Kidney stone is a highly recurrent disease in the urinary tract system. Most kidney stones are calcium stones, usually consisting of either calcium oxalate or calcium phosphate. Supersaturation of soluble calcium, oxalate, phosphate, and citrate in the urine is the basis for calcium stone formation. Genetics, diet, low physical activity, and individual habits contribute to the formation of kidney stones. In this review, the associations of the risk of kidney stones with oxalate consumption and some individual habits, such as smoking, alcohol drinking, and opium consumption, are summarized.
Humans ; Calcium/urine* ; Oxalates ; Kidney Calculi/urine* ; Calcium Oxalate/urine* ; Habits

Kidney stone is one of the common diseases of the urinary system. About 80% of kidney stones are mainly composed of calcium oxalate. As a huge bacterial network, the interaction of gut microbes is complex. Intestinal microbes may play a role in the pathogenesis and prevention of kidney stones. The intestinal flora of patients with calcium oxalate stones possess unique distribution of gut microbes.
Calcium Oxalate ; Gastrointestinal Microbiome ; Humans ; Kidney Calculi/etiology* ; Oxalobacter formigenes ; Urinary Calculi

In 2018, external quality assessment trials for urinalysis and fecal occult blood (FOB) were performed using 1,590 participants. Urine chemistry tests were performed thrice while urine sediment and FOB tests twice. Urine chemistry tests comprised of pH, protein, glucose, ketone body, bilirubin, blood, urobilinogen, nitrite, leukocyte, and specific gravity analyses. The results of urine chemistry and specific gravity tests showed accuracy rates >95%, except for the pH test. The accuracy rate of urine sediments was low, especially for atypical calcium oxalate crystal and red blood cell cast. In the FOB quality test, reagents showed accuracy rates >90%, except for SD and GC Genedia FOB reagents. In the FOB quantitative test, Alfresa NS-Plus C instrument showed falsely high values in the FOB negative specimens.
Bilirubin ; Calcium Oxalate ; Chemistry ; Erythrocytes ; Glucose ; Hydrogen-Ion Concentration ; Indicators and Reagents ; Leukocytes ; Occult Blood ; Quality Control ; Specific Gravity ; Urinalysis ; Urobilinogen

Objective: To explore the etiological factors for calculus-associated seminal vesiculitis by analyzing the composition of seminal vesicle calculus samples. METHODS: This retrospective study included 6 cases of recurrent hematospermia diagnosed with seminal vesicle calculus by non-contrast pelvic CT. The patients were aged 28 to 69 years, with persistent or recurrent hematospermia for 3 months to 6 years, and 5 of them with a history of acute urethritis. All the patients underwent seminal vesiculoscopy, which confirmed calculus-associated seminal vesiculitis. The calculus samples were obtained with a spiral dislodge and their composition was determined with a second-generation infrared calculus composition analyzer. The patients were followed up for 2 to 12 weeks postoperatively, during which non-contrast pelvic CT was employed for observation of recurrent calculus in the reproductive tract. RESULTS: Pelvic CT scanning indicated recurrence of seminal vesicle calculus in 3 cases at 12 weeks postoperatively, of which, 2 were accompanied with recurrent hematospermia, both observed at 4 weeks after operation. As for the composition of the calculus, the infrared calculus composition analyzer revealed struvite (magnesium ammonium phosphate hexahydrate) in 5 cases and a mixture of calcium oxalate dihydrate, calcium oxalate monohydrate, and carbonate apatite in the other one. CONCLUSIONS Seminal vesicle calculi are most commonly composed of struvite, and infection is the main etiological factor for calculus-associated seminal vesiculitis.
Adult ; Aged ; Apatites ; analysis ; Calcium Oxalate ; analysis ; Calculi ; chemistry ; complications ; diagnostic imaging ; Genital Diseases, Male ; diagnostic imaging ; etiology ; Hemospermia ; etiology ; Humans ; Male ; Middle Aged ; Postoperative Period ; Recurrence ; Retrospective Studies ; Seminal Vesicles ; diagnostic imaging ; Struvite ; analysis ; Tomography, X-Ray Computed ; Urethritis ; etiology

To analyze types of urinary calculi and patients' clinical characteristics, and to explore the strategies for prevention and treatment of urinary calculi.
 Methods: A total of 1 849 patients with urinary calculi were treated in the Department of Urology, the Third Xiangya Hospital of Central South University. The components were analyzed by infrared spectroscopy. The relationship between stone composition and clinical parameters was analyzed according to the clinical characteristics of the patients.
 Results: The proportion of calcium oxalate stone or uric acid stone in male (84.1% or 7.7%) was higher than that in female (78.4% or 4.2%). The older patients were more likely to be diagnosed as uric acid stone. The proportions of uric acid stone in patients <18 years old, 18-<41 years old, 41-<66 years old, and ≥66 years old were 0.0%, 1.6%, 6.6%, and 12.4%, respectively. There was no significant difference in the proportion of stones in patients with different BMI. There were no significant difference in the stone composition between the patients with or without urinary tract infection, hypertension or diabetes. The proportion of uric acid stones in patients with acidic urine was higher than the other types. The proportion of uric acid stones in patients with elevated creatinine (12.1%) was higher than that in the patients with normal creatinine (4.5%).
 Conclusion: Elderly patients, or patients with high uric acid and renal insufficiency are more prone to uric acid stones. Regulation of urinary pH may be an important strategy for preventing and treating urinary calculi in Hunan Province.
Adolescent ; Adult ; Age Factors ; Aged ; Body Mass Index ; Calcium Oxalate ; analysis ; Creatinine ; urine ; Female ; Humans ; Hydrogen-Ion Concentration ; Kidney Calculi ; chemistry ; therapy ; Male ; Middle Aged ; Sex Factors ; Spectrophotometry, Infrared ; Uric Acid ; analysis ; Urinary Calculi ; chemistry ; therapy ; urine

No abstract available.
Bone Marrow/*metabolism/pathology ; Calcium Oxalate/chemistry/metabolism ; Humans ; Hyperoxaluria/*etiology ; Kidney Calculi/etiology ; Male ; Middle Aged ; Nephrectomy/*adverse effects ; Pancytopenia/*pathology ; Recurrence ; Renal Insufficiency/etiology ; Thyrotropin/blood

The incidence of kidney stones is common in the United States and treatments for them are very costly. This review article provides information about epidemiology, mechanism, diagnosis, and pathophysiology of kidney stone formation, and methods for the evaluation of stone risks for new and follow-up patients. Adequate evaluation and management can prevent recurrence of stones. Kidney stone prevention should be individualized in both its medical and dietary management, keeping in mind the specific risks involved for each type of stones. Recognition of these risk factors and development of long-term management strategies for dealing with them are the most effective ways to prevent recurrence of kidney stones.
Calcium Oxalate ; Diagnosis ; Epidemiology ; Humans ; Hypercalciuria ; Hyperoxaluria ; Incidence ; Kidney Calculi* ; Kidney* ; Nephrolithiasis ; Recurrence ; Risk Factors ; United States

In the study, the inhibitory effect of epigallocatechin gallate (EGCG) on Calcium oxalate nephrolithiasis and its possible mechanism were investigated. The rat Calcium oxalate nephrolithiasis model was induced through the combined oral administration of ethylene glycol and ammonium chloride, which was intervened with EGCG. Rat blood samples were collected to detect blood creatinine (Cr), blood urea nitrogen (BUN) and blood calcium. Rat urine samples were collected to observe and compare 24-hour urine volume, oxalic acid (Ox) and calcium in urine. Renal samples were collected to prepare tissue slices and observe the pathological changes in Calcium oxalate nephrolithiasis. The expression of osteopontin (OPN) in renal tissues was evaluated by Real-time PCR and Western blot. According to the results, compared with normal rats, rats in the nephrolithiasis model showed significant increases in Cr, BUN, urine Calcium, urine Ox and renal OPN expression (P < 0.05), but obvious decrease in 24-hour urine volume (P < 0.05); Compared with rats with nephrolithiasis, those processed with EGCG revealed remarkable declines in Cr, BUN, urine Calcium and urine Ox (P < 0.05), with significant rise in 24-hour urine volume (P < 0.05) in a concentration-dependent manner. Additionally, compared with the control group, nephrolithiasis rats showed significant pathological changes in Calcium oxalate calculus. After ECCG treatment, the renal pathological changes and OPN expression attenuated significantly in a concentration-dependent manner. The results showed that EGCG inhibits the formation of calcium oxalate nephrolithiasis in rats and shows a notable protective effect on renal functions.
Animals ; Blood Urea Nitrogen ; Calcium ; blood ; Calcium Oxalate ; metabolism ; Catechin ; administration & dosage ; analogs & derivatives ; Creatinine ; blood ; Disease Models, Animal ; Humans ; Kidney ; drug effects ; metabolism ; Male ; Nephrolithiasis ; blood ; drug therapy ; genetics ; Osteopontin ; genetics ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo establish a method of high-performance liquid chromatography (HPLC) for determining the urine oxalate levle in rats with renal calcium oxalate calculus.

METHODSTotally 24 SPF Wistar healthy male rats were randomly divided into control group(n=12)and ethylene glycol (EG) group (n=12). Rats in EG group were administered intragastrically with 2% ammonium chloride (AC)2 ml/rat per day+1% ethylene glycol (EG), along with free access to drinking water.The control group was fed with deionized water, along with the intragastric administration of normal saline (1 ml per day). Twenty-eight days after modelling, the 24-hour urine samples were collected, and the urine oxalic acid levels were determined using HPLC and the results were compared with those of catalytic spectrophotometry using oxidation of methyl. During the HPLC, the samples were separated on Aglient 5TC-C18 (250×4.6 mm,5 Μm), eluted with mixture of methanol (0.1 mol/L) and ammonium acetate (15:85) at 1.2 ml/min, and detected at 314 nm, with the column temperature being 20 ℃.

RESULTSThe standard curves of high and low concentrations of oxalic acid were y=5909.1x+378730, R² =0.9984 and y=7810.5x-16635, R² =0.9967,respectively. The lowest detectable concentration in this method was 5 Μg/ml. The linear high concentration range of oxalate stood at 62.50-2000.00 Μg/ml, and the linear low concentration range of oxalate stood at 6.25-100.00 Μg/ml. Its average recovery was 95.1%, and its within-day and day-to-day precisions were 3.4%-10.8% and 3.8%-9.4%. Both HPLC and catalytic spectrophotometry showed significantly higher urinary oxalic acid concentration and 24 h urine oxalate level in EG group compared with the control group [urinary oxalic acid concentration: (736.35 ± 254.52) Μg/ml vs.(51.56 ± 36.34) Μg/ml,(687.35 ± 234.53) Μg/ml vs.(50.24 ± 42.34) Μg/ml;24 h urine oxalate level: (11.23 ± 4.12)mg vs.(0.87 ± 0.45)mg,(9.89 ± 3.55)mg vs. (0.77 ± 0.65)mg; all P<0.01]. No statistically significant difference was observed in the results of urinary oxalate concentration and 24 h urine oxalate level between HPLC and potassium chromate oxidation of methyl red spectrophotometry (all P>0.05).

CONCLUSIONHPLC is a simple, rapid, and precise method in detecting urine oxalate level in rats with renal calcium oxalate calculus, with high recovery rate.

Acetates ; Animals ; Azo Compounds ; Calcium Oxalate ; Calculi ; Chromates ; Chromatography, High Pressure Liquid ; Kidney ; Male ; Oxalates ; Potassium Compounds ; Rats ; Rats, Wistar ; Spectrophotometry ; Water

PURPOSE: To assess the potential of dual-energy computed tomography (DECT) to identify urinary stone components, particularly uric acid and calcium oxalate monohydrate, which are unsuitable for extracorporeal shock wave lithotripsy (ESWL). MATERIALS AND METHODS: This clinical study included 246 patients who underwent removal of urinary stones and an analysis of stone components between November 2009 and August 2013. All patients received preoperative DECT using two energy values (80 kVp and 140 kVp). Hounsfield units (HU) were measured and matched to the stone component. RESULTS: Significant differences in HU values were observed between uric acid and nonuric acid stones at the 80 and 140 kVp energy values (p<0.001). All uric acid stones were red on color-coded DECT images, whereas 96.3% of the nonuric acid stones were blue. Patients with calcium oxalate stones were divided into two groups according to the amount of monohydrate (calcium oxalate monohydrate group: monohydrate> or =90%, calcium oxalate dihydrate group: monohydrate<90%). Significant differences in HU values were detected between the two groups at both energy values (p<0.001). CONCLUSIONS: DECT improved the characterization of urinary stone components and was a useful method for identifying uric acid and calcium oxalate monohydrate stones, which are unsuitable for ESWL.
Adult ; Aged ; Calcium Oxalate/analysis ; Female ; Humans ; Kidney Calculi/*chemistry/*radiography/therapy ; *Lithotripsy ; Male ; Middle Aged ; Patient Selection ; Radiography, Dual-Energy Scanned Projection ; Tomography, X-Ray Computed/*methods ; Ureteral Calculi/*chemistry/*radiography/therapy ; Uric Acid/analysis