Association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria

The relationship between urinary tract infection caused by urease-producing bacteria and lithiasis due to struvite stones is well established in the literature. However, there is limited knowledge on whether non-urease producing bacteria can also promote crystallization. In our study, we analyzed the association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria, in 153 patients who underwent surgery for urinary stone. The collected samples were sent for crystallographic analysis and culture. Additionally, preoperatory urine culture was collected for combined evaluation with the previous data. Percutaneous nephrolithotomy was the most commonly performed approach (45.8%). Struvite stones were more frequently identified in women (90.3%). Among stones with positive cultures, except struvite, 45.5% were composed of calcium oxalate monohydrate. The difference between urine culture and stone culture was different in 24.8% of the cases. Among stones with positive cultures that did not contain struvite, 86.4% showed non-urease bacteria in their cultures and 47.1% of struvite stones also did not have urease-producing bacteria in their cultures (p < 0.021). Our findings suggest that there is an association between non-ureolytic bacteria and stones that are not composed of struvite.

[Bacteriological correlation of urinary stones and preoperative urine culture: Is there a significant impact on postoperative infectious risk? (Moroccan experience)]

AIM

The objectives of this study were to evaluate the impact of preoperative urine culture and the infected nature of stones on the occurrence of postoperative urinary sepsis.

MATERIAL AND METHODS

A prospective monocentric study included 29 patients operated on for urolithiasis between January and June 2018.

RESULTS

Postoperative urinary sepsis was observed in 4 patients (14%). Urinary colonization rate on preoperative CBU exam was 27.6% (8 of 29) while the rate of colonized stones was 31% (9 of 29). The occurrence of urinary sepsis was observed in 37.5% (3 of 8) of patients with urinary colonization, compared to 44.4% of patients with colonized stones (4 of 9). By comparing the bacteriological results observed during sepsis, the germs isolated in postoperative urine were the same found in the culture of stones. The chemical nature of the colonized stones was mainly calcium oxalate (monohydrate, dihydrate) P=0.02. There was a statistically significant correlation between the preoperative urine culture, the bacteriological culture of stones and the postoperative urinary sepsis (P=0.05, P=0.005) respectively.

CONCLUSION

Our study demonstrated a strong association between the bacteriological culture of stones and postoperative urinary sepsis superior to preoperative urine culture. It makes it possible to anticipate the occurrence of sepsis in patients requiring many endoscopic treatments. However, several multicentric prospective series may prove necessary to validate these results.

LEVEL OF EVIDENCE

3.

SEM-EDX linear scanning: a new tool for morpho-compositional analysis of growth bands in urinary stones

The genesis and growth of calculi are imprinted in their structure, so the pathogenesis of lithiasis could potentially be read via proper analytical techniques. In this study, electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) is used to obtain a description of the morphology and compositional structure of a single bladder stone. This technique establishes the chemical and crystalline architecture of the urolith to assess the effect of the chemical environment on its growth. Scanning electron microscopy-backscattered electrons (SEM-BSE) images clearly show that the stone has a multilayered structure. These layers and Liesegang ring-like structures are characterized by one predominant chemical component but also by slighter compositional changes. The mean crystalline components are determined by X-ray diffraction (DRX), infrared spectroscopy (FT-IR), and Raman analysis (RMN). Elemental analysis along a radial trajectory of the calculus by EDX linear scanning (EDX-LS) also reveals the compositional structure of the layers and the spatial distribution of the main chemical components. EDX-LS data processing reveals concentration profiles that clearly show morpho-compositional growth bands, which correspond to precipitation waves and urinary concentration peaks. The width of the growth bands is independent of the radial position, layer, and element analyzed. We conclude that the bands observed are a consequence of slight changes in the biochemical composition of the urine and consequently reflect a short-term biological cycle of the renal system. This non-specific growth rate suggests that stone formation is a kinetically controlled phenomenon in which promoters of crystal cluster aggregation may have played a key role.

SLIPS-LAB-A bioinspired bioanalysis system for metabolic evaluation of urinary stone disease

Urinary stone disease is among the most common medical conditions. Standard evaluation of urinary stone disease involves a metabolic workup of stone formers based on measurement of minerals and solutes excreted in 24-hour urine samples. Nevertheless, 24-hour urine testing is slow, expensive, and inconvenient for patients, which has hindered widespread adoption in clinical practice. Here, we demonstrate SLIPS-LAB (Slippery Liquid-Infused Porous Surface Laboratory), a droplet-based bioanalysis system, for rapid measurement of urinary stone-associated analytes. The ultra-repellent and antifouling properties of SLIPS, which is a biologically inspired surface technology, allow autonomous liquid handling and manipulation of physiological samples without complicated sample preparation procedures and supporting equipment. We pilot a study that examines key urinary analytes in clinical samples from patients with urinary stone. The simplicity and speed of SLIPS-LAB hold the potential to provide actionable diagnostic information for patients with urinary stone disease and rapid feedback for responses to dietary and pharmacologic treatments.

Identification of Amoxicillin Crystals in Urine: a Case Report

BACKGROUND

The case concerns a 30-year-old woman in the 24th week of pregnancy presenting to the medical emergency room with fever and abdominal pain. Urine sediment microscopy revealed the presence of unknown needle-shaped crystals.

METHODS

Crystals identification was performed by Fourier-Transform Infrared Spectroscopy coupled to Attenuated Total Reflectance (FTIR-ATR).

RESULTS

Amoxicillin crystals were verified with semiquantitative results of 87.7%.

CONCLUSIONS

Drug-induced crystalluria is a frequent finding in urine examination and it may be asymptomatic. FTIR spectroscopy is a rapid and specific tool in identification of crystals and could be useful supporting renal disease diagnosis and monitoring drug therapy.

The Impact of Glycosylation of Osteopontin on Urinary Stone Formation

Osteopontin (OPN) is a matrix glycoprotein of urinary calculi. This study aims to identify the role of aberrant glycosylation of OPN in urolithiasis. We retrospectively measured urinary glycosylated OPN normalized by urinary full-length-OPN levels in 110 urolithiasis patients and 157 healthy volunteers and 21 patients were prospectively longitudinal follow-up during stone treatment. The urinary full-length-OPN levels were measured using enzyme-linked immunosorbent assay and glycosylated OPN was measured using a lectin array and lectin blotting. The assays were evaluated using the area under the receiver operating characteristics curve to discriminate stone forming urolithiasis patients. In the retrospective cohort, urinary Gal3C-S lectin reactive- (Gal3C-S-) OPN/full-length-OPN, was significantly higher in the stone forming urolithiasis patients than in the healthy volunteers (p < 0.0001), with good discrimination (AUC, 0.953), 90% sensitivity, and 92% specificity. The Lycopersicon esculentum lectin analysis of urinary full-length-OPN showed that urinary full-length-OPN in stone forming urolithiasis patients had a polyLacNAc structure that was not observed in healthy volunteers. In the prospective longitudinal follow-up study, 92.8% of the stone-free urolithiasis group had Gal3C-S-OPN/full-length-OPN levels below the cutoff value after ureteroscopic lithotripsy (URS), whereas 71.4% of the residual-stone urolithiasis group did not show decreased levels after URS. Therefore, Gal3C-S-OPN/full-length-OPN levels could be used as a urolithiasis biomarker.

Prevalence of twenty-four hour urine testing in Veterans with urinary stone disease

OBJECTIVE

The American Urological Association guidelines recommend 24-hour urine testing in patients with urinary stone disease to decrease the risk of stone recurrence; however, national practice patterns for 24-hour urine testing are not well characterized. Our objective is to determine the prevalence of 24-hour urine testing in patients with urinary stone disease in the Veterans Health Administration and examine patient-specific and facility-level factors associated with 24-hour urine testing. Identifying variations in clinical practice can inform future quality improvement efforts in the management of urinary stone disease in integrated healthcare systems.

MATERIALS AND METHODS

We accessed national Veterans Health Administration data through the Corporate Data Warehouse (CDW), hosted by the Veterans Affairs Informatics and Computing Infrastructure (VINCI), to identify patients with urinary stone disease. We defined stone formers as Veterans with one inpatient ICD-9 code for kidney or ureteral stones, two or more outpatient ICD-9 codes for kidney or ureteral stones, or one or more CPT codes for kidney or ureteral stone procedures from 2007 through 2013. We defined a 24-hour urine test as a 24-hour collection for calcium, oxalate, citrate or sulfate. We used multivariable regression to assess demographic, geographic, and selected clinical factors associated with 24-hour urine testing.

RESULTS

We identified 130,489 Veterans with urinary stone disease; 19,288 (14.8%) underwent 24-hour urine testing. Patients who completed 24-hour urine testing were younger, had fewer comorbidities, and were more likely to be White. Utilization of 24-hour urine testing varied widely by geography and facility, the latter ranging from 1 to 40%.

CONCLUSIONS

Fewer than one in six patients with urinary stone disease complete 24-hour urine testing in the Veterans Health Administration. In addition, utilization of 24-hour urine testing varies widely by facility identifying a target area for improvement in the care of patients with urinary stone disease. Future efforts to increase utilization of 24-hour urine testing and improve clinician awareness of targeted approaches to stone prevention may be warranted to reduce the morbidity and cost of urinary stone disease.

[Clinical value of Canephron N after surgical treatment of urinary stone disease]

BACKGROUND

The drug Canephron N is a combination of extracts of centaury, lovage and rosemary. Moderate antispasmoic, anti-inflammatory, antioxidant, diuretic and antimicrobial effects are of great interest for urological practice. The optimal combination of components that were made of herbal medicine allows to use their synergistic effect for prevention of recurrence of urinary stone disease. The experience of using the drug Canephron in clinical practice is of great interest.

AIM

to clarify the clinical efficiency of Canephron N in patients with urinary stone disease after surgical treatment and to evaluate the changes in diuresis and calcium excretion.

MATERIALS AND METHODS

The results of using the drug Canephron after surgical treatment of urinary stone disease are provided. The changes in diuresis and calcium excretion in 75 patients undergone surgical treatment of urinary stone disease were studied. Patients after ureteroscopy, percutaneous nephrolithotomy and extracorporeal shock-wave lithotripsy were prescribed treatment to prevent stone formation including herbal drug Canephron N.

RESULTS

At baseline, there was negative correlation between 24-hours diuresis and calcium excretion in all groups. During follow-up, a positive correlation between 24-hours diuresis and calcium excretion was found in patients receiving Canephron N and other types of treatment. The average follow-up was 390 days. During this period, recurrence was noted in 1 patient receiving Canephron, 4 patients in patients who took other drugs and in 5 patients who didnt receive any treatment.

CONCLUSION

Risk factors of stone formation persist after surgical treatment of urinary stone disease. This is reflected in a negative correlation between 24-hour diuresis and calcium excretion. During treatment, a positive correlation between diuresis and calcium excretion was noted in patients with urinary stone disease. The use of drugs that affect stone formation as well as herbal medicine Canephron N allow to obtain comparable ratio of diuresis and calcium excretion.

A systematic review of the clinical significance of nephrostomy urine cultures

PURPOSE

There are few published reviews that have assessed the clinical utility of renal urine cultures following percutaneous nephrostomy (PCN). In this systematic review, we evaluated the published evidence of the clinical utility of nephrostomy urine cultures in the light of emerging antimicrobial resistance and need for stewardship.

METHODS

We performed a systematic literature search and review for evidence on the utility and role of nephrostomy urine cultures, using Medline, Embase and PubMed. We looked for evidence to assess whether there is any utility in collecting renal urine for culture at the time of percutaneous nephrostomy (PCN) and if the culture results of nephrostomy urine and bladder urine are different. We studied outcomes of treatment based on nephrostomy culture results. We also examined the role of PCN cultures at the time of routine nephrostomy exchange. Finally, we assessed if doing a PCN leads to infection or pyelonephritis.

RESULTS

From 94 studies initially identified, we finally selected two randomised clinical trials (RCT), six original articles and five detailed conference abstracts for the review. These studies suggest that PCN urine cultures are overall useful in clinical practice. They are useful in selecting appropriate antimicrobial treatment for urosepsis following upper urinary obstruction. There does not appear to be any advantage in performing PCN cultures at routine nephrostomy exchanges. Occasionally, PCN itself can lead to subsequent urosepsis.

CONCLUSION

Nephrostomy urine cultures have utility in clinical practice and can help support treatment and antimicrobial stewardship.

Reference intervals for stone risk factors in 24-h urine among healthy adults of the Han population in China

BACKGROUND

The aim of the study was to establish reference intervals for 24-h urinary stone risk factors in the healthy Chinese Han population.

METHODS

From May 2013 to July 2014, we collected and analyzed 24-h urine samples from healthy adult Han population during a cross-sectional study across China. The protocol for analysis of 24-h urine included volume, pH, oxalate, citrate, sodium, potassium, chloride, calcium, phosphorous, creatinine, urate, magnesium, the ion activity products of calcium oxalate (AP(CaOx) indexs) and calcium phosphate (AP(CaP) indexs). We calculated the reference intervals according to the Clinical and Laboratory Standards Institute (CLSI) 2008 guidelines and compared them with those recorded in other studies.

RESULTS

A total of 132 male and 123 female healthy subjects with a mean (SD, range) age of 52.4 (15.2, 19-89) years were eligible in the final analysis. Men had higher 24-h excretion of creatinine, calcium, urate and phosphorus and lower levels of citrate, magnesium, chloride, sodium and potassium than women. AP(CaOx) indexs and AP(CaP) indexs were significantly higher among men than women. When urinary findings were compared with the reference intervals, most of our data showed a high abnormality rate, especially for creatinine, calcium, citrate, magnesium, chloride, sodium and potassium.

CONCLUSIONS

The present study revealed the normal metabolic status for stone risk factors of the Chinese Han population. It is therefore necessary for each country or region to define their own reference intervals for comparison of stone risk factors between patients and healthy subjects.

Impact of Potassium Citrate vs Citric Acid on Urinary Stone Risk in Calcium Phosphate Stone Formers

PURPOSE

To our knowledge no medication has been shown to be effective for preventing recurrent calcium phosphate urinary stones. Potassium citrate may protect against calcium phosphate stones by enhancing urine citrate excretion and lowering urine calcium but it raises urine pH, which increases calcium phosphate saturation and may negate the beneficial effects. Citric acid can potentially raise urine citrate but not pH and, thus, it may be a useful countermeasure against calcium phosphate stones. We assessed whether these 2 agents could significantly alter urine composition and reduce calcium phosphate saturation.

MATERIALS AND METHODS

In a crossover metabolic study 13 recurrent calcium phosphate stone formers without hypercalciuria were evaluated at the end of 3, 1-week study phases during which they consumed a fixed metabolic diet and received assigned study medications, including citric acid 30 mEq twice daily, potassium citrate 20 mEq twice daily or matching placebo. We collected 24-hour urine specimens to perform urine chemistry studies and calculate calcium phosphate saturation indexes.

RESULTS

Urine parameters did not significantly differ between the citric acid and placebo phases. Potassium citrate significantly increased urine pH, potassium and citrate compared to citric acid and placebo (p <0.01) with a trend toward lower urine calcium (p = 0.062). Brushite saturation was increased by potassium citrate when calculated by the relative supersaturation ratio but not by the saturation index.

CONCLUSIONS

Citric acid at a dose of 60 mEq per day did not significantly alter urine composition in calcium phosphate stone formers. The long-term impact of potassium citrate on calcium phosphate stone recurrence needs to be studied further.

Do Urinary Cystine Parameters Predict Clinical Stone Activity?

PURPOSE

An accurate urinary predictor of stone recurrence would be clinically advantageous for patients with cystinuria. A proprietary assay (Litholink, Chicago, Illinois) measures cystine capacity as a potentially more reliable estimate of stone forming propensity. The recommended capacity level to prevent stone formation, which is greater than 150 mg/l, has not been directly correlated with clinical stone activity. We investigated the relationship between urinary cystine parameters and clinical stone activity.

MATERIALS AND METHODS

We prospectively followed 48 patients with cystinuria using 24-hour urine collections and serial imaging, and recorded stone activity. We compared cystine urinary parameters at times of stone activity with those obtained during periods of stone quiescence. We then performed correlation and ROC analysis to evaluate the performance of cystine parameters to predict stone activity.

RESULTS

During a median followup of 70.6 months (range 2.2 to 274.6) 85 stone events occurred which could be linked to a recent urine collection. Cystine capacity was significantly greater for quiescent urine than for stone event urine (mean ± SD 48 ± 107 vs -38 ± 163 mg/l, p <0.001). Cystine capacity significantly correlated inversely with stone activity (r = -0.29, p <0.001). Capacity also correlated highly negatively with supersaturation (r = -0.88, p <0.001) and concentration (r = -0.87, p <0.001). Using the suggested cutoff of greater than 150 mg/l had only 8.0% sensitivity to predict stone quiescence. Decreasing the cutoff to 90 mg/l or greater improved sensitivity to 25.2% while maintaining specificity at 90.9%.

CONCLUSIONS

Our results suggest that the target for capacity should be lower than previously advised.

Fourier Transform Infrared Analysis of Urinary Calculi and Metabolic Studies in a Group of Sicilian Children

INTRODUCTION

Prevalence of urinary calculi in children has been increasing in the past years. We performed an analysis of the chemical composition of stones formers of the pediatric population in our geographical area over the years 2005 to 2013.

MATERIALS AND METHODS

Fourier transform infrared spectroscopy was employed for the determination of the calculus composition of a group of Sicilian children, and metabolic studies were performed to formulate the correct diagnosis and establish therapy.

RESULTS

The prevalence of stone formation was much higher for boys than for girls, with a sex ratio of 1.9:1. The single most frequent component was found to be calcium oxalate monohydrate, and calcium oxalates (pure or mixed calculi) were the overall most frequent components. Calcium phosphates ranked 2nd for frequency, most often in mixed calculi, while urates ranked 3rd. The metabolic disorder most often associated with pure calcium oxalate monohydrate calculi was hypocitraturia, while hyperoxaluria was predominantly associated with calcium oxalate dihydrate calculi.

CONCLUSIONS

Mixed calculi had the highest prevalence in our pediatric population. Our data showed that Fourier transform infrared spectroscopy was a useful tool for the determination of the calculi composition.

Effect of Indapamide on Urinary Calcium Excretion in Patients with and without Urinary Stone Disease

BACKGROUND:

Indapamide is an antihypertensive agent similar to thiazides, but with some different effects. Thiazide and thiazide-like diuretics are useful in preventing recurrent urinary stone formation due to their hypocalciuric effects.

OBJECTIVE:

To determine the hypocalciuric and other effects on certain laboratory parameters of indapamide 1.5 mg in different patient groups.

METHODS:

Four groups of patients recruited from urology and nephrology outpatient departments were experiencing non-hypercalciuric urinary stone disease (group 1), idiopathic hypercalciuria (group 2), urinary stone disease with hypercalciuria (group 3), and essential hypertension (group 4). In all patients, fasting serum uric acid, calcium, sodium, potassium, cholesterol, triglyceride, parathyroid hormone (PTH) values, and morning second-spot urine calcium and creatinine levels were assessed before and 8 weeks after treatment with indapamide.

RESULTS:

Urinary calcium excretion was reduced significantly in all groups: group 1 from 0.10 ± 0.02 to 0.07 ± 0.03 (mean ± SD; 30% reduction; p < 0.001), group 2 from 0.30 ± 0.15 to 0.15 ± 0.10 (50% reduction; p < 0.001), group 3 from 0.35 ± 0.15 to 0.20 ± 0.10 (43% reduction; p < 0.001), and group 4 from 0.10 ± 0.03 to 0.08 ± 0.02 (20% reduction; p < 0.0010). These results should be interpreted with caution since no control group was included in this study. Mean serum uric acid and triglyceride levels were significantly increased, and mean PTH and potassium levels and diastolic and systolic blood pressure were significantly decreased in all groups. Few temporary adverse effects, such as dizziness and fatigue, were noticed and none of them caused discontinuation of treatment.

CONCLUSIONS:

Indapamide 1.5 mg/day is effective in decreasing calciuria in patients with non-hypercalciuric urinary stone disease, idiopathic hypercalciuria, urinary stone disease with hypercalciuria, and essential hypertension. This could be achieved with few adverse effects similar to those of thiazides and indapamide 2.5 mg. Indapamide decreased the PTH levels in all groups. Long-term clinical benefits of these effects should be evaluated prospectively with further randomized studies.

[Prospects for using biological markers in various types of urinary stone lithotripsy]

AIM

To investigate the feasibility of using biological markers for determining the optimal timing to repeat lithotripsy of urinary stones.

MATERIALS AND METHODS

This was a prospective, randomized, single-center cohort study of 100 patients randomized into 4 groups. Patients of group I (n=46), II (n=20), III (n=18) and IV (n=16) were used contact lithotripsy (URS), ESWL, PNL, combined lithotripsy. In all patients, before surgery and at 1, 7, 14, 20 days after lithotripsy, iron-induced urine chemiluminescence was measured to determine the level of reactive oxygen species (ROS) and concentration of medium-mass molecules (MMM) in urine.

RESULTS

Analyzing the time of operation and the size of stones only in group I was detected the significant negative correlation (r=-0,479, p<0,05). In patients of all groups, the level of ROS have decreased after the surgery with further returning to baseline level. Dynamics of changes MMM in urine has not revealed a reliable change tendency.

CONCLUSION

The definition of the quantity of ROS in urine is a promising criterion in measuring the degree of urinary system damage and the time for repeated lithotripsy. The level of ROS in the urine after URS, ESWL and the ESWL-URS combination returns to baseline on the 7th day and after PNL on the 14th day postoperatively, thus allowing to pathogenetically define the optimal timing of repeat lithotripsy.

[Cytological evaluation of urothelial damage in extracorporeal shock-wave lithotripsy]

INTRODUCTION

The study proposed a technique for early detection of the damaging effect of shock waves on the urinary tract tissues, for monitoring the state of urothelial cells in the early post-procedure period and choosing an adequate method for preventing and managing possible complications.

MATERIALS AND METHODS

The study analyzed the urine samples of 300 patients aged 20 to 50 years, who for the first time underwent ESWL for kidney stones. The urine sediment smears were fixed in the May-Grunwald stain and stained with azure eosin solution according to Pappenheim. Besides evaluating general cytologic characteristics, a morphometric examination of urine sediment was performed.

RESULTS AND DISCUSSION

To define quantitative parameters, the total number of epithelial cells (ep) was determined with further calculation of the mean number of epithelial cells in the field of view (ep= ep/10). Correlation between the number of abnormal epithelial cells (cp) and the total number of epithelial cells (ep) was analyzed. The resulted "destruction index" (DI) was the "pool" of all cytopathological changes in epithelial cells DI = cp/ep. Immediately after ESWL, DI markedly increased with significant difference (<0.05) in numeric values. Two hours after the procedure, the DI reduced compared to the previous value. And only at day 4 DI was close to the norm, although remaining somewhat elevated.

CONCLUSION

Extracorporeal shock waves lithotripsy produces the acute urothelial damage resulting in cytopathological changes of varying severity. The above-mentioned technique provides objective and highly significant clinical and diagnostic information on the state of the urothelium after the exposure to shock waves.

[Molecular mechanisms of individual platelet reactivity in hematuria secondary to lithotripsy]

AIM

To investigate the mechanisms of individual platelet reactivity to ADP and adrenaline associated with the variability of hematuria after lithotripsy in patients with chronic obstructive pyelonephritis (COPN).

MATERIALS AND METHODS

The study included 41 COPN patients admitted to the Department of Urology for lithotripsy (LT). The contact ultrasonic LT was performed using the Karl Storz Calcuson Ultrasonic Lithotripsy System. Postoperative hematuria was assessed by microscopic red blood cell count. Platelets were separated from the citrated peripheral blood by centrifugation. Platelet aggregation was measured by Chrono-log aggregometer using agonists (ADP, adrenaline) at a concentration of EC50 and EU10.

RESULTS

There were three types of platelet functional response to ADP and adrenaline after LT (increased, unchanged and decreased aggregation), but the predominant type of individual response was increased platelet aggregation. Testing 24 hours after LT revealed 7 platelet phenotypes differing in functional activity of 2-adrenoceptor agonist and purine receptors (R2Y1 and R2Y12). Normal purine receptor activity was associated with the ability of platelets to respond to adrenaline by increasing the functional activity aimed at limiting hematuria. Reduced platelet response to ADP after LT reaching the level of hyporesponsiveness may be viewed as a predictor of severe hematuria after surgery.

CONCLUSION

Individual platelet reactivity, manifested by the interaction of ADP and adrenaline agonist, determines the effectiveness of the increase in pro-aggregation capacity of platelets in developing postoperative hematuria.

Crystalluria

Crystalluria is a marker of urine supersaturation with substances deriving from metabolic disorders, inherited diseases or drugs. The investigation of crystalluria must be done according to a protocol which includes the delivery to the laboratory of a proper urine sample, the use of a microscope equipped with polarized light, the accurate knowledge of urine pH, and a comprehensive examination of the crystals, which is based on their identification, quantification and size measurement. For unusual crystals, infrared spectroscopy may also be needed. The main urinary crystalline categories include: calcium oxalates, calcium phosphates, uric acids and urates, struvite, aminoacids (cystine), purines (2,8-dihydroxyadenine and xanthine) and drugs (e.g. sulfamethoxazole, amoxycillin, ceftriaxone, atazanavir). The investigation of crystalluria is a cheap and valuable tool for the detection and the monitoring of inherited and acquired diseases associated with urinary stone formation or renal function impairment - either acute or chronic - due to intrarenal crystal precipitation.

[Effects of a supplementation on sodium chloride or ammonium chloride on urolithic potential in the rabbit]

AIM

Reduction of urolithic potential by means of increased water intake and urine dilution through supplementation of sodium chloride (NaCl) or decrease of urine pH by supplementation of ammonium chloride (NH4Cl) in rabbits.

MATERIALS AND METHODS

Sixteen female, 6-month-old dwarf rabbits received the following three feeding regimens in a random order: complete feed without supplements = control; complete feed + 10 g NaCl/kg feed = NaCl; complete feed + 2.5 g NH4Cl/kg feed = NH4Cl. The diets were fed ad libitum over a period of 27 days without roughage. Water was provided ad libitum by a drinker. A 14-day wash-out-period (hay feeding) was performed between the different diets. Blood, faeces, and urine were collected at the beginning of each feeding period, after 21-day adaptation to the respective diet, and after the 3-day collection period. The following parameters were analysed: water and food intake as well as acid-base balance and mineral content in blood, urine, and faeces.

RESULTS

NaCl supplementation numerically increased the daily water intake from 40.5 ± 14.4 ml/kg body weight (BW) (control) up to 49.5 ± 14.3 ml/kg BW and significantly increased the daily urine volume from 16.9 ± 7.8 ml/kg BW (control group) to 21.1 ± 7.4 ml/kg BW. The specific gravity of urine samples from NaCl supplementation decreased from 1.060 ± 0.008 to 1.044 ± 0.008. NH4Cl supplementation did not induce significant changes in urine pH, blood acid-base parameters, or calcium retention. Relative supersaturations (RSS) for calcium oxalate and calcium phosphate showed no significant changes after treatment. RSS for struvite increased from 360 ± 735 (after hay feeding) to 3312 ± 6188 on control feeding, 2910 ± 4913 with NaCl supplementation, and 3022 ± 6635 with NH4Cl supplementation (p < 0.05).

CONCLUSIONS

NaCl supplementation significantly increased the urine volume and decreased its specific gravity. Therefore, NaCl supplementation might be an additional dietary treatment to increase the elimination of urine crystals in rabbits. NH4Cl supplementation did not induce acidification of the urine.

Could spot urine analysis of calcium and uric acid help predict density of urinary stone in computerized tomography? A preliminary study

BACKGROUD

This research studies if Hounsfield density of urinary stone can be predicted without computerized tomography (CT) caused by because increased radiation exposure in follow-up of patients.

METHODS

The records of patients with renal or ureteral stone were analyzed retrospectively for the time period between November 2013 and April 2014. The inclusion criteria defined were: no multiple stones; stone size ≥3 mm; presence of renal and ureteral stones; absence of staghorn stone. All CT images were assessed in abdominal windows by a single radiologist. Hounsfield Unit (HU) value of CT was used to interpret the density of the stone. The density of the stone was measured in the longest axis of the stone center (core) and the edges (periphery) of each stone. Biochemical analysis of spot urine calcium (Ca) and uric acid (UA) was done at the time of diagnosis. Correlation and linear regression analysis was performed.

RESULTS

Forty patients were included the study and median age of patients is 22 (IQR 21-28). Since the unit was a military hospital, most patients admitted to hospital were young male conscripts with low median age. It has been found that spot urine uric acid and uric acid/Ca ratio is associated with stone density as HU (P=0.004, P<0.001). Although predictive value appeared low, linear regression model statistically predicted stone density as HU (P<0.001 R2=0.32). Stone size has proved to be positively correlated with stone density (P<0.001).

CONCLUSIONS

Despite the predictive value of urine analysis model is low, it may be considered to predict HU attenuation of stone. Spot urine analysis of calcium and uric acid may be helpful for both diagnosis and follow-up. We believe that controlled studies with larger patient populations will provide further insights into this issue.

Provider variation in the quality of metabolic stone management

PURPOSE

Urinary stone disease is a chronic condition for which secondary prevention (dietary and medical therapy guided by 24-hour urine collection results) has an important role. Assessing the response to these interventions with followup testing is recommended and yet to our knowledge provider compliance with these guidelines is unknown.

MATERIALS AND METHODS

Using Litholink® files from 1995 to 2013 we identified adults with urinary stone disease who underwent metabolic evaluation and the providers who ordered the evaluation. By focusing on patients with an abnormality on the initial collection we determined the proportion who underwent a followup test within 6 months of the initial test. Multilevel modeling was done to quantify variation in followup testing among providers after accounting for various patient and provider factors.

RESULTS

A total of 208,125 patients had an abnormality on the initial collection, of whom only 33,413 (16.1%) performed a repeat collection within 6 months. While most variation in followup testing was attributable to the patient, the provider contribution was nontrivial (18.0%). The specialty of the ordering provider was important. Patients who saw a urologist had 24% lower odds of repeat testing compared to those who saw a primary care physician (OR 0.76, 95% CI 0.67-0.86, p <0.001).

CONCLUSIONS

Followup testing is uncommon in patients with an abnormal initial 24-hour urine collection. Given the observed provider variation, efforts to educate providers on the value of followup testing are likely to have salutary effects on patients with metabolic stone disease.

Nanouric acid or nanocalcium phosphate as central nidus to induce calcium oxalate stone formation: a high-resolution transmission electron microscopy study on urinary nanocrystallites

PURPOSE

This study aimed to accurately analyze the relationship between calcium oxalate (CaOx) stone formation and the components of urinary nanocrystallites.

METHOD

High-resolution transmission electron microscopy (HRTEM), selected area electron diffraction, fast Fourier transformation of HRTEM, and energy dispersive X-ray spectroscopy were performed to analyze the components of these nanocrystallites.

RESULTS

The main components of CaOx stones are calcium oxalate monohydrate and a small amount of dehydrate, while those of urinary nanocrystallites are calcium oxalate monohydrate, uric acid, and calcium phosphate. The mechanism of formation of CaOx stones was discussed based on the components of urinary nanocrystallites.

CONCLUSION

The formation of CaOx stones is closely related both to the properties of urinary nanocrystallites and to the urinary components. The combination of HRTEM, fast Fourier transformation, selected area electron diffraction, and energy dispersive X-ray spectroscopy could be accurately performed to analyze the components of single urinary nanocrystallites. This result provides evidence for nanouric acid and/or nanocalcium phosphate crystallites as the central nidus to induce CaOx stone formation.

[Hormonal and metabolic disorders as systemic factor for the formation of urinary calculi]

In patients suffering from urolithiasis, metabolic diagnostics often reveals abnormalities contributing to the formation of stones: hypocitraturia, hyper- and hypocalcemia, hypercalciuria, hypomagnesemia/hypomagnesuria, hyperoxalaturia, etc. Before surgery, complex biochemical examination of blood and 24-hourcollection urine in 82 patients with urolithiasis was performed. The analysis of the main laboratory parameters of carbohydrate, lipid, calcium and phosphorus and purine metabolism found the prevalence of violations of calcium and phosphorus metabolism in these patients. Dyslipidemia was diagnosed in 31 (37.8%) patients. There was a significant positive correlation between serum total cholesterol and serum total calcium (rs = 0.3315, P = 0.0103). Low serum calcium levels were associated with hyperoxalaturia (rs = -0.4270, P = 0.0295). There was a significant effect of natriuria on urinary excretion of oxalate (rs = 0.6107, P = 0.0001), Mg (rs = 0.4156, P = 0.0096) and K (rs = 0.5234, P = 0.00005). The study shows the role of magnesium in the prevention of recurrence and manifestation of urolithiasis. The combination of two or more types of hormonal and metabolic disorders increases the incidence of recurrent stones. Timely correction of hormonal-metabolic status allows to reduce the risk of stone formation, and hospitalization attributable to the complications associated.

Sulfate but not thiosulfate reduces calculated and measured urinary ionized calcium and supersaturation: implications for the treatment of calcium renal stones

BACKGROUND

Urinary sulfate (SO4(2-)) and thiosulfate (S2O3(2-)) can potentially bind with calcium and decrease kidney stone risk. We modeled the effects of these species on the concentration of ionized calcium (iCa) and on supersaturation (SS) of calcium oxalate (CaOx) and calcium phosphate (CaP), and measured their in vitro effects on iCa and the upper limit of stability (ULM) of these salts.

METHODS

Urine data from 4 different types of stone patients were obtained from the Mayo Nephrology Clinic (Model 1). A second data set was obtained from healthy controls and hypercalciuric stone formers in the literature who had been treated with sodium thiosulfate (STS) (Model 2). The Joint Expert Speciation System (JESS) was used to calculate iCa and SS. In Model 1, these parameters were calculated as a function of sulfate and thiosulfate concentrations. In Model 2, data from pre- and post STS urines were analyzed. ULM and iCa were determined in human urine as a function of sulfate and thiosulfate concentrations.

RESULTS

Calculated iCa and SS values for all calcium salts decreased with increasing sulfate concentration. Thiosulfate had no effect on these parameters. In Model 2, calculated iCa and CaOx SS increased after STS treatment, but CaP SS decreased, perhaps due to a decrease in pH after STS treatment. In confirmatory in vitro experiments supplemental sulfate, but not thiosulfate, significantly increased the calcium needed to achieve the ULM of CaP and tended to increase the oxalate needed to reach the ULM of CaOx. Sulfate also significantly decreased iCa in human urine, while thiosulfate had no effect.

CONCLUSION

Increasing urinary sulfate could theoretically reduce CaOx and CaP stone risk. Although STS may reduce CaP stone risk by decreasing urinary pH, it might also paradoxically increase iCa and CaOx SS. As such, STS may not be a viable treatment option for stone disease.

Predisposing factors for infantile urinary calculus in south-west of Iran

INTRODUCTION

Urinary calculi in infants are relatively infrequent, but their incidence has increased in the recent decades. The aim of this study was to investigate the clinical presentation, metabolic risk factors, and urinary tract abnormalities in infants suffering from kidney calculus.

MATERIALS AND METHODS

A total of 152 infants were admitted between 2009 and 2012 with ultrasonography-proven urolithiasis. A Foley catheter was fixed and 24-hour urine samples were analyzed for calcium, citrate, oxalate, uric acid, and magnesium. For detecting cystinuria, qualitative measurement of urinary cystine was done by nitroprusside test. Urinary tract structural abnormalities were also evaluated.

RESULTS

The mean age at the diagnosis of kidney calculus was 5.46 months (range, 15 days to 12 months). The most common clinical findings were restlessness and urinary tract infection. A family history of calculi was found in 67.1% of the patients and 68.4% were born to consanguineous marriages. Metabolic abnormalities and urinary tract abnormalities were found in 96.1% and 15.1% of children, respectively. Urinary tract abnormalities were more common in girls. The most common metabolic risk factors were hypercalciuria (79.6%) and hypocitraturia (40.9%). Hyperoxaluria and hypomagnesuria were found in about 28% of patients, both of which were associated with bilateral urolithiasis.

CONCLUSIONS

These findings show that urinary metabolic abnormalities are very common in infants with urolithiasis. Appropriate evaluation of urinary metabolic parameters can lead us to proper diagnosis and treatment.

Determinants of brushite stone formation: a case-control study

Purpose

The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear.

Methods

Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed.

Results

Pure brushite stones were present in 46% of patients, while calcium oxalate was the major secondary stone component. Urinary pH and oxalate excretion were significantly higher, whereas urinary citrate was lower in patients as compared to healthy controls. Despite lower dietary intake, urinary calcium excretion was significantly higher in brushite stone patients. Binary logistic regression analysis revealed pH>6.50 (OR 7.296; p = 0.035), calcium>6.40 mmol/24 h (OR 25.213; p = 0.001) and citrate excretion <2.600 mmol/24 h (OR 15.352; p = 0.005) as urinary risk factors for brushite stone formation. A total of 56% of patients exhibited distal renal tubular acidosis (dRTA). Urinary pH, calcium and citrate excretion did not significantly differ between patients with or without dRTA.

Conclusions

Hypercalciuria, a diminished citrate excretion and an elevated pH turned out to be the major urinary determinants of brushite stone formation. Interestingly, urinary phosphate was not associated with urolithiasis. The increased urinary oxalate excretion, possibly due to decreased calcium intake, promotes the risk of mixed stone formation with calcium oxalate. Neither dietary factors nor dRTA can account as cause for hypercalciuria, higher urinary pH and diminished citrate excretion. Further research is needed to define the role of dRTA in brushite stone formation and to evaluate the hypothesis of an acquired acidification defect.

Association of elevated urinary cadmium with urinary stone, hypercalciuria and renal tubular dysfunction in the population of cadmium-contaminated area

Excessive urinary calcium is the major risk of renal tubular dysfunction and urinary stone formation. We examined the association of elevated urinary cadmium with urinary stones and chronic kidney disease (CKD) in 1,085 study residents of 13 cadmium-contaminated villages. Elevated urinary cadmium was significantly correlated with urinary stone and CKD. Elevated urinary cadmium appeared to increase risk of urinary stone and CKD; ORs and 95 % CIs were 2.73 (1.16, 6.42) and 3.73 (2.50, 5.57) after adjusting for other co-variables. This study revealed that elevated urinary stone and CKD induced by cadmium might increase the risk of urinary stone and CKD.

Comparison of 24-hour urinary citrate excretion in stone formers and healthy volunteers

Low urinary citrate excretion is a risk factor in stone formers (SF). This study aimed to measure the urinary citrate excretion in SF and healthy volunteers at our center from 12 June 2008 to 20 August 2009. There were 28 SF patients (18 males and ten females) and 27 (18 males and nine females) age-matched healthy adult volunteers who participated in this study. Both groups had a similar living environment, extrinsic factors, diet and genetic descent. After collecting 24-h urine, citrate was measured using an enzymatic kit. Routine urinalysis and 24-h creatinine and uric acid were also performed. There was a significant difference in urinary citrate excretion level among SF (mean 310, SD 260 mg/L) and normal volunteer subjects (mean 800, SD 300 mg/L). By applying the previously defined normal values (320 mg/24 h) of urinary citrate in the local population, 43% of the SF in our study group was hypocitric, and none among the controls. We conclude that prevalence of hypocitraturia in stone formers was higher than that in healthy volunteers in our population.

Extensive characterizations of bacteria isolated from catheterized urine and stone matrices in patients with nephrolithiasis

BACKGROUND

Urinary tract infections are generally known to be associated with nephrolithiasis, particularly struvite stone, in which the most common microbe found is urea-splitting bacterium, i.e. Proteus mirabilis. However, our observation indicated that it might not be the case of stone formers in Thailand. We therefore extensively characterized microorganisms associated with all types of kidney stones.

METHODS

A total of 100 kidney stone formers (59 males and 41 females) admitted for elective percutaneous nephrolithotomy were recruited and microorganisms isolated from catheterized urine and cortex and nidus of their stones were analyzed.

RESULTS

From 100 stone formers recruited, 36 cases had a total of 45 bacterial isolates cultivated from their catheterized urine and/or stone matrices. Among these 36 cases, chemical analysis by Fourier-transformed infrared spectroscopy revealed that 8 had the previously classified 'infection-induced stones', whereas the other 28 cases had the previously classified 'metabolic stones'. Calcium oxalate (in either pure or mixed form) was the most common and found in 64 and 75% of the stone formers with and without bacterial isolates, respectively. Escherichia coli was the most common bacterium (approximately one-third of all bacterial isolates) found in urine and stone matrices (both nidus and periphery). Linear regression analysis showed significant correlation (r = 0.860, P < 0.001) between bacterial types in urine and stone matrices. Multidrug resistance was frequently found in these isolated bacteria. Moreover, urea test revealed that only 31% were urea-splitting bacteria, whereas the majority (69%) had negative urea test.

CONCLUSIONS

Our data indicate that microorganisms are associated with almost all chemical types of kidney stones and urea-splitting bacteria are not the major causative microorganisms found in urine and stone matrices of the stone formers in Thailand. These data may lead to rethinking and a new roadmap for future research regarding the role of microorganisms in kidney stone formation.

Metabolic assessment of elderly men with urolithiasis

OBJECTIVE

To assess the presence of metabolic disorders in elderly men with urolithiasis.

METHODS

We performed a case-control study. The inclusion criteria were as follows: (1) men older than 60 years of age and either (2) antecedent renal colic or an incidental diagnosis of urinary lithiasis after age 60 (case arm) or (3) no antecedent renal colic or incidental diagnosis of urolithiasis (control arm). Each individual underwent an interview, and those who were selected underwent all clinical protocol examinations: serum levels of total and ionized calcium, uric acid, phosphorus, glucose, urea, creatinine and parathyroid hormone, urine culture, and analysis of 24-hour urine samples (levels of calcium, citrate, creatinine, uric acid and sodium, pH and urine volume). Each case arm patient underwent two complete metabolic urinary investigations, whereas each control arm individual underwent one examination. ClinicalTrials.gov: NCT01246531.

RESULTS

A total of 51 subjects completed the clinical investigation: 25 in the case arm and 26 in the control arm. In total, 56% of the case arm patients had hypocitraturia (vs. 15.4% in the control arm; p = 0.002). Hypernatriuria was detected in 64% of the case arm patients and in 30.8% of the controls (p = 0.017).

CONCLUSION

Hypocitraturia and hypernatriuria are the main metabolic disorders in elderly men with urolithiasis.

An association between urinary cadmium and urinary stone disease in persons living in cadmium-contaminated villages in northwestern Thailand: a population study

Excessive urinary calcium excretion is the major risk of urinary stone formation. Very few population studies have been performed to determine the relationship between environmental cadmium exposure and urinary stone disease. This population-based study examined an association between urinary cadmium excretion, a good biomarker of long-term cadmium exposure, and prevalence of urinary stones in persons aged 15 years and older, who lived in the 12 cadmium-contaminated villages in the Mae Sot District, Tak Province, northwestern Thailand. A total of 6748 persons were interviewed and screened for urinary cadmium and urinary stone disease in 2009. To test a correlation between urinary excretion of cadmium and calcium, we measured urinary calcium content in 1492 persons, who lived in 3 villages randomly selected from the 12 contaminated villages. The rate of urinary stones significantly increased from 4.3% among persons in the lowest quartile of urinary cadmium to 11.3% in the highest quartile. An increase in stone prevalence with increasing urinary cadmium levels was similarly observed in both genders. Multiple logistic regression analysis revealed a positive association between urinary cadmium levels and stone prevalence, after adjusting for other co-variables. The urinary calcium excretion significantly increased with increasing urinary cadmium levels in both genders, after adjusting for other co-variables. Elevated calciuria induced by cadmium might increase the risk of urinary stone formation in this environmentally exposed population.

The most important metabolic risk factors in recurrent urinary stone formers

PURPOSE

To evaluate different urinary factors contributing to idiopathic calcium stone disease for determining appropriate medical treatments.

MATERIALS AND METHODS

Two 24-hour urine samples were collected from 106 male recurrent idiopathic calcium stone formers and another 109 randomly selected men as the control group matching for age.

RESULTS

Cases had significantly higher mean urine oxalate, calcium, uric acid, and chloride in comparison with the healthy controls (P < .001). After necessary adjustment, only mean urine levels of oxalate and uric acid were higher in stone formers than those in controls. The mean value of supersaturation for calcium oxalate was significantly higher in patients than the controls (P = .001); whereas supersaturation for calcium phosphate and uric acid did not reach statistical significance (P = .675 and P = .675, respectively). Hyperoxaluria and hypercalciuria were among the most frequent abnormalities. After categorizing urine parameter values into four quartiles, the risk of stone formation was found to increase as the urine calcium, oxalate, uric acid, chloride, and citrate rise. In contrast, the risk of stone formation decreased with the increase of urine potassium.

CONCLUSION

Oxalate seems to play the most important role as urinary stone risk factor in our population followed by calcium and uric acid. In addition to the risk factors, it seems that supersaturation as the sum of all risk factors probably has a high predictive value.

[Composition analyses of urinary microcrystalline in urine of magnesium ammonium phosphate stones formers and its relationship with the stones formation]

By means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-particle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the composition, morphology, particle size and zeta potential of urinary microcrystalline in urine of magnesium ammonium phosphate stone formers were investigated. The components of stones were also analyzed. The results showed that there was a close relationship among stone components, urinary microcrystalline composition and urine pH. A high pH value of 6.5 or more usually appeared in the urine of magnesium ammonium phosphate stone formers. The main component of urine microcrystalline was magnesium ammonium phosphate crystals with different crystal water such as monohydrate or hexahydrate. Magnesium ammonium phosphate crystals are mainly petal-shaped, crosswise shape. These microcrystalline have an uneven particle size distribution, a wider distribution range, and apparent aggregation. There is no significant difference in the zeta potential between the magnesium ammonium phosphate stone formers (mean (-9.83 +/- 0.66) mV) and healthy control subjects (mean (-10.74 +/- 0.25) mV). This study can help predict the occurrence of urolithiasis, and provide inspiration to the prediction of the type of urinary stones.

Clinical significance of uric acid dihydrate in urinary stones

Uric acid crystallizes as an anhydrous compound (UAA), a dihydrate (UAD) or a mixture of both. A monohydrate form is very rare. About 20% of uric acid stones contain a significant amount (≥20%) UAD. It is believed that UAD crystallizes under highly acidic conditions (urine pH ≤ 5.0). Up to now, metabolic data on patients with UAD stones have not been reported in the literature. One hundred and fifty patients with pure uric acid calculi were studied. Stone analysis was performed using X-ray diffraction. According to the stone analysis, they were divided in two groups: 1. UAD (≥20% UAD), 2. UAA (<20% UAD). In all patients the following parameters were examined: age, sex, number of recurrences, body mass index (BMI); blood: creatinine, uric acid, calcium, sodium, and potassium; urine: pH-profiles, volume, calcium, uric acid, citrate, ammonia, and urea. Group 1 (≥20% UAD) consisted of 33 patients and group 2 (<20% UAD) of 117 patients. Between these groups, there was a significant difference concerning the number of recurrences, the urine volume, and the urinary excretion of calcium. Patients with ≥20% dihydrate had a mean BMI of 31.6 ± 7.5, a mean number of recurrences of 0.24 ± 0.44, an urine volume of 2.6 ± 0.8 l/24 h, and a calcium excretion of 4.5 ± 2.2 mmol/24 h, whereas those with <20% dihydrate had BMI of 29.9 ± 5.0, 1.10 ± 1.42 recurrences, urine volume of 2.3 ± 1.2 l/24 h, and calcium excretion of 3.2 ± 2.4 mmol/24 h. All the other parameters tested were not significantly different. For the first time, our study shows metabolic data in uric acid patients with a significant amount of UAD. The comparison between this group and those patients with <20% UAD revealed that the first group is less prone to develop recurrences. This is a relevant difference concerning the necessity of metaphylactic measures. We could not confirm in patients with dihydrate if the urinary pH is more acid than in those with insignificant amounts of dihydrate. The higher 24-h urine volume, the higher excretion of calcium, and the higher BMI in the UAD group may be of pathophysiological relevance and requires further attention.

Microelements in stones, urine, and hair of stone formers: a new key to the puzzle of lithogenesis?

The role of trace elements in lithogenesis is still unclear. The aim of this study was to evaluate the levels of elements in urinary stones and in the urine and hair of stone formers to identify these elements that have synergic correlations in studied materials and may contribute to lithogenesis. A total of 219 consecutive patients with idiopathic upper urinary tract stones were prospectively enrolled in the study. Urine and hair samples were collected from all patients. The content of the stone was evaluated using atomic absorption spectrometry, spectrophotometry, and colorimetric methods. The analysis of 29 elements in stones and hair and 21 elements in urine was performed using inductively coupled plasma-atomic emission spectrometry. The strength of correlation was described with the value of Spearman's rank correlation coefficient. The positive correlation between concentration of sodium, potassium, magnesium, barium, vanadium, zinc, silicon, phosphorus, and iodine in phosphate stones was observed. Only a few incidental correlations between the composition of stones and the distribution of elements in urine and in hair were found. There were 109 positive two-element correlations between two materials. The most common were observed for vanadium, aluminum, lead, cobalt, and molybdenum. Two-element positive correlations for all samples were established only for three elements: vanadium, lead, and aluminum. Results indicate that analysis of particular elements in hair and urine cannot predict the composition of urinary stones. This study showed, for the first time, correlations between the levels of vanadium, lead, and aluminum in the stones, urine, and hair of stone formers.