Urinary acidification in renal stone patients from northeastern Thailand.

Hypokalemia, hypokaliuria and hypocitraturia are common findings in patients with renal stone disease in Northeastern Thailand. However, hyperchloremic metabolic acidosis seldom is seen. Therefore, we studied renal acidification in 29 renal stone disease patients who were living in rural Northeast Thailand. Baseline blood and average 24-hour urine biochemical parameters were measured. Hypokalemia, hypokaliuria and hypocitraturia were found in 10%, 83% and 93% of the patients, respectively. By multiple regression, urinary citrate excretion correlated positively with serum potassium and urinary potassium excretion, and negatively with urinary ammonium (r = 0.640, p = 0.005). An abnormal response to acid loading was found in only 1 patient. Thus, hypokaliuria and hypocitraturia in our renal stone disease subjects were infrequently due to distal renal tubular acidosis. Perhaps potassium depletion might be a contributing factor in these metabolic abnormalities.     

1168例泌尿系结石患者结石成分分析及其饮食预防指导

目的:研究不同性别以及不同年龄段泌尿系结石患者结石成分组成特点,并探讨针对性饮食预防指导的措施及其效果。方法:回顾分析我院2011年1月~2012年5月收集的尿石症患者结石标本共1 168例,进行红外光谱结石成分分析,并针对不同的结石成分给予不同的饮食预防指导,911例执行饮食预防指导为预防组,257例未遵循饮食预防指导为对照组,随访24个月,并将不同结石成分类型及随访时段进行对比分析。结果:1 168份结石标本中,发生率最高的结石种类为草酸钙与碳酸磷灰石的混合结石,中年(41~60岁)为结石高发年龄段,占整个结石患者一半以上。随访患者中,预防组结石复发率约7.2%,对照组结石复发率为27.6%,饮食预防时间与结石复发率呈现负相关,差异有统计学意义。结论:草酸钙结石与碳酸磷灰石的混合结石发生率最高。男性发病率略高于女性。结石发病率在不同年龄段不同,其中中年发病率最高。针对性给予饮食预防指导可明显降低结石复发的风险。     

正常人和尿路结石病人的尿液GAGs分析

分析４０例尿路结石病人和１６名正常人的２４小时尿液ＧＡＧｓ水平。结果表明：结石患者２４小时尿ＧＡＧｓ总量和浓度分别为２７．９３±１０．９２ｍｇ和１９．００±７．５μｇ／ｍｌ，较正常人３４．３７±７．９０ｍｇ和２３．３０±６．４μｇ／ｍｌ为低，两组具有显著性差异（Ｐ＜０．０５）。对尿ＧＡＧｓ抑制尿路结石形成的机理及其应用前景进行讨论。     

三聚氰胺与泌尿系结石

三聚氰胺是一种化工原料,饲料中添加三聚氰胺可对动物的泌尿系统产生明显损害,可导致尿路结石和肾功能衰竭。近来发生在我国的问题奶粉事件也证实三聚氰胺对人类泌尿系统有损害作用。但三聚氰胺致泌尿系结石形成的机理尚未明了。本文就三聚氰胺的代谢动力学及其对动物和人类泌尿系的毒性损害,尤其是尿路结石形成的可能机理进行综述。     

Urinary stone disease in diabetes mellitus

OBJECTIVE: Diabetes mellitus (DM) and urinary stone disease (USD) are common diseases in the community. The prevalence of USD has not previously been studied in DM patients. MATERIAL AND METHODS: We evaluated 286 diabetics and 111 age-matched controls by means of direct urinary system X-ray, ultrasonography and/or intravenous pyelography. We also examined the history, risk factors and clinical aspects of USD in DM patients. RESULTS: The prevalence of USD (21% vs 8%; p < 0.05) and the rate of recurrence (2.1 +/- 2.2 vs 1.3 +/- 0.5 stones/case; p < 0.05) were higher in the diabetics compared to the controls. Family history and male gender were significant risk factors for the development of USD in the DM patients. Increased daily total fluid consumption was not preventive for USD in the DM patients, and the type of fluid consumed did not have an impact on the risk of USD. Alcohol consumption was a significant risk factor for the development USD in the DM patients (odds ratio 3.68; 95% confidence interval 1.29-10.45; p < 0.05). Crystaluria (10% vs 1%; p < 0.05) and positive urine culture (8% vs 1%; p < 0.05) were also more prominent in the diabetics compared to the controls. CONCLUSIONS: The results of this study suggest that DM is a risk factor for the development USD.     

Urinary tract stone disease in modern Japan. Stone incidence, composition and possible causes in Osaka district

2,969 stones, obtained from affiliated hospitals as well as the Osaka University Urologic Clinic were analyzed by infrared spectrophotometry. 2,724 of the 2,969 stones were obvious upper urinary tract stones, and the composition of these 2,724 stones is reported. The incidence and possible cause of stones in 750 patients with upper urinary tract calculi, managed in Osaka University Urologic Clinic, are discussed, as well as the recent figures on urinary tract stone disease in Osaka district. These figures are representative of stone disease in Japan.     

Urinary tract stone disease in the United States veteran population. II. Geographical analysis of variations in composition

The geographical distribution of crystalline components observed in urinary tract stones in the continental United States has been studied in the United States veteran population. Since the veteran population is at risk for urolithiasis the National Veterans Administration Crystal Identification Center was established in 1983 for the characterization of all crystal-containing veteran patient samples using high resolution x-ray powder diffraction. The geographical distribution of whewellite, weddelite, apatite, brushite, struvite, uric acid and uric acid dihydrate is presented. The percentage occurrence of the crystalline components, percentage occurrence of admixed stones and geographical distribution of the number of components in admixed stones also are presented. The data highlight that although the southeastern United States has the highest patient discharge rate for stones, this high discharge rate appears to be correlated specifically with a high discharge rate for calcium oxalate stones and not with a high discharge rate for any of the other common stone components.     

Urinary glycosaminoglycan composition in chronic glomerulonephritis

BACKGROUND: Glycosaminoglycans (GAG) play an important role in regulating glomerular permeability, and a reduction in their plasmatic concentration or urinary loss has been implicated in the pathogenesis of diseases associated with increased albumin permeability. The purpose of this study was to evaluate GAG excretion in renal pathology by analyzing the composition of urinary GAG in antibody mediated glomerular injury, such as mesangial glomerulonephritis (IgAGN) and primitive membranous glomerulonephritis (MGN), to verify the effects of glomerular capillary wall lesion with and without mesangial cell injury. METHODS: Urinary GAG excretion was analyzed in 20 patients with IgAGN, 18 patients with MGN, and in 18 healthy subjects (controls). GAG were isolated from 24-hr urine using ion-exchange chromatography on DEAE-Sephacel, and the results are expressed as mg hexuronate/g creatinine (Cr). GAG composition was determined by cellulose acetate electrophoresis and expressed as relative percentages by densitometric scanning of Alcian Blue stained strips. RESULTS: We found total GAG levels significantly higher in the urine of patients with MGN in comparison with controls and patients with IgAGN. The electrophoretic pattern analysis demonstrated low sulfated chondroitin sulfate proteoglycan (LSC-PG) in all patients compared to 44% in controls (8/18), but also low sulfated chondroitin sulfate (LSC) in 18.4% of patients (7/38) and slow migrating LSC (SM-LSC) in 8% of patients (3/38), only in the MGN group. Moreover, in patients with MGN, the LSC-PG relative content was significantly higher when compared to that observed in controls. Finally, in IgAGN and MGN patients, a significant reduction in chondroitin sulfate (CS) relative content was observed. CONCLUSIONS: It seems likely that an increase in total GAG levels takes place when a reduction in renal function occurs, but the alteration of CS and herapan sulfate (HS) relative contents, and the presence of LSC-PG and free LSC also in the urine of IgAGN patients, allows us to suggest that the GAG distribution pattern becomes abnormal before an increase in total urine GAG excretion. In addition, the quali-quantitative determination of urinary GAG and GAGprotein complex could constitute an additional non-invasive marker to appraise the metabolism of renal connective tissue in some renal diseases.     

Urinary material affecting calcium oxalate monohydrate stone formation

We previously reported that the low molecular and uronic acid-rich fractions in the urine from calcium oxalate stone formers promoted aggregation of calcium oxalate monohydrate seed crystals. In this study, we have demonstrated that lyophilized material of the fractions contains hyaluronic acid as a sole glycosaminoglycans, as well as acidic amino acid-rich proteins and urinary pigment which is supposed to combine with protein. It is known that hyaluronic acid is present in stone matrix, that calcium containing stones contain proteins rich in acidic amino acids, and that the external color of calcium oxalate monohydrate calculi is usually brownish. These facts correspond with our present results. Therefore, it is suggested that the urinary material promotes the calcium oxalate crystal aggregation, sticks the crystals together and is incorporated into the stone.     

Urinary stone disease in Turkey: an updated epidemiological study

In a nationwide survey conducted in 14 provinces on 1,500 individuals, an overall prevalence of 14.8% and an incidence of 2.2% for the year 1989 are found for urinary stone disease in Turkey. The male:female ratio was 1.5:1. The prevalence showed a geographical distribution with higher figures in southern and south-eastern parts of the country. Low socioeconomic and educational status were associated with a higher prevalence rate, while there was no significant difference between people living in rural areas or in cities. Similarly, occupation had no significant impact on the incidence of urinary stone disease. Urolithiasis is a severe problem in Turkey and more detailed epidemiological studies are needed to enlighten the pathogenetic factors of stone formation and its geographical variations.     

Urinary stone formation in children with prenatally diagnosed uropathies.

Among a series of 312 patients with prenatally diagnosed uropathies, 4 male children developed urinary calculi at ages varying from 2 to 5 years. All had upper urinary tract dilatation not associated with vesicoureteric reflux or with renographically defined obstruction; 3 followed Proteus urinary infections. Strategies for prevention are discussed.     

The relation between urinary tract infections and stone composition in renal stone formers

During a seven-year period (1975-1981) a total of 1325 patients hospitalized for stone disease were studied as to the occurrence of positive urine cultures. Urinary stones from 535 surgically treated patients were analyzed with infrared spectrophotometry and the relationships between stone composition, level of surgery and bacteriological strains were studied. Positive urinary cultures were found in 34% of the surgically treated patients and in 21% of those not operated upon. Among the surgically treated patients with urinary tract infection (UTI) E. coli was the most frequent microorganism (35%), followed by Proteus (28%). Patients with Proteus infection had the highest frequency of UTI episodes, most of which occurred before hospitalization. There was a higher frequency of magnesium ammonium phosphate (MAP) calculi among patients with Proteus infection than among those with non-Proteus infection, in whom no difference in stone composition was found. Patients infected with E. coli had more phosphate-containing stones (CaP+MAP) than non-infected patients. The highest frequency of oxalate calculi (CaOx+CaOx/CaP) was found among patients without infection. No E. coli infections were seen in male patients with CaP and MAP calculi. MAP stones were most often found in the kidney and oxalate stones in the ureter.