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PubMedDate not supplied

[Genetic aspects of urolithiasis in children].

Genetic aspects are essential in genesis of urolithiasis. We have collected information on 3064 relatives of probands (1209 males, 2395 females). Genealogical analysis in the families of children with urolithiasis and in 30 control families (392 females, 211 males) was performed. Urolithiasis occurred in 15.7% of fathers, 20.4% of mothers of the probands and 3.3% of fathers of the control group. Occurrence of urolithiasis in parents of urolithiasis children was 10.7 times that of the controls and reached 36.1%. In probands' sibs urolithiasis was encountered in 28%. The number of risk factors correlated with probability of urolithiasis development.

Age Factors↗

PubMedDate not supplied

[Evaluation of treatment and preventive care for recurrent urolithiasis in children].

Among 425 children with urolithiasis treated in the Paediatric Clinical Department of the National Research Institute of Mother and Child in Warsaw between 1976-1997, 50 of them i.e. 11.7% (26 boys and 24 girls) had recurrent urolithiasis. Patients' age was from 10 months to 16 years and 5 months. The number of recurrences of uroliothiasis before treatment in the Institute was from 1 to 8. Most of the children had numerous surgical operations, some of them excreted stones spontaneously. The etiology was determined in all cases. A metabolic cause of urolithiasis was found in 34 cases, i.e. 68% of the analysed group. They were as follows: idiopathic hypercalcuria--24 cases, uric acid urolithiasis--5 cases, cystynuria--4 cases, and incomplete distal renal tubular acidosis--1 case. Other reasons for urolithiasis were: infection--7 cases, idiopathic urolithiasis--8 cases, ren spongiosum--1 case. Prevention of recurrences depending on the etiology was successful. In 45 cases no recurrences were found. Recurrent urolithiasis was observed in 4 cases of cystynuria and in one case of incomplete tubular acidosis. The observation period was from 3-19 years.

Adolescent↗

PubMed2002

[Clinico-epidemiologic study of urolithiasis in a Caribbean urban area].

Urolithiasis is a common clinical disorder. Its frequency has risen with the development of humanity and varies wirl the country, geographic area, etc. It poses health problems in most countries. The urolithiasis has some potential risk factors such as intrinsic and extrinsic epidemiological, metabolic, physic-chemistry of the urine, mechanics and urinary infection. Our objective in this epidemiological study in a general population was to know the frequency, the potential risk factors, the morbidity, and social and economical impact of the urolithiasis in our subtropical Caribbean country. The prevalence was 4.64% and the annual incidence was 0.1%. Both are with in the estimated range of urolithiasis frequency in the world. It mainly started between 20 and 29 years in both genders. The white (5.2%) and the male (6.36%) patients were the most affected. 40% of all patients had a family history of urolithiasis. It was highly associated with diabetes mellitus, ischaemic cardiopathy, urinary tract infection and arterial hypertension. Stone formation was related to the warmer season. High calcium, protein-purine, carbohydrates and oxalic acid intake together with low fluid intake were closely associated with this disorder. 85% of patients had suffered renal colic and 75% of them more than once. Stone recurrence affected 33.8% of patients and 54.5% of them had more than one recurrence. Procedures for stone removal were needed in 33.8% of subjects. 40% of all patients were admitted to hospital due to urolithiasis morbidity. Non-specific medical treatment had been taken by 49.2% of the patients and specific treatment by none. Urolithiasis in this population was the some as has been reported in others studies. It has shown high frequency, increasing incidence, the same risks factors, high morbidity, and high social and economical impact. The low cost treatment is only taken by half of the patients.

Adolescent↗

PubMed2005

Urolithiasis in rats consuming a dl bitartrate form of choline in a purified diet.

Urolithiasis appeared in rats maintained to study the effects of nutrients and methylmercury on development and aging. After a year, the mortality rate was approximately 10%, and by 2 years, it had increased to nearly 30%. Clinical signs and urinary tract pathology were examined as a function of diet, duration on diet, gender, methylmercury exposure, genetics, and other potential risk factors by using survival analyses and qualitative comparisons. Urolithiasis in female rats appeared 15 weeks after beginning a purified diet and after 5 weeks for male rats. After 97 weeks, the mortality rate of female rats was 22% and for male rats was 64%. Lifetime urolithiasis-associated mortality was about 2% in a group of rats that consumed the contaminated diet for < 30 weeks. No urolithiasis occurred in siblings or cohorts of the rats described here that were maintained on a standard rodent chow containing choline chloride. Urolithiasis was traced to racemic, rather than levo-, bitartaric acid in some purified diets shipped in 2001 and 2002. It is unknown when the impurity first appeared in the diet, so estimates of exposure duration are upper limits. Chronic methylmercury exposure increased vulnerability. Some families (dam + offspring) had multiple cases of urolithiasis, but probability models constructed to evaluate familial clustering revealed no evidence for a genetic predisposition to urolithiasis apart from gender. Removing racemic tartaric acid did not decrease mortality once rats had been on the diet for 20 to 30 weeks, but it helped when exposure duration was shorter.

Animal Feed↗

PubMed1986

Formation of calcium oxalate urolithiasis in experiment and its inhibition by pyridoxine and magnesium.

Possibility of application of experimental model of calcium oxalate urolithiasis to the study of some medicament actions useful in prevention of calcium oxalate urolithiasis in men has been examined in animal experiments. Inhibition effects of pyridoxine and magnesium in formation of calcium oxalate stone formation have been proved. Administration of pyridoxine and/or magnesium to experimental animals inhibited formation of incrustations on renal papillae. Administration of nothing but magnesium lowered considerably also frequency of nephrocalcinosis occurrence. Good reproducibility of applied model of calcium oxalate urolithiasis creates conditions for further experimental study of this kind of urolithiasis. In the previous series of experiments (4) we tiped out an experimental model of calcium oxalate urolithiasis in animals well reproducible in our conditions. In the following period we were interested, whether the created model can be applied to verification of efficiency and further study of some medicaments affecting this kind of urolithiasis. At present, pyridoxine and magnesium are mode widely used for prevention of calcium oxalate urolithiasis in the clinical practice. Therefore, we decided to use the possibilities of the evaluated experimental model for the study of their inhibition effects. The results of experiments are presented in this paper.

Animals↗

PubMedDate not supplied

[The characteristics of calculus formation in the kidneys of patients in families predisposed to urolithiasis].

To specify the implication of the genetic factors in formal genesis of urolithiasis, the pattern of stone formation was investigated in 206 probands with urolithiasis hereditary loading versus 324 patients rejecting family history of this disease. Distribution of the disease forms was considered in correlation with mineral metabolism derangement and hereditary loading in the proband. It was found that severe urolithiasis occurs more frequently in the groups with phosphorus-calcium urolithiasis. These groups also included many families with the disease history. Numerous cases of urolithiasis of hyperparathyroidism etiology suggest endocrine disorders involvement in urolithiasis onset. Clarification of hereditary loading and its distribution in the families of urolithiasis patients allows a purposeful control of the families members to render them prophylactic aid.

Adolescent↗

PubMed1997

[Personal experience in the diagnosis and monitoring of therapy in metabolic disorders with risk of crystallization in patients with recurrent urolithiasis].

A ten-year experience with diagnosis and therapy of metabolic abnormalities and crystallization risks in patients with recurrent urolithiasis is presented. Since 1985, more than 900 persons with recurrent urolithiasis have been examined at the Metabolic Centre of the Hospital in Sternberk. The patients were examined routinely at ambulance or during hospitalization; the examination consisted of repeated urine and blood collections after the diet with various content of calcium and salt. All initial data (case history, physical finding, biochemistry, radiodiagnostics) were processed by a semi-expert computing program SOFT which was also used for monitoring of the therapy. Then the patients were divided into individual risk groups (Pak). Of all probands, the group of 130 patients (satisfying the strict criteria of the study) was selected and the data obtained was processed statistically. The group of 130 patients with recurrent urolithiasis (all of them were drug-treated) was compared to the group of 50 individuals with urolithiasis treated by diet and regimen measures. The patients given drugs showed a significantly increased crystallization inhibitors concentration in urine and reduced crystallization promotors, or relative saturation of some lithiatic substances. The paper analyzes the effect of the mostly administered drugs on crystallization risks and some less known "metabolic" indications of application of some drugs are recommended. It is concluded that the dietary, drinking and regime measures are basic for a good therapy of patients with urolithiasis, but patients with recurrent urolithiasis should be applied a selective metaphylaxis of drugs after routine metabolic examination. This finding is supported by a low number of recurrent urolithiasis.

Adult↗

PubMed2006

Vitamin D receptor gene polymorphisms in patients with urolithiasis.

Urolithiasis is a multifactorial disease, the onset and severity of which is influenced by both genetic and environmental factors. This study represents an investigation of the role of vitamin D receptor (VDR) gene polymorphisms (ApaI, BsmI, and TaqI) and combined genotypes in urolithiasis in a Turkish population. We studied 110 patients with urinary stones and 150 control subjects. The polymorphic regions were amplified using polymerase chain reaction, followed by digestion with restriction enzymes BsmI, ApaI, and TaqI, and analyzed electrophoretically. Genotype and allele frequencies were calculated, and the association with urolithiasis, family history, and recurrence of stone was investigated. Our data provide no evidence for an association between urolithiasis and VDR ApaI, BsmI, and TaqI genotypes. We also analyzed the effects of VDR ApaI, BsmI, and TaqI genotypes in combination; the "GTT" VDR haplotype, constructed from three adjacent restriction fragment length polymorphisms was overrepresented among the urolithiasis patients. However, no significant differences between heterozygous carriers (OR 1.302; 95% CI 0.527-3.215) and homozygous carriers (OR 3.39; 95% CI 0.719-15.985) were observed in our study population. A significant association was found only between the ApaI polymorphism and family history (P=0.017; chi (2)=5.657). Our data indicate that the VDR ApaI, BsmI, and TaqI polymorphisms do not confer a significant risk for urolithiasis.

Adolescent↗

PubMed2005

Bone and stone in ankylosing spondylitis: osteoporosis and urolithiasis.

Ankylosing spondylitis (AS) has well-defined renal complications, but urolithiasis has not been studied in detail. We aimed to evaluate the relation between AS and urolithiasis presence and the effect of this coexistence on the bone mineral status of patients. By dual-energy x-ray absorptiometry measurements at the femoral neck and lumbar vertebrae, we assessed the influence of urolithiasis, disease activity, and duration on bone mineral density (BMD) at different sites. Fifty-three AS patients and 25 control subjects were enrolled in the study. Mean age was 39.49+/-13.01 years for the AS group and 43.80+/-10.69 years for the control group, with no statistically significant difference. Patients were accepted as having active disease if two of the following were present: (1) symptomatic peripheral arthritis, (2) erythrocyte sedimentation rate greater than 30 mm/h, (3) C-reactive protein greater than 5 mg/L, and (4) dorsal-lumbar morning stiffness more than 60 min. The ratios of urinary stone presence were 11.32 and 12% for AS and control groups, respectively. We observed that a statistically significant difference in femur neck BMD between AS patients with or without urolithiasis was apparent. The lumbar BMD values were also lower in the urolithiasis subgroup but could not reach the statistical significance. There were no significant BMD alterations in the control group due to stone presence. Comparison of active-inactive disease groups revealed significantly low T scores in either the femur neck or L2-4 regions of patients with higher activity indices, but this difference was more prominent in the femur neck. In the early AS group (23 patients), 18 patients (78.26%) had L2-4 T scores lower than -1 SD, and in the advanced AS population, 19 of 30 patients (63.33%) had either osteopenia or osteoporosis (OP). We conclude that severe disease and concomitant urolithiasis might increase bone loss and fracture risk especially at the femur neck.

Absorptiometry, Photon↗

PubMed1989

Uric acid excretion in children with urolithiasis.

Urinary uric acid excretion was assessed in 38 children to determine whether hyperuricuria was a risk factor in children with urolithiasis. Uric acid excretion (measured per deciliter glomerular filtration rate), and fractional excretion of uric acid were similar in 27 children with hypercalciuria and calcium oxalate urinary stones, in six children with idiopathic calcium oxalate urolithiasis, and in five with uric acid urolithiasis, of whom four were white boys and one was an Asian girl. One boy with a urate stone had cystinosis. Serum uric acid concentrations exceeded 6.0 mg/dl (360 mumol/L) in two children with hypercalciuria and in two patients with idiopathic calcium oxalate urolithiasis. None of the children with calcium urolithiasis had excessive urinary excretion of uric acid. In children with hypercalciuria, uric acid excretion did not change significantly when dietary sodium was increased from 1.0 to 5.0 gm/1.73 m2. We conclude that excessive urinary uric acid excretion is seldom an additional risk factor in children with calcium urolithiasis and that dietary sodium chloride does not have a strong influence on urinary excretion of uric acid in children with hypercalciuria.

Adolescent↗

PubMedDate not supplied

Value of the urinary stone promoters/inhibitors ratios in the estimation of the risk of urolithiasis.

An imbalance between urinary-promoting and -inhibiting factors has been suggested as more important in urinary stone formation than a disturbance of any single substance. To investigate the value of promoter/inhibitor ratios for estimation of the risk of urolithiasis, urinary citrate/calcium, magnesium/calcium oxalate, and oxalate/citrate x glycosaminoglycans ratios were determined in 30 children with urolithiasis, 36 children with isolated hematuria, and 15 healthy control children. The cutoff points between normal children and children with urolithiasis, accuracy, specificity, and sensitivity for each ratio were determined and compared with those of the 24-h urine calcium and oxalate excretion and urine saturation calculated with the computer program EQUIL 2. The neural network application (aiNET Artificial Neural Network, version 1.25) was used for the determination of the cutoff points for the classification of normal children and the urolithiasis group. The best test for differentiating stone formers from non-stone formers proved the aiNET determined cutoff values of oxalate/citrate x glycosaminoglycans ratio. The method showed 97.78% accuracy, 100% sensitivity, and 93.33% specificity. Two cutoff points between normal and urolithiasis groups were found showing that the children with urolithiasis had ratio values either above 34.00 or less than 10.16. Increased oxalate excretion was linked to the first cutoff value (34.00), and decreased glycosaminoglycans excretion was typical of the second cutoff value (10.16).

Calcium↗

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↗

PubMed1996

Prevalence of urolithiasis in Kaizuka City, Japan--an epidemiologic study of urinary stones.

BACKGROUND: According to the results of nationwide surveys, the prevalence of urolithiasis has been steadily increasing in Japan. However, these surveys relied on hospital statistics, and there has been no survey of the prevalence of urolithiasis in Japan utilizing postal questionnaires. We surveyed the prevalence of urolithiasis among the inhabitants of Kaizuka City. METHODS: A total of 3,000 inhabitants ranging from 20 to 59 years old were randomly selected from the census register in numbers consistent with the population distribution of each district and sex by municipal computerized system. RESULTS: A total of 1,975 postal questionnaires were returned, and 1,972 (65.7%) were considered valid. Of the respondents, 137 (6.95%) had a history of stones (men; 9.64%, women; 4.51%). The annual incidence of urolithiasis for Kaizuka citizens aged from 20 to 59 years old in 1991 was 0.97%, and the lifetime prevalence of urolithiasis increased linearly with age, and it was 10.3% for respondents in their 50s. In the total survey population of 7,568, which included the respondents and their family members, 342 (4.52%) had a history of stones. Male administrative workers had a significantly higher prevalence than any other occupational group. The monthly expenditure on food by the families of stone formers was significantly greater than that by the families of non-stone formers. CONCLUSION: Extrapolation of the findings suggests that > 10% of the general population (> 13% of men and > 7% of women) can be expected to suffer from urolithiasis at least once in their lifetime.

Adult↗

PubMed1991

[The frequency and mechanisms of urolithiasis in acromegaly].

It is generally accepted that acromegaly is often associated with hypercalciuria, but there are few reports on the frequency and the mechanisms of urolithiasis. Recently we consecutively experienced 2 cases of acromegaly with urolithiasis, and these experiences made us investigate the association between urolithiasis and acromegaly. Among 18 acromegalies from 1977 to March 1990 (10 males, 8 females, 24-64 years old), 13 cases (72%) fulfilled the criteria of hypercalciuria (urinary calcium (u-Ca) greater than or equal to 200 mg/day or u-Ca/urinary creatinine (u-Ca/u-Cr) greater than or equal to 0.15), and 7 cases (39%) suffered from urolithiasis that was diagnosed by KUB (4 cases) or X-ray computed tomography (CT) (3 cases). Especially in the last 2 years, 5 out of 7 cases (71%) were complicated with urolithiasis and all 7 cases were associated with hypercalciuria. These results suggest that hypercalciuria and urolithiasis are both much more frequent than previously reported. In 6 cases who were treated by pituitary adenomectomy from 1988-1989 (4 males, 2 females, 24-59 years old), we examined Ca metabolism before and after operation. Before operation, the levels of serum growth hormone (GH), u-Ca (mg/day), u-Ca/u-Cr (in all cases) and plasma somatomedin-C (Sm-C) (in 4 cases) were increased above the normal range. To determine the etiology of hypercalciuria, we performed the oral Ca load test under restriction of Ca (400 mg/day) and P (650 mg/day) intake. The results suggested that the hypercalciuria might be mainly due to the increased absorption of Ca from the intestine (so-called "Absorptive hypercalciuria"). However, the levels of serum vitamin D (Vit. D) metabolites were all within the normal range before operation. After operation, GH and u-Ca/u-Cr (in 5 cases) and u-Ca (mg/day) (in all cases) decreased significantly compared with before operation, and the levels of Sm-C (in all cases), serum 25-(OH)D3, 1 alpha, 25-(OH)2D3 (in 4 cases) and 24,25-(OH)2D3 (in 3 cases) were also reduced after operation. Surprisingly, u-Ca and u-Ca/u-Cr normalized only in 4 cases who showed a reduction in 1 alpha, 25-(OH)2D3 levels after operation, although there were no correlations between u-Ca (mg/day) or u-Ca/u-Cr and 1 alpha, 25-(OH)2D3. Significant correlations were found between u-Ca (mg/day) or u-Ca/u-Cr and Sm-C. The parathyroid function evaluated by the rapid Ca infusion test or nephrogenous cyclic adenosine monophosphate (NcAMP) was normal before and after operation.(ABSTRACT TRUNCATED AT 400 WORDS)

Acromegaly↗

PubMed1989

Oxalate measurement in the picomol range by ion chromatography: values in fasting plasma and urine of controls and patients with idiopathic calcium urolithiasis.

Oxalate was measured by ion chromatography in the ultrafiltrate of heparinized plasma from peripheral venous blood, using a membrane with a cut-off molecular weight (Mr). The following criteria were established: sensitivity 0.7 mumol.l-1; intra- and inter-assay coefficients of variation 4% and 12%, respectively; precision of duplicate determinations (expressed as standard deviation) 0.08 mumol.l-1; overall recovery (oxalate added and diluted, respectively) 100.7%. These qualified the method for assessment of plasma oxalate in healthy human controls (males: n = 12) as well as patients with idiopathic renal calcium urolithiasis (males: n = 22; females: n = 16). Renal calcium urolithiasis patients were subclassified into those with normocalciuria and idiopathic hypercalciuria. In male and female controls the mean values (and range) of plasma oxalate were 1.98 (1.4-2.5) and 1.78 (0.7-2.9) mumol.l-1, respectively. In male controls ultrafiltration (membrane cut off Mr 10,000) revealed that 11-16% plasma oxalate was bound to constituents having an apparent Mr above 10,000, and that with use of membranes with smaller pore size, the ultrafilterability of oxalate decreases further. In renal calcium urolithiasis the following values were elicited (mumol.l-1): male normocalciuria 1.78 (0.8-4.0), idiopathic hypercalciuria 1.58 (1.2-2.2); female normocalciuria 1.69 (0.8-3.6), idiopathic hypercalciuria 1.21 (0.8-2.1). The difference from controls is significant in idiopathic hypercalciuria (males and females). In contrast, in fasting urine of renal calcium urolithiasis the oxalate excretion rate (5-45 mumol per 120 min) and oxalate clearance (21-328 ml per min) resemble those in controls, whereas in renal calcium urolithiasis the fractional oxalate clearance (30-357% of creatinine clearance) tended to higher values (p less than 0.01, in male idiopathic hypercalciuria versus controls). It is suggested that 1) ion chromatography allows the reliable assessment of ultrafiltrable plasma oxalate in health and disease states, 2) in renal calcium urolithiasis this technique may help to elucidate oxalate pathophysiology, especially the mode of renal handling of oxalate.

Adult↗

PubMed1978

Urolithiasis in chronic inflammatory bowel disease.

In a selected material of 228 patients with chronic inflammatory bowel disease (CIBD) the incidence of urolithiasis was 15% (95% confidence limit 11-21). The tendency to urolithiasis is significantly correlated to small-bowel resection and its extent and to obstruction in the urinary tract. On the other hand, there is no definite correlation to the duration or extent of the bowel disease. The significant correlation between urolithiasis and ileal resection is in agreement with the hyperabsorption of oxalate as an important cause of stone formation demonstrated by others. That local factors too play an essential role in the formation of urinary calculi is apparent from the increased incidence of urolithiasis in obstruction of the urinary tract. The incidence of urolithiasis was particularly high (22-25%) among patients with ileostomies. The few and negligible symptoms of and sequelae to, urolithiasis in CIBD encourage a conservative attitude.

Adolescent↗

PubMed1996

Idiopathic calcium oxalate urolithiasis and endogenous oxalate production.

Despite the great effort that has gone into investigating urolithiasis, this condition still persists as one of the major ailments of the urinary tract. Calcium oxalate urolithiasis is the most common form, accounting for some 60 to 80% of total stones. This review examines the elements (i.e., urine volume and pH and urinary excretion of calcium, oxalate, citrate, urate, magnesium, pyrophosphate, and glycosaminoglycans) that give rise to idiopathic calcium oxalate urolithiasis. Treatment strategies for idiopathic calcium oxalate urolithiasis, including lithotripsy, also are discussed. Urinary oxalate excretion is a major risk factor for calcium oxalate urolithiasis, with 85 to 95% of the urinary load derived endogenously. The factors controlling endogenous oxalate production are reviewed, including pathways for the diversion of glyoxylate from oxalate production. The use of beta-aminothiols and other substances to reduce endogenous oxalate production in subjects with idiopathic calcium oxalate urolithiasis is also discussed. A review of current methodologies for the determination of urinary oxalate is also included.

Animals↗

PubMed2004

The value of urine citrate/calcium ratio in the estimation of risk of urolithiasis.

The urine saturation is considered as the better parameter for the estimation of risk of urolithiasis than any single urinary constituent. However, the determination of urine saturation is unsuitable for routine clinical practice. To evaluate a simpler and cheaper test than urine saturation for distinguishing stone formers from healthy individuals, urinary citrate/calcium ratio was determined in 30 children with urolithiasis, 36 children with isolated hematuria, and 15 healthy control children. The ratio was significantly lower in urolithiasis group comparing to controls, and significantly higher in hematuria than in urolithiasis group. The cut-off points between normal children and children with urolithiasis, accuracy, specificity and sensitivity were determined and compared with those of the urine saturation calculated with the computer program EQUIL 2. The data mining Weka software was used for the determination of the cut-off points. Children with urolithiasis had citrate/calcium ratio below 1.38 and urine saturation above 5.285. The citrate/calcium ratio showed in comparison to urine saturation similar high accuracy (91.11 vs. 88.89%), somewhat lesser specificity (73.33% vs. 93.33%) and much better sensitivity (100% vs. 86.89%) in discrimination of stone formers from normal children. The advantage in comparison to urine saturation is that it can be easily performed in clinical practice.

Analysis of Variance↗