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Introduction: Crystalluria is an important indicator of renal stone recurrence. Mechanisms underlying urinary stone formation are still not fully understood and raising interests has been giving to intestinal commensal bacteria for their contribute in maintaining urinary solutes equilibrium. The aim of our phase II study was to examine the administration of potassium citrate, magnesium and probiotics in order to reduce crystalluria. Materials and Methods: Since May 2021, we enrolled 23 patients candidates for ureterorenolithotripsy for calcium oxalate kidney stones with crystalluria and a normal metabolic profile. The analysis was validated by the Institution's Ethical Committee (no. approval STS CE Lazio 1/N-823). At discharge, patients were provided with daily food supplementation for 20 days of 1 billion Lactobacillus paracasei LPC09, 1 billion Lactobacillus plantarum LP01, 1 billion Bifidobacterium breve BR03, potassium (520 mg), citrate (1400 mg), and magnesium (80 mg). Crystalluria was re-assessed at 1, 3, 6, and 12-months follow-up by polarized light microscopy. Results: After one month from the oral supplementation, no patient reported crystalluria; at 3 months, among the 20 participants available for re-evaluation, still no patient reported crystalluria. Instead, crystalluria was reported in three patients (15%) at 6 months, and in five patients (25%) at 12 months follow-up. Conclusions: The oral supplementation with Lactobacillus spp. and Bifidobacterium spp. was found able to reduce the prevalence of crystalluria in a cohort of patients with diagnosis of calcium oxalate kidney stones with crystalluria candidate to ureterorenolithotripsy. [ABSTRACT FROM AUTHOR]

Crystalluria, characterized by the formation of calcium oxalate crystals, is a common urinary disorder. While increasing urinary volume is a traditional approach to manage this condition, novel therapeutic strategies are being explored. Lemon juice (LJ), rich in citric acid, is of particular interest due to its calcium ion chelating properties. This study evaluated the in vitro potential of LJ to inhibit calcium oxalate crystal formation. Using specialized electrodes (CPE-GC) and various electrochemical techniques (SWV, CV, LV, EIS), we characterized the interactions between LJ and calcium ions. Our findings, obtained from a simplified model using calcium carbonate, demonstrate the ability of LJ to effectively complex calcium ions, thereby reducing their availability for crystal formation. Although these results are promising, it's important to note that the experimental conditions do not fully replicate the complexity of physiological urine. In vivo studies are therefore necessary to confirm the efficacy of LJ in a clinical setting. In conclusion, lemon juice appears to be a promising approach for preventing calcium oxalate crystal formation. Its mechanism of action, based on calcium ion chelation, offers an alternative to conventional treatments. However, further research is required to evaluate its clinical efficacy and optimize its usage. [ABSTRACT FROM AUTHOR]

This study aimed to assess the ability of rosmarinic acid (RA) to prevent kidney stone formation in an ethylene glycol and ammonium chloride (EG/AC) model. There was an increase in diuresis in the normotensive (NTRs) and hypertensive rats (SHRs) treated with hydrochlorothiazide (HCTZ) and exposed to EG/AC, while RA restored urine volume in NTRs. The EG/AC groups exhibited lower urine pH and electrolyte imbalance; these parameters were not affected by any of the treatments. Both HCTZ+EG/AC and RA+EG/AC reduced calcium oxalate crystal formation in NTR and SHR urine. Kidney tissue analysis revealed alterations in oxidative stress and inflammation parameters in all EG/AC-receiving groups, with RA enhancing antioxidant defenses in SHRs. Additionally, crystals were found in the kidney histology of all EG/AC-exposed groups, with reduced Bowman's capsule areas in NTRs and SHRs. The NTR VEH+EG/AC group showed intense renal damage, while the others maintained their structures, where treatments with HCTZ and RA were fundamental for kidney protection in the NTRs. Docking analysis showed that RA exhibited good binding affinity with matrix metalloproteinase-9, phosphoethanolamine cytidylyltransferase, and human glycolate oxidase enzymes. The data disclosed herein underscore the importance of further research to understand the underlying mechanisms better and validate the potential of RA for clinical use. [ABSTRACT FROM AUTHOR]

Abstract Cotrimoxazole (Trimethoprim/Sulfamethoxazole-SMX) is frequently used in critically ill and immunocompromised patients. SMX is converted to N-acetyl-sulfamethoxazole (NASM) and excreted by the kidneys. NASM may form crystals in urine, especially in acid urine, that may induce a crystalline nephropathy. However, the imputability of crystals in acute kidney injury (AKI) has not been proven. We aimed to assess whether NASM crystals may promote AKI and to investigate risk factors associated with NASM crystalline nephropathy. Patients from Ile-de-France, France who developed AKI under SMX treatment introduced during hospitalization and had a crystalluria positive for NASM crystals were selected. Patients with excessive preanalytical delay for crystalluria or missing data regarding SMX treatment were excluded. We used the Naranjo score to assess the causal relationship between SMX and the development of AKI in patients with positive NASM crystalluria. Fourteen patients were included. SMX was the probable cause of AKI for 11 patients and a possible cause for 3 patients according to Naranjo score. Patients were exposed to high doses of SMX (but within recommended ranges), and most of them had a preexisting chronic kidney disease and were hypoalbuminemic. Urine pH was mildly acid (median 5.9). AKI occured more rapidly than expected after introduction of SMX (median 4 days) and recovered rapidly after drug discontinuation in most, but not all, cases. SMX is a probable cause of crystalline nephropathy. Monitoring of crystalluria in patients exposed to SMX may be of interest to prevent the development of crystalline nephropathy. Approval number of the study: BPD-2018-DIAG-008.

Case series summary: Four confirmed cases of xanthinuria in cats, and one suspected case based on pedigree analysis, were identified. Clinical presentations varied and included haematuria, pollakiuria, dysuria, and urethral and ureteral obstruction. All cats had upper urinary tract uroliths. Diagnosis was obtained through infrared mass spectrometry of uroliths or urine. Clinical signs commenced at 3–8 months of age and reduced in all cats in the medium to long term after the introduction of a protein-restricted diet. Four cats were castrated males and one was a spayed female. Cases consisted of four Munchkin pedigree cats and one unrelated domestic shorthair cat. All four affected Munchkin pedigree cats were related, with three cases full siblings and the fourth case a half-sibling. No connection to the Munchkin pedigree could be established for the domestic shorthair cat. A candidate causative genetic variant (XDH p.A681V) proposed for this cat was excluded in the Munchkin family. Relevance and novel information: All affected cats presented diagnostic challenges and routine urinalysis was insufficient to obtain a diagnosis. Cases of feline xanthinuria may be underdiagnosed due to situations where uroliths cannot be retrieved for analysis and there is an inability to make a diagnosis using crystal morphology alone on routine urinalysis. Metabolic screening of urine may provide an effective mechanism to confirm xanthinuria in suspected cases where uroliths are inaccessible or absent. In this case series, male cats were more common. Their anatomy may increase the risk of lower urinary tract signs and urethral obstruction developing secondary to xanthine urolithiasis. A protein-restricted diet appears to reduce clinical signs as part of long-term management. Plain language summary: Four closely related Munchkin cats and one domestic shorthair cat were found with a suspected genetic disease causing high levels of xanthine in their urine. The case series looks at similarities and differences in their clinical signs, as well as difficulties experienced in obtaining a correct diagnosis. All cats had upper urinary tract stones and required metabolic testing of the stones or urine to diagnose. All cats were young when their clinical signs started and were on a high-protein diet. Four cats were desexed males and one was a desexed female. A genetic variant that may have caused the disease in the domestic shorthair cat was ruled out in the Munchkin family. Cases of high xanthine levels in feline urine may be underdiagnosed as the stones may not be accessed for testing. In this case series, male cats were more common. Their anatomy may increase the risk of lower urinary tract signs. A protein-restricted diet appears to reduce clinical signs as part of long-term management. [ABSTRACT FROM AUTHOR]

The present study was conducted on 56 cats (49 males and 7 females) who presented with signs of feline lower urinary tract disease (FLUTD). Abdominal radiographs and ultrasounds, urinalysis, bacterial culture, and stone analysis were performed. Serum blood urea nitrogen (BUN) and creatinine were investigated. Urine sample analysis was investigated microscopically. The results indicated that the most common causes of lower urinary tract affections were urolithiasis (37.5%), followed by feline idiopathic cystitis (FIC) (33.9%), bacterial urinary tract infection (UTI) (14.2%), urethral plugs (10.7%) and neoplasia (3.5%). Urethral obstruction was (42.8%) more frequent in cats with urolithiasis, urethral plugs and FIC. Cats with FIC and urethral plugs were significantly younger than other diagnostic groups. Cats with urolithiasis and neoplasia had higher body weights than other FLUTD groups.Persian cats (39.5%) were the most affected breed. The mineral compositions in the analyzed uroliths were calcium oxalate (62.5%), struvite (50%) and ammonium urate (25%). FLUTD urine sediment crystalluria were triple phosphate struvite crystals (51.7%), calcium oxalate crystals (16.0%), and ammonium urate crystals (12.5%). FIC, urethral plugs and urolithiasis showed a significant increase in crystalluria and urethral obstruction. Urethral obstruction represented 42.8%, and it occurred frequently in cats with urolithiasis, urethral plugs and FIC. Post-renal azotemia with increased BUN and creatinine concentrations was detected in obstructive urolithiasis, urethral plugs and FIC. The identified bacterial cultures included Escherichia coli (37.5%), Staphylococcus aurous (37.5%) and Proteus species (25%). The results obtained from the study indicate that age, breed, sex and indoor confinement represent real challenges in developing lower urinary tract affections.

The present study was conducted on 56 cats (49 males and 7 females) who presented with signs of feline lower urinary tract disease (FLUTD). Abdominal radiographs and ultrasounds, urinalysis, bacterial culture, and stone analysis were performed. Serum blood urea nitrogen (BUN) and creatinine were investigated. Urine sample analysis was investigated microscopically. The results indicated that the most common causes of lower urinary tract affections were urolithiasis (37.5%), followed by feline idiopathic cystitis (FIC) (33.9%), bacterial urinary tract infection (UTI) (14.2%), urethral plugs (10.7%) and neoplasia (3.5%). Urethral obstruction was (42.8%) more frequent in cats with urolithiasis, urethral plugs and FIC. Cats with FIC and urethral plugs were significantly younger than other diagnostic groups. Cats with urolithiasis and neoplasia had higher body weights than other FLUTD groups. Persian cats (39.5%) were the most affected breed. The mineral compositions in the analyzed uroliths were calcium oxalate (62.5%), struvite (50%) and ammonium urate (25%). FLUTD urine sediment crystalluria were triple phosphate struvite crystals (51.7%), calcium oxalate crystals (16.0%), and ammonium urate crystals (12.5%). FIC, urethral plugs and urolithiasis showed a significant increase in crystalluria and urethral obstruction. Urethral obstruction represented 42.8%, and it occurred frequently in cats with urolithiasis, urethral plugs and FIC. Post-renal azotemia with increased BUN and creatinine concentrations was detected in obstructive urolithiasis, urethral plugs and FIC. The identified bacterial cultures included Escherichia coli (37.5%), Staphylococcus aurous (37.5%) and Proteus species (25%). The results obtained from the study indicate that age, breed, sex and indoor confinement represent real challenges in developing lower urinary tract affections. [ABSTRACT FROM AUTHOR]

The occurrence of hyperuricemia is frequently associated with diabetic ketoacidosis (DKA), however, crystalluria from the precipitation of calcium oxalate, uric acid, or urate crystals, is less known. Metabolic derangements during DKA, especially acidic urinary pH and hyperuricosuria are the main risk factors for uric acid crystals and stones. Here we report a case of uric acid crystalluria following the recovery phase of DKA.

This study aimed to assess the ability of rosmarinic acid (RA) to prevent kidney stone formation in an ethylene glycol and ammonium chloride (EG/AC) model. There was an increase in diuresis in the normotensive (NTRs) and hypertensive rats (SHRs) treated with hydrochlorothiazide (HCTZ) and exposed to EG/AC, while RA restored urine volume in NTRs. The EG/AC groups exhibited lower urine pH and electrolyte imbalance; these parameters were not affected by any of the treatments. Both HCTZ+EG/AC and RA+EG/AC reduced calcium oxalate crystal formation in NTR and SHR urine. Kidney tissue analysis revealed alterations in oxidative stress and inflammation parameters in all EG/AC-receiving groups, with RA enhancing antioxidant defenses in SHRs. Additionally, crystals were found in the kidney histology of all EG/AC-exposed groups, with reduced Bowman’s capsule areas in NTRs and SHRs. The NTR VEH+EG/AC group showed intense renal damage, while the others maintained their structures, where treatments with HCTZ and RA were fundamental for kidney protection in the NTRs. Docking analysis showed that RA exhibited good binding affinity with matrix metalloproteinase-9, phosphoethanolamine cytidylyltransferase, and human glycolate oxidase enzymes. The data disclosed herein underscore the importance of further research to understand the underlying mechanisms better and validate the potential of RA for clinical use.

Lower urinary tract problems were increasingly encountered in small animal practice. Urinary stones and crystals are common problems in these cases and are still a problem in cats and dogs. Dilution of urine or restriction of mineral intake is a way to reduce urolithiasis/crystalluria. Viburnum Opulus was prescribed as anti-urolitiatic in human medicine. The objective of this study was to evaluate the efficacy of Viburnum Opulus in urolithiasis or crystalluria in companion animals. For this purpose, 42 animals were presented with urinary system problems and diagnosed with urolithiasis or crystalluria, which were included in the study and divided into two main groups (21 calcium oxalate, 21 struvite) and two subgroups (Control and Study). The urinary score was noted as the presence of pollakiuria, crystals in the microscopic examination, hematuria, stranguria, proteinuria, leucocytes, and blood in the urine. The mean ages were 3.81 and 3.95 for the calcium oxalate and struvite groups, respectively. It was determined that the clinical urinary score of the calcium oxalate control group was 11.39 before the treatment and increased to 14.06 at the end of 2 weeks. However, it was observed that this score decreased from 10.71 to 8.71 in the calcium oxalate study group. In calcium oxalate-diagnosed animals, a decrease in clinical scores was significant in the Viburnum opulus group than in controls. The urinary scores decreased in both struvite subgroups, but no statistical differences were determined. All animals except the calcium oxalate control group were clinically healthy at the second visit. Using Viburnum opulus as an integrative medical approach will provide safe and effective treatment for urolithiasis/crystalluria. [ABSTRACT FROM AUTHOR]

Primary hyperoxaluria is the most severe stone disease responsible for multiple stone recurrence and impairment of kidney function. It is a rare inherited disease with an autosomal transmission. Due to the high proportion of consanguineous marriages by comparison to other areas in the world, this pathology is more frequent in North Africa. Stones are made of calcium oxalate monohydrate, which is not unique to the disease and cannot help physicians for the diagnosis. By contrast, stone morphology may be a useful marker of the pathology. We report our experience based on 614 stones from Moroccan children analyzed by infrared spectroscopy and examined by stereomicroscopy for the determination of their morphological type. Our results show that 85 stones (13.8%) exhibit a type Ic morphology, strongly suggestive of the disease in children patients. It was confirmed in all subjects of a subgroup of 43 patients who benefited from urinary biochemical explorations revealing whewellite crystalluria and a very high oxalate to creatinine ratio.

Raed M Almannie, Abdullah K Alsufyani, Abdullah U Alturki, Mana Almuhaideb, Saleh Binsaleh, Abdulaziz M Althunayan, Mohammed A Alomar, Khalid M Albarraq, Fahad A Alyami Division of Urology, Department of Surgery, College of Medicine and King Saud University Medical City, King Saud University, Riyadh, Saudi ArabiaCorrespondence: Abdullah K AlsufyaniDivision of Urology, Department of Surgery, King Saud University Medical City, King Saud University, Saudi Arabia, King Saud University, Riyadh, 11451, Saudi ArabiaTel +966114692731Fax +966114679493Email abdsuf@gmail.comPurpose: To investigate the relationship between urinary stone type and the type of crystals in the urine.Patients and Methods: This retrospective study involved 485 patients with urinary stones treated at King Saud University Medical City from May 2015 to June 2017. Clinical data were obtained from medical records. Different statistical analysis methods were applied, including basic contingency analysis, analysis of variance, logistic regression, discriminant analysis, partition modeling, and neural network evaluations.Results: Of 485 patients, 47 had crystals detected by urinalysis. The most common type of crystal was calcium oxalate (n = 31), which had the highest association with calcium oxalate stones. Uric acid crystals (n = 8) were associated with uric acid stones. The neural network model used for determining the sensitivity and specificity showed an R-square value of 0.88, with an area under the curve of 0.94 for calcium oxalate, 0.94 for carbonate apatite, and 1.0 for uric acid.Conclusion: The predictive algorithm developed in the present study may be used with a patient’s clinical parameters to predict the stone type. This approach predicts the stone types associated with certain patient characteristics with a high sensitivity and specificity, indicating that the models may be a valuable clinical tool in the diagnosis, management, and monitoring of stone diseases.Keywords: crystalluria, urinary sediment, neural network, urolithiasis, stone disease, urinary crystals

Drug induced kidney injury is a frequent adverse event which contributes to morbidity and increased healthcare utilization. Our current knowledge of drug induced kidney disease is limited due to varying definitions of kidney injury, incomplete assessment of concurrent risk factors and lack of long term outcome reporting. Electronic surveillance presents a powerful tool to identify susceptible populations, improve recognition of events and provide decision support on preventative strategies or early intervention in the case of injury. Research in the area of biomarkers for detecting kidney injury and genetic predisposition for this adverse event will enhance detection of injury, identify those susceptible to injury and likely mitigate risk. In this review we will present a 6R framework to identify and mange drug induced kidney injury - risk, recognition, response, renal support, rehabilitation and research.

Background and Objectives: Urolithiasis, commonly known as kidney stones, is a condition significantly impacted by dietary habits. The objective of this study is to evaluate the impact of a tailored dietary plan on the crystalluria and biological parameters of patients with different types of kidney stones over a 3-month period., Methods and Study Design: We conducted a prospective study of 3 months. The study involved patients with recurrent nephrolithiasis. Alongside the medical consultation, a comprehensive dietary survey was performed to assess the patients' nutritional habits. Urinary parameters, including volume, calcium, oxalate, uric acid, and power of hydrogen (pH), were evaluated both before and after the dietary intervention., Results: 69 patients were involved. There were 17 patients diagnosed with cystine lithiasis, 33 with oxalocalcic lithiasis and 19 with uric lithiasis. After 3 months, only 32 patients revisited for follow-up. There were significant changes ( p  = 0.002 and 0.04) in urine crystalluria for cystinic and uric lithiasis. For the urinary oxalate variation, there was a significant decrease from T1 (before dietary intervention) to T2 (after dietary intervention), with levels dropping from 0.289 ± 0.10 umol/l to 0.215 ± 0.079 umol/l ( p  = 0.02).Regarding urinary calcium (calciuria), there was a trend toward a decrease from T1 to T2, although the change was not statistically significant, with levels decreasing from 2.42 ± 1.68 umol/l to 2.14 ± 1.62 umol/l ( p  = 0.1)., Conclusions: Our research underscores the favorable effects of a tailored and well-balanced diet on both the crystalluria and biological parameters of individuals with recurrent lithiasis., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Urolithiasis is a common disease worldwide, but its causes are still not well understood. In many cases, crystalluria provides an early indication of urinary stone formation, and characterisation of the urinary deposits could help doctors to take early preventative measures to stop their further growth. Nowadays, the gold standard for the analysis of urinary deposits is optical microscopy, but the morphology-based information it provides can often be unreliable and incomplete, particularly for deposits with no defined crystalline structure. In response to the need of a more attested method, we used Raman spectroscopy to determine the chemical composition of urinary deposits and urinary stones of 15 patients with urolithiasis in order to find out whether direct correlation between the composition of the corresponding stones and the deposits exists. We found that the main chemical compounds typically constituting urinary stones also form the deposits and that their composition correlates in eleven out of fifteen cases. However, brushite deposits that we found in two cases did not result in brushite, but mixed calcium oxalate monohydrate and phosphate stones. Overall, Raman spectroscopy is an informative and reliable method that can be used for analysis of urinary sediments for early diagnosis of urinary stone formation.

Urolithiasis is a common disease worldwide, but its causes are still not well understood. In many cases, crystalluria provides an early indication of urinary stone formation, and characterisation of the urinary deposits could help doctors to take early preventative measures to stop their further growth. Nowadays, the gold standard for the analysis of urinary deposits is optical microscopy, but the morphology-based information it provides can often be unreliable and incomplete, particularly for deposits with no defined crystalline structure. In response to the need of a more attested method, we used Raman spectroscopy to determine the chemical composition of urinary deposits and urinary stones of 15 patients with urolithiasis in order to find out whether direct correlation between the composition of the corresponding stones and the deposits exists. We found that the main chemical compounds typically constituting urinary stones also form the deposits and that their composition correlates in eleven out of fifteen cases. However, brushite deposits that we found in two cases did not result in brushite, but mixed calciumoxalate monohydrate and phosphate stones. Overall, Raman spectroscopy is an informative and reliable method that can be used for analysis of urinary sediments for early diagnosis of urinary stone formation. [ABSTRACT FROM AUTHOR]

Acetazolamide (ACTZ) is a drug that is used frequently, especially in the treatment of glaucoma. It reduces the secretion of hydrogen in the proximal renal tubule and increases the elimination of bicarbonate and water. Its side effects include nausea, vomiting, abdominal pain, electrolyte imbalances. However, the cases of acute kidney injury (AKI) described are very rare. ACTZ is known to promote the formation of kidney stones due to its effects on urinary pH due to its chronic use, and when excreted in an acidic urinary environment, it can lead to the formation of crystals in the kidney tubules and cause kidney damage. Here we describe a rare case of acute kidney injury that required dialysis secondary to the use of low-dose acetazolamide after cataract surgery. AKI due to acute crystalluria is a potentially severe complication. With the description of this case, we want to emphasize the importance of knowing this rare adverse effect since an early diagnosis that requires high clinical suspicion can avoid complications. [ABSTRACT FROM AUTHOR]

A 5-y-old female bottlenose dolphin (Tursiops truncatus) from an aquarium in Japan had clinical signs of anorexia, vomiting, and bradykinesia. Enrofloxacin and lactated Ringer solution were administered for treatment of bacterial infection and for rehydration. Elevations of creatine kinase and aspartate aminotransferase activities were detected on day 4 of treatment, indicating that rhabdomyolysis had developed on day 3. On day 5, serum creatinine and urea concentrations increased and remained high throughout the remaining treatment; the dolphin died on day 16. Postmortem examination revealed massive necrosis of the longissimus dorsi muscles. Histologic examination revealed extensive necrosis of skeletal myofibers, multifocal renal tubular necrosis with intratubular casts and crystals, and suppurative bronchopneumonia. The renal casts labeled positively with anti-myoglobin antibody; expression of aquaporin-1 was decreased in renal tubules compared to normal kidney tissue. To our knowledge, this description of clinicopathologic findings of rhabdomyolysis leading to acute kidney injury with concomitant crystalline nephropathy has not been reported previously in a bottlenose dolphin. [ABSTRACT FROM AUTHOR]

Background: Carbonated beverages are very popular worldwide. Carbonated beverage consumption vast increase raises great health concerns regarding their effect on calcium homeostasis besides obesity and renal function. Carbonated beverages sugar content, caffeine, and acidulant all can affect in a way or another calcium absorption, metabolism and excretion. The latter has direct effect on teeth, bone and general wellbeing. This study aims to reveal the effect of sub-chronic intake of carbonated beverage on urinary pH, crystalluria, calcium excretion. Methods: 21 healthy volunteers have been recruited in this study (9 males and 12 females) abstain for any carbonated beverages for at least the previous 4 weeks before participating in this study. Urine has been collected over 24 hours, the next day each volunteer has to drink 250 ml of carbonated beverage (Pepsi®) daily for 3 weeks. On the last day, urine was collected again over 24hr. pH, crystalluria, and calcium in urine have been measured. Results: Urine pH and crystalluria after 3 weeks' intake of 250 ml of carbonated beverage did not statistically differ from urine pH before the intake. Although, there was a trend toward reduction in pH and an increase in crystalluria. Total calcium excretion in urine increase was statistically significant when compared with calcium excretion at the study beginning. Conclusion: The regular intake of carbonated beverage (Pepsi®) increase calcium excretion. Thus, it may be advisable to increase the intake of milk or other dairy product to overcome the adverse impact of carbonated beverages. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Nicaraguan sugarcane workers, particularly cane cutters, have an elevated prevalence of chronic kidney disease of unknown origin, also referred to as Mesoamerican nephropathy (MeN). The pathogenesis of MeN may include recurrent heat stress, crystalluria, and muscle injury with subsequent kidney injury. Yet, studies examining the frequency of such events in long-term, longitudinal studies are limited. METHODS: Using employment and medical data for male workers at a Nicaraguan sugarcane company, we classified months of active work as either work as a cane cutter or other sugarcane job and determined occurrence of dysuria, heat events and muscle events. Work months and events occurred January 1997 to June 2010. Associations between cane cutting and each outcome were analyzed using logistic regression based on generalized estimating equations for repeated events, controlling for age. RESULTS: Among 242 workers with 7257 active work months, 19.5% of person-months were as a cane cutter. There were 160, 21, and 16 episodes of dysuria, heat events, and muscle events, respectively. Compared with work months in other jobs, cane cutting was associated with an elevated odds of dysuria [odds ratio 2.40 (95% confidence interval 1.56–3.68)]. The number of heat and muscle events by cane cutter and other job were limited. CONCLUSIONS: Working as a cane cutter compared with other jobs in the sugarcane industry was associated with increased dysuria, supporting the hypothesis that cane cutters are at increased risk of events suspected of inducing or presaging clinically evident kidney injury.

Crystalluria is one of the most important factors contributing to the pathogenesis of urinary stones. The type of urinary crystals can be associated with urinary tract infection and subsequently alter urine pH. The aim of the present survey was to evaluate the frequency of crystalluria and bacteriuria in companion dogs of Ahvaz district. For this purpose, the urine of 101 healthy dogs was obtained by catheterization. Physical assessment was initially carried out for specific gravity, color, clearance and apparent characteristics, and then the biochemical analysis was performed to evaluate the presence of hemoglobin, glucose, protein, ketone bodies and urine pH was also measured. Urinary sediment was also evaluated for the presence of crystals, casts and cells. Urine samples were also examined for the presence of Staphylococcus, Proteus and Escherichia coli bacteria. Overall twenty cases (19.80%) had crystalluria; of which fifteen cases (75%) were struvite, two cases (10%) were oxalate calcium dehydrate, two cases (10%) mixture of struvite and oxalate-calcium dehydrate and one case (5%) mixture of oxalate calcium dehydrate and bilirubin. From a total of 101 samples, 40 cases (39.60%) had positive urine culture; of which sixteen cases (40%) were positive for Staphylococcus epidermidis and twelve (30%) for E. coli. Proteus was not isolated in any of the samples. There was no significant relationship between gender and breed with bacteriuria and crystalluria (p>0.05), but a significant difference was observed for age; with rising age resulting in increased crystalluria and bacteriuria (p

Summary: Background: Amoxicillin crystalluria (AC), potentially responsible for acute kidney injury (AKI), is reported more and more frequently in patients treated with high doses of intravenous amoxicillin (HDIVA). The main objective of this study was to evaluate AC incidence in these patients. The secondary objectives were to identify factors associated with AC and to evaluate its impact on the risk of AKI. Methods: This multicentre, observational, cohort study was conducted between Mar 18, 2014 and Aug 16, 2019 in Dijon, Nancy, and Reims University Hospitals as well as Châlon-sur-Saône, Charleville-Mézières, and Troyes general hospitals in France. Adult patients (≥18 years) treated with HDIVA and having been tested for AC at least once during treatment were included. Clinical, biological, and therapeutic characteristics of the patients were collected. A univariable mixed logistic regression model assessed the factors associated with AC. A multivariable Cox model with AC as a time-dependent variable assessed the prognostic factors for AKI. ClinicalTrials.gov number: NCT02853292. Findings: Of the 112 included patients, 27 (24.1%, 95% CI [16.2-32.0]) developed at least one episode of AC within a mean of 5.1 days. The factors associated with its occurrence were the concomitant use of angiotensin converting enzyme (ACE) inhibitors (OR=4.6, 95% CI [2.2-9.3], p

Introduction: Crystalluria is thought to be associated with kidney stone formation and can occur when urine becomes supersaturated with calcium, oxalate, and phosphate. The principal method used to identify urinary crystals is microscopy, with or without a polarized light source. This method can detect crystals above 1 μm in diameter (microcrystals). However, analyses of calcium oxalate kidney stones have indicated that crystallite components in these calculi are 50–100 nm in diameter. Recent studies have suggested that nanocrystals (

It is estimated that 29% of patients treated with sulfadiazine ultimately develop acute kidney failure. Diagnosis is based on urine sediment analysis.

Objectives Nicaraguan sugarcane workers, particularly cane cutters, have an elevated prevalence of chronic kidney disease of unknown origin, also referred to as Mesoamerican nephropathy (MeN). The pathogenesis of MeN may include recurrent heat stress, crystalluria, and muscle injury with subsequent kidney injury. Yet, studies examining the frequency of such events in long-term, longitudinal studies are limited. Methods Using employment and medical data for male workers at a Nicaraguan sugarcane company, we classified months of active work as either work as a cane cutter or other sugarcane job and determined occurrence of dysuria, heat events and muscle events. Work months and events occurred January 1997 to June 2010. Associations between cane cutting and each outcome were analyzed using logistic regression based on generalized estimating equations for repeated events, controlling for age. Results Among 242 workers with 7257 active work months, 19.5% of person-months were as a cane cutter. There were 160, 21, and 16 episodes of dysuria, heat events, and muscle events, respectively. Compared with work months in other jobs, cane cutting was associated with an elevated odds of dysuria [odds ratio 2.40 (95% confidence interval 1.56-3.68)]. The number of heat and muscle events by cane cutter and other job were limited. Conclusions Working as a cane cutter compared with other jobs in the sugarcane industry was associated with increased dysuria, supporting the hypothesis that cane cutters are at increased risk of events suspected of inducing or presaging clinically evident kidney injury. [ABSTRACT FROM AUTHOR]

• SbCO Index: paves kidney stone recurrence risk tool. • Key bacteria & gut microbiome's role in stone risk. • Enables microbiome-based therapy for kidney stones. Kidney stone disease, particularly those formed from calcium oxalate crystals, is a significant health challenge, especially in geographic regions with high recurrence rates, known as stone belt regions. Early and precise prediction of stone events is crucial for effective therapeutic intervention. We propose the 'Stool bacterial dysbiosis, Crystalluria, and Oxaluria (SbCO) Value Index,' a composite of three factors: the prevalence of Oxalate Metabolising Bacterial Species (OMBS) in stool, urine crystal examination, and oxalate content in urine, as a tool to quantify the risk of recurrent oxalate nephrolithiasis. Empirical data underscored a notable correlation between gut dysbiosis, crystalluria, and oxaluria. The absence of Oxalobacter formigenes was associated with an elevated recurrence risk. Known OMBS were detected in approximately 3–18% of the general population, with species such as Oxalobacter and Prevotella being identified as key contributors. A lower recurrence risk was observed in patients with high levels of O. formigenes , Lactobacillus , and Bifidobacterium. Conversely, low bacterial levels, combined with high crystalluria and oxaluria were linked to an increased recurrence risk. Our findings suggest the potential of the SbCO index for predicting recurrent kidney stones, highlighting the utility of interventional therapies, informed by targeted analyses of the gut microbiome, as well as urine crystals and metabolites, in managing oxalate nephrolithiasis. This approach could help to pave the way for personalized, microbiome-centered therapeutic strategies. [ABSTRACT FROM AUTHOR]

Acyclovir, an acyclic nucleoside, is commonly used for the treatment of viral infections. Acyclovir is well tolerated in children. However, severe nephrotoxicity has been shown to occur in some children. One of the mechanisms for acyclovir-induced nephrotoxicity is acyclovir-induced crystalluria. Prompt attention to urine microscopy examination can help avoid drug-induced nephrotoxicity. Here, we report a case of a seven-year-old febrile comatose child who received intravenous empirical acyclovir therapy and developed cloudy urine. Bedside urine microscopic examination shows fine-needle-shaped crystal. The urine was cleared within 12 h of stopping the acyclovir and adequate intravascular hydration. A child recovered without evidence of acute kidney injury.

BACKGROUND: Struvite crystals (Magnesium Ammonium Phosphate) are one of the most common causes of urolith formation in cats. Presence of these crystals in urea leads to urinary obstruction and idiopathic cystitis. The prevalence of urinary crystals has increased in recent years, thus there has been a growing interest in development of noninvasive, fast responsive therapies. Vitamin C is a safe compound with antioxidant properties. This vitamin is known as urine acidifier as well. Since struvite crystals are more soluble in acidic pH, it could be expected that vitamin C application could improve crystals dissolution as well as their disposal. It could also prevent other complications. OBJECTIVES: This study was designed to analyze the effects of vitamin C in reducing the rate and intensity of struvite crystals with current long term therapies such as diet alteration, acidifier’s applications and diuretics. METHODS: Ten male domestic cats with clinical signs of lower urinary tract disease were selected. Struvite crystalluria was confirmed by urine analysis and ultrasonography. Cats were divided to treatment and control groups each containing 5 cats. Both groups were treated by conventional therapies for two weeks, however, during the 1st week the treatment group received injectable vitamin C (100 mg/kg, every 24h, SC) and the control group received oral DL Methionine (200mg/cat, every 8h), in addition to conventional therapies. Urine was collected at days 0, 7 and 14 and its pH, specific gravity and number of crystals were calculated. Presence of floating echogenic foci was evaluated using ultrasound. RESULTS: Significant decrease in struvite crystalluria was observed in both groups. However, in group treated by vitamin C this decrease was faster and more effective. In addition, in case of obstruction, vitamin C showed better therapeutic effects. CONCLUSIONS: According to these results, vitamin C injection could be a therapeutic approach in treatment of urinary tract obstructions where fast response is needed to avoid further complications. Oral methionine seems to be a suitable choice for prophylaxis in patients with moderated signs and relatively high urine pH or continuing therapy to prevent recurrence of disease.

A 2-year-old male castrated domestic shorthair cat was presented for recommendations for dietary management of chronic FLUTD using a strictly plant-based diet as per the stipulations of the cat's owner. The cat had a history of urethral obstruction of unknown etiology, persistent marked struvite crystalluria, and persistent inappropriate elimination. Commercial plant-based products meeting the nutritional recommendations for maintenance of adult cats with the lowest concentration of struvite precursors were identified, but the cat would not eat them. At the request of the client, a homemade plant-based diet was formulated with the intention of increasing water intake and promoting acidic, dilute urine. Urine concentration was able to be decreased somewhat and struvite crystalluria resolved, but the urine remained more alkaline than intended. The cat clinically improved and no further FLUTD episodes were reported by the client.

The Consensus Group deliberated on a number of questions concerning urine and stone analysis over a period of months, and then met to develop consensus. The Group concluded that analyses of urine and stones should be routine in the diagnosis and treatment of urinary stone diseases. At present, the 24-h urine is the most useful type of urine collection, and accepted methods for analysis are described. Patient education is also important for obtaining a proper urine sample. Graphical methods for reporting urine analysis results can be helpful both for the physician and for educating the patient as to proper dietary changes that could be beneficial. Proper analysis of stones is also essential for diagnosis and management of patients. The Consensus Group also agreed that research has shown that evaluation of urinary crystals could be very valuable, but the Group also recognizes that existing methods for assessment of crystalluria do not allow this to be part of stone treatment in many places. [ABSTRACT FROM AUTHOR]

In this study, we present the first meta-analysis of human urine reported in the literature, drawing data from a total of 35 articles with a combined participant count of 14,021. Through this analysis, we have developed an artificial urine (AU) composition that can be adjusted within typical physiological parameters for in vitro applications. Our findings demonstrate the utility of this AU in determining the solubility of nitrofurantoin, particularly in the context of crystalluria. Notably, we observe that in saline, nitrofurantoin solubility, within the framework of its urinary pharmacokinetics, suggests a risk of crystalluria. However, in AU, this risk is mitigated due to complexation with urea. More broadly, we anticipate that our developed formulation will serve as a foundation for translational studies across biomedical and pharmaceutical sciences., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In February 2018, a 2-year-old American shorthair was treated conservatively for cystitis caused by crystalluria. However, as long as drug withdrawal was proceeding, the condition would be repeated, and the condition worsened since August. In order to diagnose and treat the sick cat, clinical examination, laboratory examination, X-ray, B-type ultrasound and other methods were used for diagnosis, and treatment was conducted according to the diagnosis results. The results showed that the cat was caused by ammoniomagnesium phosphate crystals blocking urethra, complicated with postrenal azotaemia and hyperkalemia. The relapse continued after conservative treatment, and the cat finally recovered by modifying urethra surgically. The results showed that the deficiency of drinking water, the change of urine pH, and high dietary magnesium and fiber content could promote the occurrence of the disease. For the problem of urethral obstruction that could not be solved by conservative treatment, operation was done to modify urethral stricture. [ABSTRACT FROM AUTHOR]

Background: canine urine is a complex fluid produced via glomerular filtration; it is useful for the elimination of waste substances. However‚ under specific physiological conditions certain minerals become supersaturated‚ leading to the precipitation of salts‚ resulting in crystalluria. These crystals may aggregate and form solid concretions‚ known as calculi or uroliths. The development and formation of these crystals are influenced by several risk factors‚ including breed‚ size‚ gender‚ age‚ diet‚ and urinary tract infections. Objective: to determine the prevalence of urinary crystals in canines and their association with risk factors in Santa Rosa de Cabal (SRC) and the metropolitan area of Pereira (MAP) (Risaralda‚ Colombia). Methods: a retrospective study was conducted using 3038 urinalysis results from dogs located in SRC and the MAP in Risaralda‚ analyzed by a reference laboratory in Pereira (EJELAB®) over a period of four years. The results were categorized based on breed‚ age‚ and gender. Statistical analysis includes a cross- tabulation‚ chi-square‚ Fisher’s exact test‚ and logistic regression to determine the prevalence (95 % CI) of urinary crystals and assess their association with various risk factors. Results: a 48.5 % (95 % CI = 46.7- 50.2) of the samples exhibited some crystalluria‚ with a nearly equal distribution between females (50.1 %) and males (49.9 %). Of these‚ 25 % were of mixed breed. Struvite crystals were found to be the most prevalent (78.5 %)‚ followed by oxalates (14.4 %) and urate (5.3 %). On average‚ females had a higher urinary pH level (7.49) than males (7.36). An increase of 1 pH unit was associated with a 12.24 times higher risk of developing struvite crystals. In addition‚ oxalates were related with the size of the dog‚ miniature breeds showed a higher risk‚ There was no association found between crystalluria and the factors of urine density and age. Conclusions: the estimated prevalence of crystalluria was considered high (48.5 %)‚ with struvite being the most common type of crystal. Finally‚ both the pH‚ and the size of the dog were identified as risk factors for crystal formation‚ with pH being the main factor. [ABSTRACT FROM AUTHOR]

Although many information has been published regarding canine urolithiasis, sensitivity of radiography, ultrasound and urinary parameters have been poorly correlated with number, size, and composition of the stones. One hundred and thirteen clinical files of dogs with diagnosis of urolithiasis were retrospectively selected. Information regarding number, appearance, location, size, and composition of the stones were noted after surgical removed. Urolithiasis data was compared with radiographs and ultrasound images and urinalysis parameters. Pure struvite was found in 42.4% and calcium oxalate in 35.6%. Survey radiographs enabled the detection of radiopaque stones and when an ultrasound examination was also performed, the sensitivity was increased. Double contrast radiography enabled identification in 100% of radiolucent stones, and allowed for size measurement and number counts in 76.9% of radiolucent stones. Crystalluria had low sensitivity (31.5%) and specificity (58.8%). Hematuria (96.3%) and leukocyturia (61.1%) were the most common parameters found. We concluded that double contrast radiography can be considered the method of choice for detection of radiolucent stones. Crystalluria is not a good parameter to detect or predict type of stone. Hematuria and leukocyturia, although non-specific findings, can be used as triage for investigation of urolithiasis.

Urolithiasis is a common urological disease the prevalence of which tends to increase. The main targets of therapy for patients with uric acid nephrolithiasis include normalization of purine metabolism, dissolution of stones, and prevention of stone formation. Oral administration of a citrate mixture or sodium bicarbonate results in urine alkalinization and dissolution of the uric acid stone. The article demonstrates the results of the recent Russian studies of the efficacy and safety of litholytic therapy for uric acid nephrolithiasis both as monotherapy and in combination with remote lithotripsy. The studies show that citrate therapy is a highly effective, non-invasive method for the treatment and metaphylaxis of uric acid nephrolithiasis.

Competing Interests: The authors declared no conflict of interest.

Objectives: The aim of the study was to identify any dietary, signalment, geographic and clinical factors associated with hematuric struvite crystalluria (HSC) in a population of cats that visit general care veterinary hospitals in the USA. Methods: In total, 4032 cats that had a first-time diagnosis of HSC and 8064 control cats with no history of hematuria or crystalluria were identified from medical records of all cats examined between 2007 and 2011 at 790 US veterinary hospitals. Extracted variables included age, sex, neuter status, breed, diet, urinalysis results and history of cystitis. Potential associations between these variables and HSC were estimated. Results: Controlling for other factors, young cats fed a dry diet had an increased likelihood of HSC relative to young cats fed a non-dry diet. However, as age increased, the likelihood of HSC declined for cats fed a dry diet and increased for cats fed a non-dry diet. Moreover, the odds of HSC were significantly greater when cats were unneutered (vs neutered; odds ratio [OR] 45.52) or had a thin (vs heavy) body condition (OR 23.81), diagnosis of cystitis (OR 2.84), urine protein concentration >30 mg/dl (OR 4.72), alkaline (vs neutral) urine pH (OR 3.34), pyuria (OR 23.67) or bacteriuria (OR 2.24). Conclusions and relevance: The present study provides estimates of the strengths of association between HSC and certain signalment and clinical characteristics of cats. This information could help clinicians to perform a more directed screening for struvite crystalluria in certain cat populations. Follow-up studies that build on the findings of this study could explore the clinical importance of HSC in cats. [ABSTRACT FROM AUTHOR]

Adenine phosphoribosyltransferase (APRT) deficiency is a rare autosomal recessive disorder of adenine metabolism that results in excessive urinary excretion of the poorly soluble 2,8-dihydroxyadenine (DHA), leading to kidney stones and chronic kidney disease. The purpose of this study was to assess urinary DHA excretion in patients with APRT deficiency, heterozygotes and healthy controls, using a recently developed ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) assay. Patients enrolled in the APRT Deficiency Registry and Biobank of the Rare Kidney Stone Consortium (http://www.rarekidneystones.org/) who had provided 24-h and first-morning void urine samples for DHA measurement were eligible for the study. Heterozygotes and healthy individuals served as controls. Wilcoxon-Mann-Whitney test was used to compare 24-h urinary DHA excretion between groups. Associations were examined using Spearman's correlation coefficient (r s). The median (range) 24-h urinary DHA excretion was 138 (64–292) mg/24 h and the DHA-to-creatinine (DHA/Cr) ratio in the first-morning void samples was 13 (4–37) mg/mmol in APRT deficiency patients who were not receiving xanthine oxidoreductase inhibitor therapy. The 24-h DHA excretion was highly correlated with the DHA/Cr ratio in first-morning void urine samples (r s = 0.84, p <.001). DHA was detected in all urine samples from untreated patients but not in any specimens from heterozygotes and healthy controls. High urinary DHA excretion was observed in patients with APRT deficiency, while urine DHA was undetectable in heterozygotes and healthy controls. Our results suggest that the UPLC-MS/MS assay can be used for diagnosis of APRT deficiency. [ABSTRACT FROM AUTHOR]