Crystalluria

AbstractCrystalluria 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.

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Development of a Portable Multi-Sensor Urine Test and Data Collection Platform for Risk Assessment of Kidney Stone Formation

Electronics ◽

10.3390/electronics9122180 ◽

2020 ◽

Vol 9 (12) ◽

pp. 2180

Author(s):

Wen-Yaw Chung ◽

Roozbeh Falah Ramezani ◽

Angelito A. Silverio ◽

Vincent F. Tsai

Keyword(s):

Risk Assessment ◽

Uric Acid ◽

Data Collection ◽

Stone Formation ◽

Urinary Stone ◽

Measurement Range ◽

Urine Ph ◽

System Validation ◽

Stone Former ◽

And Gender

In this paper, we present an Internet of things (IoT)-based data collection system for the risk assessment of urinary stone formation, or urolithiasis, by the measurement and storage of four parameters in urine: pH, concentrations of ionized calcium (Ca2+), uric acid and total dissolved solids. The measurements collected by the system from patients and healthy individuals grouped by age and gender will be stored in a cloud database. These will be used in the training phase of an artificial intelligence (AI) machine learning process utilizing the logistics regression model. The trained model provides a binary risk assessment, indicating if the end user is either a stone-former or not. For system validation, standard chemical solutions were used. Preliminary results indicated a sufficient measurement range, falling within the physiological range, and resolution for pH (2.0–10.0, +/−0.1), Ca2+(0.1–3.0 mmol/l, +/−0.05), uric acid (20–500 ppm, +/−1) and conductivity (1.0–40.0 mS/cm, +/−0.1), exhibiting high correlation with standard instruments. We intend to deploy this system in few hospitals in Taiwan to collect the data of patients’ urine, with analysis aided by urologist assessments for the risk of urolithiasis. The modularized design allows future modification and expansion to accommodate other sensing analytes.

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PD51-12 LOW URINE PH AND ASSOCIATED HYPOCITRATURIA ARE RISK FACTORS FOR URINARY STONE FORMATION IN ELDERLY STONE PATIENTS

The Journal of Urology ◽

10.1016/j.juro.2015.02.1772 ◽

2015 ◽

Vol 193 (4S) ◽

Author(s):

Young-Won Kim ◽

Sung Pil Seo ◽

Yunbyung Chae ◽

In-Chang Cho ◽

Hoon Jang ◽

...

Keyword(s):

Risk Factors ◽

Stone Formation ◽

Urinary Stone ◽

Urine Ph

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Proteus mirabilis Urease: Unsuspected Non-Enzymatic Properties Relevant to Pathogenicity

International Journal of Molecular Sciences ◽

10.3390/ijms22137205 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7205

Author(s):

Matheus V. C. Grahl ◽

Augusto F. Uberti ◽

Valquiria Broll ◽

Paula Bacaicoa-Caruso ◽

Evelin F. Meirelles ◽

...

Keyword(s):

Proteus Mirabilis ◽

Stone Formation ◽

Cell Types ◽

Bioinformatic Analysis ◽

Urinary Stone ◽

Enzymatic Properties ◽

Hek293 Cells ◽

Urinary Stones ◽

Isolated Cells ◽

Tnf Α

Infection by Proteus mirabilis causes urinary stones and catheter incrustation due to ammonia formed by urease (PMU), one of its virulence factors. Non-enzymatic properties, such as pro-inflammatory and neurotoxic activities, were previously reported for distinct ureases, including that of the gastric pathogen Helicobacter pylori. Here, PMU was assayed on isolated cells to evaluate its non-enzymatic properties. Purified PMU (nanomolar range) was tested in human (platelets, HEK293 and SH-SY5Y) cells, and in murine microglia (BV-2). PMU promoted platelet aggregation. It did not affect cellular viability and no ammonia was detected in the cultures’ supernatants. PMU-treated HEK293 cells acquired a pro-inflammatory phenotype, producing reactive oxygen species (ROS) and cytokines IL-1β and TNF-α. SH-SY5Y cells stimulated with PMU showed high levels of intracellular Ca2+ and ROS production, but unlike BV-2 cells, SH-SY5Y did not synthesize TNF-α and IL-1β. Texas Red-labeled PMU was found in the cytoplasm and in the nucleus of all cell types. Bioinformatic analysis revealed two bipartite nuclear localization sequences in PMU. We have shown that PMU, besides urinary stone formation, can potentially contribute in other ways to pathogenesis. Our data suggest that PMU triggers pro-inflammatory effects and may affect cells beyond the renal system, indicating a possible role in extra-urinary diseases.

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The Impact of Diet on Urinary Risk Factors for Cystine Stone Formation

Nutrients ◽

10.3390/nu13020528 ◽

2021 ◽

Vol 13 (2) ◽

pp. 528

Author(s):

Roswitha Siener ◽

Norman Bitterlich ◽

Hubert Birwé ◽

Albrecht Hesse

Keyword(s):

Risk Factors ◽

Dietary Habits ◽

Sodium Intake ◽

Stone Formation ◽

Dietary Treatment ◽

Vegetarian Diet ◽

Dietary Sodium ◽

Urine Ph ◽

Cystine Stone ◽

The Impact

Despite the importance of dietary management of cystinuria, data on the contribution of diet to urinary risk factors for cystine stone formation are limited. Studies on the physiological effects of diet on urinary cystine and cysteine excretion are lacking. Accordingly, 10 healthy men received three standardized diets for a period of five days each and collected daily 24 h urine. The Western-type diet (WD; 95 g/day protein) corresponded to usual dietary habits, whereas the mixed diet (MD; 65 g/day protein) and lacto-ovo-vegetarian diet (VD; 65 g/day protein) were calculated according to dietary reference intakes. With intake of the VD, urinary cystine and cysteine excretion decreased by 22 and 15%, respectively, compared to the WD, although the differences were not statistically significant. Urine pH was significantly highest on the VD. Regression analysis showed that urinary phosphate was significantly associated with cystine excretion, while urinary sulfate was a predictor of cysteine excretion. Neither urinary cystine nor cysteine excretion was affected by dietary sodium intake. A lacto-ovo-vegetarian diet is particularly suitable for the dietary treatment of cystinuria, since the additional alkali load may reduce the amount of required alkalizing agents.

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Crystallization theory relating to urinary stone formation

World Journal of Urology ◽

10.1007/bf00326900 ◽

1983 ◽

Vol 1 (3) ◽

pp. 131-137 ◽

Cited By ~ 13

Author(s):

G. H. Nancollas

Keyword(s):

Stone Formation ◽

Urinary Stone

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Nutrition and Kidney Stone Disease

Nutrients ◽

10.3390/nu13061917 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1917

Author(s):

Roswitha Siener

Keyword(s):

Kidney Stone ◽

Fluid Intake ◽

Stone Formation ◽

Urinary Stone ◽

Stone Disease ◽

Urinary Stones ◽

Dietary Therapy ◽

Effective Prevention ◽

Kidney Stone Disease ◽

Nutrition And Diet

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.

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