmium: YAG laser. We evaluated the indications for, and efficacy and complications of holmium:YAG laser lithotripsy. MATERIALS AND METHODS: We retrospectively reviewed all cases of laser lithotripsy. Access to the calculus was antegrade or retrograde. A solid state holmium:YAG laser was used. RESULTS: Eight patients 4 to 14 years old underwent laser lithotripsy during the study period. Average calculous surface area was 357.13 mm.2 (range 14 to 1,645). Five patients required 1 procedure to render them stone-free, while the remaining 3 required multiple procedures. No complications were associated with laser lithotripsy. CONCLUSIONS: The ability of the holmium:YAG laser to pulverize urinary calculi makes it an alternative choice for lithotripsy. In our series all patients are stone-free with stable renal function. The advantages of the holmium:YAG laser are that it may be precisely applied via small fibers, and it pulverizes calculi with minimal scattering of energy and retropulsion of the calculus, decreasing trauma to tissues at the perioperative site. There is also a lower risk of residual fragments, which is associated with a lower incidence of calculous regrowth. Holmium: YAG laser is safe and effective for treating pediatric urolithiasis.

Adolescent↗

PubMed2004

Results of shockwave lithotripsy for pediatric urolithiasis.

BACKGROUND AND PURPOSE: Shockwave lithotripsy (SWL) is widely practiced in the management of pediatric urolithiasis. However, the efficacy, need for ancillary procedures, and treatment-related complications are not as clearly defined as in the adult population. We reviewed the outcomes of SWL in the pediatric population at our lithotripsy unit. PATIENTS AND METHODS: A retrospective review of all patients </=16 years of age treated with SWL between January 1991 and June 2002 was undertaken. One hundred patients with 115 stones underwent 131 SWL procedures (115 first treatments, 16 retreatments). The mean age was 10.7 years (range 10 months-16 years). Stone locations were as follows: caliceal 42.6%, renal pelvic 27%, and ureteral (30.4%). The mean stone size was 7.8 mm (range 2-23 mm). Risk factors for stone formation, the need for secondary therapies, and treatment-related complications were noted. The stone-free rate for a single-session SWL procedure, defined as complete absence of stone fragments on plain film, intravenous urography, or renal ultrasonography, was calculated based on 3-month follow-up. The efficiency quotient (EQ) was also calculated. RESULTS: Risk factors were identified in 31 children (27.0%), including metabolic and anatomic abnormalities. Patients with a risk factor were less likely to be stone free after one SWL session than those without risk factors (31.7% v 64.7%; P < 0.001). General (74.8%), neurolept (24.4%), and epidural (0.8%) anesthesia were utilized. Ureteral stents were placed in 25% of treatments. There were no intraoperative complications. Minor complications were seen in 4.6% of patients. Ancillary procedures were required in 10 patients. Following initial SWL treatment, 60.2% of patients were stone free. The retreatment rate was 13.9%. Following a second treatment, the stone-free rate increased to 68%. The EQ was 54.3. CONCLUSION: Employing a strict definition of treatment success, single-session SWL in our series offers moderate efficacy in the pediatric population. Patients who have a large stone or risk factor such as an anatomic abnormality are less likely to become stone free and might better undergo an endourologic procedure.

Adolescent↗

PubMed2006

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.

Acute Disease↗

PubMed2003

Management of pediatric urolithiasis in Pakistan: experience with 1,440 children.

PURPOSE: We evaluated the efficacy and safety of different modalities for pediatric urolithiasis in a developing country in 2 eras, namely before and after the advent of minimally invasive surgery. MATERIALS AND METHODS: We retrospectively reviewed the records of 1,440 children younger than 14 years treated with various modalities during a 14-year period. From 1987 to 1995, 486 and 50 patients were treated with open surgery, and extracorporeal shock wave lithotripsy (ESWL, Dornier Medical Systems, Inc., Marietta, Georgia) and minimally invasive methods, respectively. Between 1996 and 2000, 518 and 386 children were treated with surgery and minimally invasive methods, respectively. RESULTS: Of the 1,440 children 795 (55.2%) had renal, 198 (13.8%) had ureteral and 447 (31%) had bladder calculi. Of the renal stones 556 (70%), 177 (22%) and 62 (7.8%) were treated with open surgery, ESWL and percutaneous nephrolithotomy, respectively. Of the ureteral calculi 85 (43%), 37 (18.6%) and 76 (38%) were managed by ESWL, ureterorenoscopy and open surgery, respectively. Of the bladder calculi 307 (68%), 77 (17.2%) and 63 (14%) were treated with open vesicolithotomy, transurethral pneumatic cystolithotripsy and ESWL, respectively. The renal stone clearance rate was 98% after open surgery, 84% after ESWL and 68% after percutaneous nephrolithotomy monotherapy at 3 months of followup. Similarly the ureteral stone-free rate was 54% after ESWL and 86.9% after ureterorenoscopy. Of the patients with bladder calculi 48% and 93% become stone-free after ESWL and transurethral pneumatic cystolithotripsy, respectively. CONCLUSIONS: The use of ESWL, percutaneous nephrolithotomy and ureterorenoscopy has resulted in treating a large number of children with a short hospital stay and early return to school. Open surgery is reserved only for complex stones.

Adolescent↗

PubMed2006

[Using of percutaneous nephrolithotomy in pediatric urolithiasis].

OBJECTIVE: To assess the safety and efficacy of percutaneous nephrolithotomy (PCNL) using ureteroscope and pneumatic intracorporeal lithotripsy in the pediatric age group. METHODS: Twenty-two renal units in 15 patients underwent PCNL at our institute. The patients were all under 14 years old. The average age was 9 years (range 5-14 years). There were 7 bilateral, 8 multiple, and 5 staghorn calculi. The average calculus size was 2.0 (0.9-4.5) cm. The PCNL was done with an X ray-guided peripheral puncture, a planned staged approach in some cases, and minimal tract dilatation with the use of an ureteroscope and pneumatic intracorporeal lithotripsy. RESULTS: Complete stone clearance was achieved in 20 renal units, giving an overall clearance rate of 91%. Minor pyrexia (< 39 degrees C, < 2 days) was seen in 14 patients, whereas serious pyrexia was seen in 1. The average fall in hemoglobin was 10 g/L, but none of the patients required blood transfusion. CONCLUSIONS: It is safe and effective to cure pediatric urolithiasis with percutaneous nephrolithotomy using ureteroscope and pneumatic intracorporeal and pneumatic intracorporeal lithotripsy.

Adolescent↗

PubMed2000

Characteristics of pediatric urolithiasis in south-east Anatolia.

BACKGROUND: Urolithiasis is endemic in Turkey and characteristics of urolithiasis vary in different regions of the world. The aim of the present study was to evaluate the etiological and clinical characteristics and course of pediatric urolithiasis in south-east Turkey. METHODS: The study population consisted of 81 children (52 girls) with urolithiasis at a mean age of 6.2 +/- 4.2 years who were followed up for 1-32 months. RESULTS: Metabolic disorders, anatomical defects and infection stones were found to be the etiological factor in 34.6, 29.6 and 22.2% of patients, respectively, while 13.6% of patients were considered idiopathic. Of all patients, 28.4% were admitted with acute renal failure (ARF) and 72.8% had urinary tract infection. Recurrence was seen in 19.8% of patients at presentation. The localization of the stone was found to be in the upper urinary tract, the lower urinary tract or both in 65.4, 14.8% and 17.3% of patients, respectively. Patients with multiple and bilateral stones had a higher risk for ARF than the others. The risk for chronic renal failure was significantly higher in children with multiple, bilateral or recurrent stones and with ARF at presentation. CONCLUSIONS: Early diagnosis and management of renal stones and urinary tract infections is necessary to prevent the development of ARF or chronic renal failure and to improve the quality of a patient's life.

Acute Kidney Injury↗

PubMed2001

Pediatric urolithiasis.

Urinary lithiasis in the pediatric population has evolved from a mere clinical curiosity to a disease process worthy of thoughtful and rigorous scientific study. All aspects of urinary lithiasis have undergone this evolution, including the epidemiology of stone formation in children, defining new modalities of radiologic imaging, and refining surgical techniques for stone treatment. These advancements and observations in pediatric stone disease are highlighted.

Child↗

PubMed2000

Pediatric urolithiasis in sub-saharan Africa: a comparative study in two regions of Cameroon.

OBJECTIVE: To determine the composition of caculi and the predisposing factors for stone nucleation and growth in children from two regions of Cameroon. METHODS: This was a cross-sectional study involving 21 children, 17 from the northern and 4 from the southern region, over a 6-year period. Data on age, diet, residence, clinical presentation, location of stone, and results of stone analysis were collated following a preestablished proforma. A computerized analysis of the data was carried out. The constituents of stone sections and nidus were assembled so as to determine the principal causes of stone nucleation and growth. RESULTS: Pediatric urolithiasis was more common in the northern Sahelian belt of Cameroon. Males and rural dwellers were more commonly affected. Endemic (bladder) stone disease was found in the majority of the patients. All stones were mixed. The most frequent constituents of the stones were ammonium urate, struvites, and whewellite in descending order of percentage mean volume per stone. The nidus was available for study in only 10 stones, and its composition revealed heterogeneity of causes of nucleation. The commonest cause for stone formation and growth were infection and hyperuricosuria (malnutrition). CONCLUSIONS: Pediatric bladder stone disease is not uncommon in northern Cameroon. Many factors combined to predispose to stone nucleation and growth, but the level of socioeconomic development was preponderant. Stone composition indicated that urolithiasis in children was a heterogeneous disorder, but hyperuricosuria, insufficient diuresis, and infection associated with malnutrition seemed to be the most common causes.

Adolescent↗