Uric Stones Research Articles

Environmental factors of urinary stones mineralogy, Khouzestan Province, Iran

Urinary stone diseases in the Khouzestan province (southwest Iran) are growing in number and it required extensive studies on various factors of the urinary stones formation in this province. In this research, in addition to distribution of urinary stones in different areas of province, the role of bioenvironmental (race), climate (temperature) and geology (water hardness) factors in urinary stones diversity has been studied. Mineralogical studied using X-ray diffraction showed that uricite and whewellite are the most frequency mineral phases. Struvite, Cystine, hydroxyapatite, weddellite, and Niahite can be observed as urinary stones, too. These data show that the urinary stone in the Khouzestan province can divide into 7 groups: calcium oxalate, phosphate, calcium oxalate/ phosphate, Urate, Urate/calcium, Urate/calcium oxalate/phosphate, Cystine/calcium oxalate. Also the results which attained from temperature effect investigation on the mineralogy of urinary stones, confirms that from Mediterranean sub-humid climates (northeastern area) to warm and dry climates (south and southwest area), calcium oxalate stones and urate stones concentration decreases and increases respectively. Comparison of data related to the drinking water hardness and mineralogy of urinary stones in different areas of Khouzestan province show that the combination of drinking water (especially water hardness) affects mineralogy of urinary stones in some areas (such az Ramhormoz and Hendijan). Finally, the data suggest that frequency of calcium oxalate in women is more than that of men. Moreover, there is direct relationship between the age (>45years) and the increase in frequency of Urate minerals.

Pathophysiological and Physicochemical Basis of Ammonium Urate Stone Formation in Dolphins

Nephrolithiasis is increasingly reported in bottle-nosed dolphins. All cases to date have been ammonium urate nephrolithiasis. A case-control study was performed in dolphins with and without evidence of nephrolithiasis to identify biomarkers and risk factors associated with stone formation in a managed population. Dolphins were sampled in fasting and postprandial states to study the effect of dietary factors on serum and urinary biochemistry. Urine was continuously collected for 6 hours via catheter and divided into 3, 2-hour collections with a bolus fish meal given after completing the first collection. Blood was sampled at the beginning of the fasting period and the end of the postprandial period. There were no significant differences in serum and urine chemistry or acid-base profiles between dolphins with vs without stones at baseline or postprandially. This suggests that cases and controls represent a continuum of stone risk. On analysis combining cases and controls in a single cohort we noted significant postprandial increases in urinary uric acid, sulfate and net acid excretion accompanied by increased urinary ammonium excretion and a commensurate increase in urine pH. The supersaturation index of ammonium urate increased more than twofold postprandially. These findings suggest that dolphins are susceptible to ammonium urate nephrolithiasis at least in part because a high dietary load of acid and purines results in a transient but marked increase in the urinary supersaturation of the sparingly soluble ammonium urate salt.

Who makes uric acid stones and why—observations from a renal stones clinic

AimsExcessively acidic urine is the dominant factor in uric acid stone formation. Recent evidence implicating insulin resistance has revived interest in its causation. We reviewed data on uric acid stone...

Veterans Affairs databases are accurate for gout-related health care utilization: a validation study

IntroductionThe aim of this study was to assess the accuracy of Veterans Affairs (VA) databases for gout-related health care utilization.MethodsThis retrospective study utilized VA administrative and clinical databases. A random sample of gout patients with visits (outpatient, inpatient or emergent/urgent care) with or without the diagnosis of gout (International Classification of Diseases, ninth revision, common modification ICD-9-CM code of 274.x or 274.xx) at the Birmingham VA hospital was selected. A blinded abstractor performed a review of VA electronic health records for the documentation of gout or gout-related terms (gouty arthritis, tophaceous gout, tophus/tophi, acute gout, chronic gout, podagra, urate stones, urate or uric acid crystals and so on) in the chief complaint, history of present illness or assessment and plan for the visit; this constituted the gold standard for gout-related utilization. The accuracy of database-derived gout-related claims was assessed by calculating sensitivity, specificity, and positive and negative predictive values (PPV and NPV).ResultsOf 108 potential visits, 85 outpatient, inpatient or urgent care/emergency room visits to a health care provider (85 patients: 84 men and 1 woman with a mean age of 63 years) and retrievable data from medical records constituted the analyzed dataset. Administrative claims for gout-related utilization with ICD-9 code for gout were accurate with a PPV of 86%, specificity of 95%, sensitivity of 86% and NPV of 95%.ConclusionsVA databases are accurate for gout-related visits. These findings support their use for studies of health services and outcome studies. It remains to be seen if these findings are generalizable to other settings and databases.

Effect of BMI and urinary pH on urolithiasis and its composition

Urolithiasis is a common urological disease predominantly affecting males. The lifetime risk of urolithiasis varies from 1% to 5% in Asia, 5% to 9% in Europe, 10% to 15% in the USA and 20% to 25% in the middle-east; lowest prevalence is reported from Greenland and Japan. Such differences have been explained on the basis of race, diet and climate factors. Furthermore, changing socio-economic conditions have generated changes in the prevalence, incidence and distribution for age, sex and type of lithiasis in terms of both the site and the chemical as well as the physical composition of the calculi. The aim of our study was to determine the association between body mass index (BMI) and urine pH in patients with urolithiasis and the influence of body size, as reflected by the BMI, on the composition. The study was conducted in the Department of Biochemistry, Maharishi Markandeshwar Institute of Medical Sciences and Research, on urolithiatic patients. The data included patient's age, sex, BMI, urine pH, serum calcium, serum uric acid, serum creatinine and stone composition. Data from 100 patients, 70 men (70%) and 30 women (30%), were analyzed, with 28 patients having normal weight, 38 patients being overweight and 34 patients being obese. The mean age of the patients was 36.58 ± 9.91 years in group I, 40.47 ± 14.48 years in group II and 37.85 ± 12.46 years in group III (P > 0.05). The stone composition was calcium oxalate (CaOx) in 66 patients, calcium phosphate (CaP) in 60 patients, uric acid (UA) in 38 patients, combined calcium oxalate and calcium phosphate in 28 patients and three stones in 10 patients. The urinary pH levels (mean ± SD) were 7.78 ± 1.49 in group I, 7.15 ± 1.11 in group II and 6.29 ± 1.14 in group III patients (P = 0.0001). Urine pH showed a stepwise decrease with increasing BMI (inverse correlation). Urine pH is inversely related to BMI among patients with urolithiasis, as is the occurrence of urate, calcium oxalate and calcium phosphate stones. Similarly, the serum creatinine increased as the BMI and number of stones increased among the study population.

Acidosis with hyperuricemia and renal tubular damage in viral gastroenteritis

Acidosis with hyperuricemia and renal tubular damage in viral gastroenteritis

Enigma of uric acid stones associated with rotavirus-associated gastroenteritis

Sirs,We are grateful to Dr. Fujieda for suggesting anotherpossibility as the cause for uric acid stones associated withrotavirus-associated gastroenteritis [1].The pathogenesis of urate stone formation in children withhuman rotavirus (HRV)-associated gastroenteritis, which wasmainly reported from Japan, remains unknown. As formationof urolithiasis consisting of urate, which is rarely seen inchildren, is generally associated with increased urinaryexcretion of uric acid, previous reports have proposed severalpossibilities of hyperuricuria being the cause.Possible causes of hyperuricuria in this condition include:1. Hyperuricemia due to massive breakdown of intestinalcells due to HRV [2]2. Severe dehydration caused by HRV infection [2]3. Renal hypouricemia associated with mutation of humanurate transporter 1 (URAT1) gene [3]Fujieda et al. [1] suggest another intriguing hypothesis thatHRVmightinfectnotonlysmallintestinalcells,butalsorenaltubularcells,whichleadstoincreasedurinaryconcentrationofuric acid in conjunction with increased excretion of beta-2-microglobulin and N-acetyl-β-glucosaminidaseHowever, none of the possibilities mentioned above hasclearly answered the following questions:1. Why is this condition reported mainly in Japan?2. Do other viruses causing gastroenteritis, such asnorovirus or adenovirus infect renal tubular cells?3. Is an infection of the renal epithelial cells exclusivelycharacteristic of HRV?4. Why do most of the children with HRV-associatedgastroenteritis not have the complication of urateurolithiasis?Until these questions have been clarified, the pathogenesisof urolithiasis in children with HRV-associated gastroenteritiswill remain enigmatic.References

Miscellaneous Stone Types

Drug-induced calculi and other rare stone types, such as ammonium acid urate or protein matrix stones, represent only about 2% of all renal calculi. However, the chance to easily reverse stone formation risk by discontinuing the offending drug makes identification of these entities important for clinicians. Additionally, study of these rare stone types contributes to understanding the biochemistry of stone formation. Drug-induced calculi may be classified into two groups based on the mechanism of stone formation. The first group includes drugs that provoke calculi composed of principally the drug and its metabolites. These medications tend to be poorly soluble, highly excreted in urine, and required at high dosages for long durations of therapy. Historically, sulfonamides, triamterene, and the HIV protease inhibitor indinavir were leading causes of drug-induced calculi. Uses of novel agents within these drug classes or alternative therapies have reduced the incidence attributed to these drugs, although risk from newer, commonly used medications–notably ciprofloxacin, aminopenicillins, ceftriaxone, ephedrine, and guaifenesin– are increasingly being recognized. Microscopic analysis for crystalluria or infrared spectroscopy of collected stones aid in recognition of calculi composed primarily of a drug and its metabolites. Understanding of drug metabolism and pharmacokinetics, particularly related to effects of urine pH on drug solubility and excretion, provides a rational basis for both prevention and treatment recommendations. When possible, clinicians should avoid or exercise great caution when prescribing these medications to patients with a prior history of stones. The second group of drug-induced calculi includes drugs that cause stones due to their metabolic effects, primarily on calcium or purine metabolism. Because these calculi are identical in physical composition to the more common nephrolithiasis types, careful medication history and high clinical suspicion are required for diagnosis of these drug-induced “metabolic” calculi. Most drugs in this class are readily expected based on their effects on urinary calcium excretion such as calcium/Vitamin D supplements and loop diuretics. Carbonic anhydrase inhibitors, including the antiepileptics topiramate and zonisamide, are also included in this group. Ammonium acid urate stones are endemic in developing countries due to dietary limitations and recurrent diarrheal illness, but rarely occur in developed countries. Identification of these stones should raise clinical suspicion of epidemiologic risk factors including recurrent urinary tract infections with urea-splitting organisms, inflammatory bowel disease, and laxative abuse. Interestingly, these unusual clinical scenarios can recapitulate a common biochemical pathway to stone formation. Protein matrix stones are another unusual stone type associated with specific epidemiologic factors, namely recurrent urinary infections and proteinuric end-stage renal disease. Although distinctly rare, protein matrix stones provide opportunity to investigate basic biochemical mechanisms underlying stone formation.

Infrared spectroscopic analysis of urinary stones (including stones induced by melamine-contaminated milk powder) in 189 Chinese children

AimThe aim of the study was to investigate the composition of the stones in Chinese children with urolithiasis, including peculiar stones induced by melamine-contaminated milk powder. Materials and MethodsBetween 1999 and 2009, 189 urinary stones from children of East China were received at our institution. Among them, 12 stones were received from pediatric stone formers with a history of consuming melamine-contaminated milk powder in 2008; and the remaining stones were defined as “natural” stones. All stones were analyzed by Fourier transform infrared spectroscopy. ResultsAmong 177 “natural” stones, whewellite stone (49.72%) was observed most frequently followed by weddellite stone (15.25%), uric acid anhydrous stone (9.6%), carbapatite stone (9.04%), cystine stone (9.04%), ammonium acid urate stone (4.52%), struvite stone (2.26%), and sodium urate stone (0.56%). Twelve young children who consumed melamine-contaminated milk powder were younger than 3 years, and their stones were composed of a mixture of uric acid dihydrate and ammonium acid urate based on Fourier transform infrared spectroscopy. In addition, the stones were radiolucent and could be dissolved by urine alkalinization. ConclusionsOur study emphasizes the relatively high rate of calcium oxalate stones and cystine stones, and the relatively low rate of struvite stones in Chinese children with urolithiasis. The stones caused by melamine-contaminated milk powder are composed of the mixture of uric acid dihydrate and ammonium acid urate.

Application of LIIR Automatic Analysis System of Infrared Spectroscopy in the determination of urinary stone composition

Objective To determine the value of applying LIIR Automatic Analysis System of Infrared Spectroscopy in analyzing urinary stone composition. Methods 1450 samples of urinary stones were collected from 1032 male and 418 female patients. The age of patients ranged from 6 months to 88 years. The mean ages were 41.7±15.3 and 42.0±15.6 years for male and female pa- tients, respectively. Of 1450 stones, 875 cases were located in kidney （60.34%）, 504 cases in ureter （34.76%） and 71 cases in bladder （4.90%）. All stones were analyzed by LIIR Automatic Analysis System of Infrared Spectroscopy （Tianjin）. Analysis results were reevaluated by the artificial analysis of spectrogram, i{ necessary, with polarization microscope, chemical analysis, and X ray diffraction. Results Calcium oxalate monohydrate stones were found in 714 cases （49. 24%）, carbonate apatite stones in 444 cases （30.62%）, anhydrous uric acid stones in 93 cases （6.41%）, calcium oxalate dihydrate stones in 92 cases （6. 34%）, ammonium magnesium phosphate hexahydrate stones in 28 cases （1. 93%）, cystine stones in 23 cases （1.59%）, ammonium urate stones in 20 cases （1.38%）, uric acid dihydrate stones in 16 cases （1.10%）, brushite stones in 12 cases （0. 83%）, sodium urate monohydrate stones in 2 cases （0. 14%）, calcium carbonate stones in 1 cases （0.07%）, and other stone types in 5 cases （0.34%）. Most urinary stones were composed of 2 or more compositions, and purestones were only observed in 397 cases （27.38%）. Most of the mixed stones contained calcium and non-calcium mixed stone was rarely observed. In addition, 15 stones were found in infants who had consumed melamine-contaminated milk powder. These stones were composed of uric acid dihydrate and ammonium urate. The results of reevaluation by artificial analysis showed the following among pure and mixed stones, false detection occurred in 6 cases （0.41%）, of which the composition was ammonium urate or carbonate apatite determined by automatic system but the true composition was an hydrous uric acid. False negative detection occurred in 9 cases （0.62%）, of which the composition was ammonium magnesium phosphate hexahydrate or carbonate apatite in 7 cases, but in other 2 cases the composition could not be determined by artificial analysis. The false negative detection of compo- nents with relatively low content occurred in 6 cases and 10 cases in stones with 2 components and 3 components, respectively. The undetected composition in these cases was ammonium magnesium phosphate hexahydrate or carbonate apatite. Conclusion Automatic Analysis System of Infrared Spectroscopy has many advantages in accuracy, automation and is quick in analyzing the composition of urinary stones, and is worthy of promotion in clinical use. Key words: Urinary calculi; Spectrophotometry, infrared; Calcium oxalate; Apatites

Infrared spectrophotometry for crystalline composition of staghorn calculi

To provide theoretic rationales for treatment and prevention of staghorn calculi by analyzing stone composition and studying the relationship between stone and urinary tract infections. The clinical data of 51 staghorn calculi patients were analyzed retrospectively. The stone compositions were studied by infrared spectrophotometry. Six types of stone compositions were obtained. There were calcium oxalate monohydrate, calcium oxalate dehydrate, carbonate apatite, magnesium ammonium phosphate hexahydrate, uric acid and L-cystine. The majority of stones were of mixed compositions, pure stones were found in 15 cases (29.4%). Among all stones, calcium oxalate stones were found in 41 cases (80.4%) and uric stones in 10 cases (19.6%). Infectious stones were found in 26 cases (51.0%). Urinary tract infections were found in 40 (78.4%) patients and positive urine/stone culture was detected in 33 (64.7%) patients. With multiple crystalline compositions and etiological factors, the staghorn calculi are closely correlated with urinary tract infections.

In Vivo Determination of Urinary Stone Composition Using Dual Energy Computerized Tomography With Advanced Post-Acquisition Processing

We assessed whether dual energy computerized tomography with advanced post-image processing can accurately differentiate urinary calculi composition in vivo. A total of 25 patients scheduled to undergo ureteroscopic/percutaneous nephrolithotomy were prospectively identified. Dual energy computerized tomography was performed using 64-slice multidetector computerized tomography. Novel post-processing (DECTSlope) used pixel by pixel analyses to generate data sets grayscale encoding ratios of relative differences in attenuation of low (DECT80 kVp) and high energy (DECT140 kVp) series. Surgical extraction and Fourier spectroscopy resulted in 82 calculi. Of these stones 51 showed minor admixtures (uric acid, ammonium urate, struvite, calcium oxalate monohydrate and brushite) and 31 were polycrystalline (mixtures of calcium oxalate monohydrate/dihydrate and calcium phosphate). Analyses identified stone clusters of equal composition and distinct attenuation descriptors on DECT140 kVp, DECT80 kVp and DECTSlope. Iterative cross-validation of the 3 dual energy computerized tomography data sets was used to identify characteristic attenuation limits for each stone type. Attenuatio profiles showed substantial overlap among various stones on DECT140 kVp (uric acid 427.3±168.1 HU, ammonium urate 429.9±99.7 HU, struvite 480.2±123.5 HU, calcium oxalate monohydrate 852.4±301.4 HU, brushite 863.7±180.1 HU and polycrystalline 858.1±210.5 HU) and on DECT80 kVp (uric acid 493.6±182.8 HU, ammonium urate 591.5±157.9 HU, struvite 712.4±173.9 HU, calcium oxalate monohydrate 1,240.5±494.7 HU, brushite 1,532.1±273.1 HU and polycrystalline 1,358.7±316.8 HU). Statistically spectral separation was not sufficient to characterize stones unambiguously based on DECT140 kVp/DECT80 kVp attenuation. Analysis of attenuation showed sufficient spectral separation on DECTSlope (uric acid 14.9±10.9 U, ammonium urate 56.1±1.8 U, struvite 42.7±1.4 U, calcium oxalate monohydrate 62.8±1.8 U and brushite 113.2±5.3 U). Polycrystalline stones (51.8±3.7 U) overlapped with struvite and ammonium urate stones. This overlap was resolved as all struvite/ammonium urate stones measured 900 HU or less and all polycrystalline stones measured more than 900 HU on DECT80 kVp. Dual energy computerized tomography with novel post-processing allows accurate discrimination among main subtypes of urinary calculi in vivo and, thus, may have implications in determining the optimum clinical treatment of urinary calculi from a noninvasive, preoperative radiological assessment.

Obesity and Chronic Kidney Disease

Obesity is a common contributing factor to the development of chronic kidney disease (CKD). Obesity participates in the genesis of CKD by predisposing to diabetic nephropathy, hypertensive nephrosclerosis, and focal and segmental glomerular sclerosis. It also predisposes to calcium oxalate and urate stones. Additionally, obesity is associated with an increased prevalence and magnitude of proteinuria and a more rapid progression to CKD. There are many mechanisms by which obesity alters renal physiology and metabolism. More effective methods for treating obesity and preventing the development and progression of obesity-associated CKD are clearly needed. Therefore, there is a greater need for a better understanding of the causes of the excessive energy intake that leads to obesity and the mechanisms responsible for the refractoriness of obese individuals to treatment.

Acute renal failure due to obstructive urate stones associated with norovirus gastroenteritis

Acute renal failure due to obstructive urate stones associated with norovirus gastroenteritis

Pathologie pleurale

To evaluate and profile ammonium acid urate (AAU) stone formers utilizing a large contemporary cohort.A retrospective review of all patients with documented AAU urolithiasis on stone analysis was performed from 1995 to 2013. A stone was considered AAU if it contained at least 10% of the total composition on stone analysis.Of 12,421 stones, a total of 111 AAU stones were identified in 89 patients. Seventy-two patients (81%) had mixed composition stones. Of the 89 AAU patients, 10 (11%) had chronic kidney disease, 12 (13%) had recurrent urinary tract infections, 8 (9%) had diabetes mellitus, 25 (28%) had a history of ileostomy or bowel resection, and 11 (12%) had significant diarrhea or inflammatory bowel disease. Additionally, 20 (22%) had prior prostate surgery with bladder neck contracture and 8 (9%) were managed with a chronic indwelling catheter. Surgical intervention was required in 74 patients (83%). At the median follow-up of 4.9 years, 19 patients (21%) had stone recurrence with a median time to recurrence of 22 months (interquartile range: 10.5-42.0).AAU stones are rare. In addition to previously described risk factors for AAU stone formation, patients with prior prostate surgery and bladder neck contracture or a surgically altered bladder may be at increased risk for formation. Furthermore, the long-term follow-up provided by this large AAU cohort demonstrates a significant risk for stone recurrence.

1888 CHANGING STONE COMPOSITION IN RECURRENT STONE FORMERS

You have accessJournal of UrologyStone Disease: SWL, Ureteroscopic or Percutaneous Stone Removal IV1 Apr 20101888 CHANGING STONE COMPOSITION IN RECURRENT STONE FORMERS Kashif Alvi, Mohummad Siddiqui, Ahmad Sharif-Tabrizi, Stephen Dretler, and Dianne Sacco Kashif AlviKashif Alvi More articles by this author , Mohummad SiddiquiMohummad Siddiqui More articles by this author , Ahmad Sharif-TabriziAhmad Sharif-Tabrizi More articles by this author , Stephen DretlerStephen Dretler More articles by this author , and Dianne SaccoDianne Sacco More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1842AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Nephrolithiasis is a recurrent condition in which approximately 50-70% of all stone formers have a risk of subsequent stone formation. Preventative treatment is based on the stone type as well as serum and urinary metabolic factors. The possibility that a recurrent stone former can make more than one stone type over time was evaluated. METHODS A medical record review was performed on 302 patients who had repeat stone analysis between 1988 and 2008. Stone analyses were performed on stones retrieved either after ureteroscopy/laser lithotripsy, percutaneous ultrasonic lithotripsy or from voided specimens. The same stone laboratory analyzed all these stones by x-ray crystallography. The stones were noted to be of following types: Calcium phosphate- Carbonate, Calcium oxalate monohydrate, Calcium oxalate dihydrate, Ammonium Urate, Brushite (Calcium hydrogen phosphate dihydrate), Struvite, Uric Acid, Cystine, Ammonium Urate, and Xanthine stones. RESULTS A total of 302 patients and 736 stone analyses were reviewed. Out of the 302 patients, 173 patients had change in their stone analyses over a certain period of time. A total of 193 stone analyses had changed from one mixed type to a different mixed type, 41 stone analyses changed from a pure stone type to a mixed stone type, 40 analyses changed from a mixed stone type to a pure stone type and 10 stone analyses had changed from one pure stone type to another pure stone type. Among 10 pure stone type changes, 5 stone analyses had a change from uric acid stone into calcium oxalate monohydrate & 2 analysis had changed from uric acid stone to calcium oxalate monohydrate stone. Hence, stone composition changed in 173 (57%) patients in this study upon repeat stone analysis. The most common stone composition change was calcium oxalate monohydrate. CONCLUSIONS Stone composition may change in recurrent stone formers with subsequent stone analysis. It is especillay important when one pure stone type is completely replaced by a totally different stone. These findings suggest that a solitary stone analysis may not be reliable in long term management of recurrent stone formers. Boston, MA© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e734 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kashif Alvi More articles by this author Mohummad Siddiqui More articles by this author Ahmad Sharif-Tabrizi More articles by this author Stephen Dretler More articles by this author Dianne Sacco More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

ロタウィルス腸炎後に両側尿管結石による急性腎不全を呈した２幼児例

We report on 2 infants with acute renal failure caused by bilateral obstructive ureteral stones associated with rotavirus gastroenteritis. A 28-month boy and a 13-month boy with several days history of watery diarrhea and vomiting were referred to our hospital because of anuria. They were diagnosed acute post-renal failure due to obstructive bilateral ureteral stones based on the findings of ultrasound scan and computed tomography. Immediately, percutaneous nephrostomy tubes were inserted for urinary drainage, serum levels of creatinine and uric acid returned to normal within several days. Sandy stones were excreted through the nephrostomy tubes with urine after urinary alkalization, which were proved to be mainly ammonium acid urate. Ammonium acid urate is rare in developed countries, but some cases of bilateral urolithiasis causing acute renal failure in infants with rotavirus gastroenteritis were reported in recent years. It has been known that the cause of acute renal failure is renal azotemia resulting from sustained hypovolemia, but post-renal causes due to ammonium acid urate stones should be taken into consideration.

Management of gout: Primary care approach

AbstractGreat strides have been made in understanding gout as a disease over the centuries. Despite these advances, reports suggest that the management of gout is relatively suboptimal at the primary care level. This article reviews important considerations in the management of gout and provides an evidence-based approach for the management of acute and chronic gouty arthritis at the primary care level. Recurrent monoarticular pain and swelling should raise the suspicion of gout and the demonstration of urate crystals in synovial fluid during a clinical episode confirms the diagnosis. Acute gouty attacks should be managed with appropriate doses of non-steroidal anti-inflammatory drugs (NSAIDs) or colchicines or steroids. Recurrent attacks of gout, presence of tophi and urate stones necessitate urate-lowering drugs. Prophylactic anti-inflammatory agents for up to six months should be added at initiation of urate-lowering therapy to reduce flares of acute attacks. Gout management requires lifelong commitmen...

Effect of Drinking Water on Formation of Renal Calculi

The environmental impact on human health is of increasing concern mainly due to the complex interaction between various hazardous factors both on environment and within human organism. The aim of this paper is to investigate possible correlations between the quality parameters of drinking water and the formation of uroliths. The constituents of some kidney calculi sampled after surgery from 90 patients coming from the Horezu – Valcea area have been analysed, this region being identified as having the most cases of kidney lithiasis and that might be related with hard drinking waters. The study has been made during the period of 2004 – 2008. Physical – chemical methods specific for characterization of the quality of drinking waters have been used in parallel with determination of composition and structural characterization by X-ray diffraction, thermal analysis TG, ATD, FT-IR spectroscopy, optical microscopy. Four groups of uroliths have been identified: multiphase oxalate and urate, phosphate (hydroxiapatite) and carbonate, monohydrated oxalate (whewellite), and urate stones. Such research might be useful, from both chemical and biochemical point of view, for identifying the conditions that cause the inhibition of the processes related to kidney calculi formation.

Attitude to nephrolithiasis in the potential living kidney donor: a survey of the German kidney transplant centers and review of the literature

Living donor kidney transplantation (LD-KTX) is increasing worldwide. With the prevalence of urolithiasis ranging between 4% and 15%, the number of donors with current nephrolithiasis or a history of the disease will increase as well. A questionnaire was sent to all German centers with LD-KTX programs (urologists and general surgeons). Answers were compared for differences between urological and surgical kidney transplant centers. Response rate was 74%. Nephrolithiasis at the time of KTX is an exclusion criterion at 36% of the German centers (58% urological/19% surgical, chi(2) = 4.65, p = 0.03, Fishers exact p = 0.05), 96% of the centers accept kidney donors with a history of nephrolithiasis. The length of the stone-free episode is regarded as relevant by 42% of all centers (58% urological vs. 32% surgical centers, p = ns). Stone composition is a criterion for 54% of centers (66% vs. 44%, p = ns). More than half of the centers accept a history of cystine stones, almost all centers of struvite and urate stones. Donors with current nephrolithiasis were less commonly accepted by urologists than by general surgeons. For almost all centers history of nephrolithiasis does not preclude living kidney donation. Stone composition proved to be of little relevance for decision making.