[Current concepts on the pathogenesis of urinary stones]

Zn2+ regulates human oxalate metabolism by manipulating oxalate decarboxylase to treat calcium oxalate stones

A high concentration of oxalate is associated with an increased risk of kidney calcium oxalate (CaOx) stones, and the degradation of exogenous oxalate mostly depends on oxalate-degrading enzymes from the intestinal microbiome. We found that zinc gluconate supplement to patients with CaOx kidney stones could significantly improve the abundance of oxalate metabolizing bacteria in humans through clinical experiments on patients also subjected to antibiotic treatment. The analysis of clinical samples revealed that an imbalance of Lactobacillus and oxalate decarboxylase (OxDC) was involved in the formation of CaOx kidney stones. Then, we identified that Zn²⁺ could be used as an external factor to improve the activity of OxDC and promote Lactobacillus in the intestinal flora, and this treatment achieved a therapeutic effect on rats with stones aggravated by antibiotics. Finally, by analyzing the three-dimensional structure of OxDC and completing in vitro experiments, we propose a model of the Zn²⁺-induced reduction of CaOx kidney stone symptoms in rats by increasing the metabolism of oxalate through the positive effects of Zn²⁺ on Lactobacillus and OxDC.

Dose-dependant preventive effect of a herbal compound on crystal formation in rat model

INTRODUCTION

To analyze the dose-dependent preventive effect of a plant-based herbal product on the new crystal formation in a rat model.

MATERIALS AND METHODS

A total of 42 rats were divided into 7 groups and zinc discs were placed into the bladder of rats to provide a nidus for the development of new crystal formation: Group 1: control, Group 2: 0.75 percent ethylene glycol (EG); Group 3: 0.75 percent EG plus 0.051 ml of the compound; Group 4: 0.75 percent EG plus 0.179 ml of the compound; Group 5: 0.75 percent EG plus 0.217 ml of the compound; Group 6: 0.75 percent EG plus 0.255 ml of the compound; Group 7 0.75 percent EG plus 0.332 of the compound). The analysis and comparison focused on the disc weights, changes in urinary oxalate and calcium levels, urinary pH, and the histopathologic evaluation of the inflammatory changes in the bladder after 14 days.

RESULTS

According to the evaluation of discs placed in the bladders of the animals, animals receiving the herbal compound on a dose-dependent basis showed a limited increase in the disc weights values after 14 days, despite a considerable increase in animals receiving EG alone (p = 0.001). Further evaluation of the increase in disc weights on a dose-dependent basis in different subgroups (from Groups 3 to 7) demonstrated that the limitation of crystal deposition began to be more prominent as the dose of herbal compound increased. This effect was more evident particularly in comparisons between group 7 and others, according to LSD multiple comparison tests (p = 0.001). As anticipated, there has been no discernible change in the weight of the discs in the control group. Although urinary calcium levels in animals of Groups 2, 6, and 7 were significantly higher than the other groups, we were not able to demonstrate a close correlation between urinary oxalate levels and the increasing dose levels. Even though mean urine pH levels were statistically considerably higher in Group 3, there was no statistically significant correlation between the oxalate and calcium levels between all groups, and no association was seen with the administration of herbal agents. The transitional epithelium between the three groups of animals' bladder samples did not exhibit any appreciable difference according to pathological analysis.

CONCLUSIONS

In this animal model, the treatment of the compound was successful in lowering the amount of crystal deposition surrounding the zinc discs, most noticeably at a dosage of 0.332 ml, three times per day.

The Clinical Efficacy and Safety of Extracorporeal Shock Wave Lithotripsy in the Treatment of Patients with Urinary Calculi

Objective

To evaluate the clinical efficacy of extracorporeal shock wave lithotripsy (ESWL) for urinary calculi and precautions of postoperative complications.

Methods

90 patients with urinary calculi at our hospital were randomly recruited between July 2019 and July 2020 and were allocated (1 : 1) to receive either ESWL (observation group) or conventional surgery (control group). Clinical efficacy was the primary endpoint, whereas adverse events were the secondary endpoint.

Results

The operation time, early activity time, and hospitalization time of the observation group were significantly lower than those of the control group (P < 0.05). ESWL resulted in less postoperative pain in patients versus conventional surgery (P < 0.05). ESWL was associated with a significantly higher total clinical efficacy (97.78%) versus conventional surgery (82.22%) (P < 0.05). The eligible patients given ESWL had a lower incidence of complications (11.12%) versus those given conventional surgery (31.12%) (P < 0.05).

Conclusion

Hematuria prevention requires precise localization of stones as well as adjustment of pulse energy and the number of impacts due to stone changes. Precautions against renal colic necessitate complete comminution of stones intraoperatively, more postoperative water intake, moderate exercise, or injection of antispasmodic drugs and cathartics for pain relief. Nausea and vomiting precautions require preoperative recording of previous medical history and corresponding treatment, intraoperative real-time adjustment of voltage pulse frequency, and duration depending on the magnitude of intraoperative reaction. Urinary tract infection prevention requires preoperative prevention and proper postoperative anti-infection and anti-inflammatory treatment, along with enough water intake and bed rest. Other precautions include thorough comminution of the calculi, proper anti-infection and anti-inflammatory treatment, no early exercise or excessive activity after surgery, and proper postoperative care. ESWL is effective in treating patients with urinary calculi with a simple, safe, and quick operation and a low incidence of adverse events, as it effectively reduces the incidence of complications, accelerates the recovery of patients and improves their quality of life.

iTRAQ-Based Comparative Proteomics Analysis of Urolithiasis Rats Induced by Ethylene Glycol

Nephrolithiasis is a frequent chronic urological condition with a high prevalence and recurrence rate. Proteomics studies on urolithiasis rat models are highly important in characterizing the pathophysiology of kidney stones and identifying potential approaches for preventing and treating kidney stones. The isobaric tags for relative and absolute quantification (iTRAQ) were performed to identify differentially expressed proteins (DEPs) in the kidney between urolithiasis rats and control rats. The results showed that 127 DEPs (85 upregulated and 42 downregulated) were identified in urolithiasis and control rats. The functions of DEPs were predicted by Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interaction (PPI) network analysis. The expression of four upregulated proteins (Tagln, Akr1c9, Spp1, and Fbn1) and four downregulated proteins (Hbb, Epb42, Hmgcs2, and Ca1) were validated by parallel reaction monitoring (PRM). Proteomics studies of ethylene glycol-induced urolithiasis rat models using iTRAQ and PRM helped to elucidate the molecular mechanism governing nephrolithiasis and to identify candidate proteins for the treatment of kidney stones.

Extraction of giant bladder calcium oxalate stone: A case report

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Hyperoxaluria, hypercalciuria and a low urine calcium–oxalate ratio are involved in calcium oxalate monohydrate stone.

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For large-sized bladder stones, all the reports have recommended open cystolithotomy.

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Hyperoxaluria, and low urinary pH may promote the stone formation.

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Containment of animal protein and salt can reduce the relative risk of stone.

Introduction

Bladder stone is a rare and ancient disease. Nowadays new technologies have been developed in the effort to make less invasive stone treatment. Bladder calculi account for 5% of urinary calculi.

Presentation of case

A 52-year-old male patient with symptoms of lower abdominal pain, dysuria and pollakiuria was admitted. Urinalysis showed that pH5.0 and presence of calcium oxalate crystals and leukocyturia but erthrocyturia and nitrite were absent. Abdominal ultrasonogry revealed hydronephrosis, thickened bladder wall and large single stone. Plain radiography showed a large bladder stone measuring 12 × 10 cm.

Discussion

In our case 1 extremely large bladder calculus occupied most of the bladder and pressing on the orifices of the ureters, leading to the presence of hydronephrosis. For large-sized bladder stones, all the reports have recommended open cystolithotomy.

Conclusion

The combination of improved nutrition and modern antibiotic treatment has to be led to the frequency of bladder lithiasis. Calcium intake shouldn’t be restricted, whereas oxalate, sodium, and protein intakes have to be limited.