Demonstration of blood calcium-related parathyroid function in the diurnal variation of blood and urine calcium and phosphorus in healthy individuals

The circadian changes in blood and urine minerals and parathyroid function assessed by nephrogenous cyclic AMP (NcAMP) and a highly sensitive midregion specific parathyroid hormone (PTH) radioimmunoassay (RIA) were investigated for 26 hours in ten healthy 23 to 53-year-old males (group 1) with normal food intakes. Also, we studied another six male and four female adults between 600 and 1200 h as fasting controls (group 2). The blood calcium (Ca) levels were the highest at 630 h in both groups and decreased thereafter, and the diurnal variation of NcAMP reflected that of serum Ca, showing a low value in the morning. There were significant negative correlations between total Ca and NcAMP in both groups 1 and 2 (r=−0.323, n=130, p<0.01; r=−0.525, n=60, p<0.01), suggesting that the blood Ca level is the major determinant of parathyroid function and that NcAMP is a good indicator of blood Ca related PTH secretion in healthy individuals. This last relationship was not seen between Ca and midregion PTH levels presumably owing to slow clearance of PTH fragments from the circulation. However, midregion PTH perhaps because of its long half life, not NcAMP, shows a significant inverse relation to urinary Ca excretion (mg/dIGF) in the diurnal variation in healthy individuals (r=−0.560, n=130, p<0.01). The circadian pattern (s) of serum phosphate (P) consisted of a minium level at 900–1100 h followed by two peaks, at 1400–1600 h and 2200–2400 h. Thus, this study conducted in healthy individuals under physiologic condition clearly demonstrated that the NcAMP level reflects blood Ca related PTH secretion and that urinary Ca excretion seems to be determined by the sum of PTH secretion.     

瘦猪肉餐对草酸钙结石患者尿生化的影响

目的研究瘦猪肉餐对一水草酸钙（calciumoxalate monohydrate,COM）与二水草酸钙（calciumoxalate dehydrate,COD）结石患者尿生化的影响,探讨草酸钙结石形成的机制。方法正常人、COM与COD结石患者各6例,共18例同予以煮瘦猪肉350g食用,收集实验日晨5-7时2h尿为样本,餐后各留3次2h尿标本,测定尿pH值和尿晶体成分浓度;采用SPSS软件对检测结果进行方差分析。结果三组受试者瘦猪肉餐后尿钙、尿酸和尿草酸排泄逐渐增加,而尿量、尿pH值和尿枸橼酸降低;瘦肉餐前后比较,COM与COD结石患者尿pH值、尿枸橼酸、尿钙和尿草酸有显著性差异（P〈0.05）,尿酸排泄有极显著性差异（P〈0.01）;对照组,尿钙、尿酸排泄均有显著性差异（P〈0.05,P〈0.01）。结论大量饮食猪瘦肉可导致尿pH值和尿晶体成分变化,可能是尿结石形成的重要原因之一。     

A study of the etiology of idiopathic calcium urolithiasis in children: hypocitruria is the most important risk factor

PURPOSE: To determine the association of metabolic risk factors with pediatric calcium urolithiasis we compared metabolic evaluation data on children with idiopathic calcium stones and those on healthy children. MATERIALS AND METHODS: Metabolic evaluation was done in 78 calcium stone formers 1 to 15 years old (mean age 7.2) who were free of urinary tract infection, anatomical abnormalities, and metabolic, endocrinological and intestinal disorders, and in 24 healthy children. Evaluation included serum biochemistry, and measurement of daily excretion of urinary calcium, oxalate, urate, phosphorus, citrate and magnesium. RESULTS: Demographic characteristics, serum parameters, and daily excretion of calcium, urate, phosphorus and magnesium did not differ statistically in the 2 groups. However, urinary oxalate was significantly higher and urinary citrate was significantly lower in stone formers than in controls (p = 0.002 and 0.028, respectively). Hypocitruria and hyperoxaluria were 4.3 and 3-fold more common in stone formers than in controls, respectively. Multivariate analysis using logistic regression showed that hypocitruria was the only significant risk factor for idiopathic calcium stones (p = 0.008). CONCLUSIONS: Hypocitruria was the most important risk factor in our patients. Hyperoxaluria was also common and accompanied hypocitruria in many stone formers. In contrast to many previous reports, we failed to show that hypercalciuria is an important metabolic defect for idiopathic calcium stones, possibly because our study evaluated a different population.     

Proteomic analysis of a rare urinary stone composed of calcium carbonate and calcium oxalate dihydrate: A case report

The objective of the present study was to investigate the matrix protein of a rare urinary stone that contained calcium carbonate. A urinary stone was extracted from a 34‐year‐old male patient with metabolic alkalosis. After X‐ray diffractometry and infrared analysis of the stone, proteomic analysis was carried out. The resulting mass spectra were evaluated with protein search software, and matrix proteins were identified. X‐ray diffraction and infrared analysis confirmed that the stone contained calcium carbonate and calcium oxalate dihydrate. Of the identified 53 proteins, 24 have not been previously reported from calcium oxalate‐ or calcium phosphate‐containing stones. The protease inhibitors and several proteins related to cell adhesion or the cytoskeleton were identified for the first time. We analyzed in detail a rare urinary stone composed of calcium carbonate and calcium oxalate dihydrate. Considering the formation of a calcium carbonate stone, the new identified proteins should play an important role on the urolithiasis process in alkaline condition.     

泌尿系结石成分450例分析

目的分析泌尿系结石患者的发病年龄及性别特点,探讨结石部位与患者年龄及性别的关系,根据结石不同成分采用不同预防措施。方法应用化学分析法对450例尿路结石做成分分析,结合临床资料,对尿路结石患者发病年龄、性别、结石部位及结石成分做对比分析。姑杲男性患者321例,高发年龄21～60岁;女性129例,高发年龄41～60岁;男性发病率是女性的2．49倍。发病部位肾脏结石319例（70．8％）,输尿管结石115例（25．6％）,膀胱结石16例（3．6％）;单一成分结石275例（61％）,其中单纯草酸钙结石260例（57．7％）,两种及以上混合成分结石175例（39．0％）。结论尿路结石的发病率及发病年龄存在着明显的性别差异;尿路结石发病部位主要为上尿路结石;单一成分结石以草酸钙为主,约40％的尿路结石为两种及以上混合成分结石。     

尿钙水平对草酸钙结石患者尿液MCP-1和MDA生成的影响

目的：探讨尿钙水平在结石形成过程中的作用。方法：选择草酸钙结石住院患者110例,按尿钙水平分为两组,24小时尿钙≥240mg／d的35例纳入高尿钙结石组,24小时尿钙％240mg／d的75例纳入低尿钙结石组;同时随机挑选30例无泌尿系结石的健康者作对照组。收集三组尿液,分别运用ELLISA和TBA法检测尿液中细胞因子MCP—1、TGF—β和脂质过氧化产物丙二醛（MDA）的含量。结果：MCPl在高尿钙组、低钙尿组和健康对照组问的含量分别为36．7（23．71,50．22）pg／ml、29．22（20．40,40．29）pg／ml、26．98（13．59,38．60）pg／ml;与其他两组比较,高尿钙组尿液中MCP1生成增多（P〈0．05）。TGF-β在三组间含量无差别（P〉0．05）。MDA在高尿钙组、低钙尿组和健康对照组问的含量分别为2．02（1．05,2．95）nmol／ml、1．70（1．00,2．18）nmol／ml、1.19（0．73,1．41）nmol／ml;与健康对照组比较．高尿钙结石组和低尿钙结石组尿中MDA生成增加（P〈0．05）;高尿钙结石组和低尿钙结石组尿巾MDA则无明显差异（P〉0．05）。相关性分析,尿钙水平与尿MCP—1水平存在iESH关关系,r=0．226,P〈0．05;尿钙水平与MDA水平无明显相天关系（P〉0．05）。结论：高尿钙可促进草酸钙结石患者尿液MCP-1生成增多,TGF-β的生成无明显变化。草酸钙结石患者尿液MDA水平升高,提示肾脏氧化应激水平增加,但高尿钙并未影响患者尿MDA的生成水平,提示高尿钙在草酸钙结石患者肾脏氧化应激损伤中不越丰耍的作用．     

川东北地区泌尿系结石构成及其相关因素分析

目的分析川东北地区泌尿系结石的发病情况、成分以及分布特征,为其治疗及预防提供参考依据。方法回顾性分析2017年4月至2019年4月南充市中心医院收治的1564例泌尿系结石患者的结石标本,通过红外光谱分析系统对结石成分进行分析,并将患者的地域、性别、年龄、结石部位等数据进行分组,采用Excel建立数据库,进行统计学分析。结果1564例结石患者的地域分布有差异:以嘉陵区、顺庆区为多,占患者总数的17.8%和20.2%;周边地区以广安地区为多,占患者总数的9.8%。男性多于女性,二者的比例为1.42∶1。结石发病年龄分布较广:以40~59岁龄段所占构成比最高,约为53.00%。40~59岁患者主要以输尿管结石为主(52.0%,P<0.01),其次为肾结石(41.6%,P<0.01);≥60岁患者主要以肾结石为主(48.6%,P<0.01),其次是输尿管结石(40.5%)及膀胱结石(9.0%),<20岁及20~39岁年龄段结石检出率无统计学差异。结石成分:以一水草酸钙+二水草酸钙最多(29.8%,P<0.01),其次为一水草酸钙+二水草酸钙+碳酸磷灰石(20.4%,P<0.01)、无水尿酸(11.8%,P<0.01),不同年龄段及不同地区主要结石成分均有差异。结论川东北地区作为泌尿系统结石的高发地区,发病情况存在一定的年龄及地域差异,根据结石分布特点及成分分析结果,为泌尿系结石的病因诊断、治疗及预防复发提供重要的理论依据。     

Role of urinary supersaturation in the evaluation of children with urolithiasis

Timed urine collections are a standard part of the evaluation for predisposition to stone formation in children with urolithiasis. Supersaturation is defined as the ratio of the concentration of dissolved salt to its solubility in urine. The purpose of the present study was to determine if adding supersaturation to the standard timed urine collection increased the ability to detect a metabolic predisposition to stone formation. Thirty-two children with urolithiasis had 24-hour urine measurements of calcium, oxalate, citrate, uric acid, and cystine (the traditional evaluation), as well as supersaturation for calcium oxalate, calcium phosphate, and uric acid, on the same urine sample. Nine (28%) of the 32 were hypercalciuric, 2 (6%) hyperoxaluric, and 4 (12%) hypocitraturic. In total, 14 (44%) had a metabolic predisposition that was detected by the traditional evaluation. Supersaturation was elevated in 18 (56%), including nine who did not have metabolic predisposition detected by traditional evaluation. Urine volume was low in 17 (53%) of 32 children, including eight of nine children with abnormal supersaturation but normal traditional evaluation. Only one child with normal traditional evaluation and normal urine volume had elevated supersaturation. These results show that the benefit of adding supersaturation to the traditional evaluation was largely negated by consideration of urine volume.     

Milk of calcium renal stone: A case report

A case of milk of calcium renal stone was reported. It is an unusual condition in which there is suspension of calcium salt within a pyelogenic cyst. The diagnosis is difficult because of its rarity. Reviewing literature, plain abdominal X-ray in different positions were emphasized. We found that fluoroscopy with spot films in different positions is worth-while. It has to be differentiated from gallstone and also from usual renal stone. Conservative treatment is advised if there is no suggestive malignancy.     

Changes in the incidence of lower urinary tract stones in Japan from 1965 to 1995

BACKGROUND: The changes over time of the annual incidence of lower urinary tract stones in Japan from 1965 to 1995 were analyzed. METHODS: Data on lower urinary tract calculi were abstracted from the past three nationwide surveys of urolithiasis, which covered nearly all major hospitals and urologists in Japan and enumerated all outpatient visits diagnosed as urolithiasis in the years 1965, 1975, 1985 and 1995. Chronological changes in the sex- and age-related annual incidences of lower urinary tract stones and stone composition were estimated. RESULTS: Lower urinary tract stones were predominant in men 60 years of age or older. Between 1965 and 1995, the annual incidence has significantly decreased in men > or = 60 years of age from 37.2 to 27.0 per 100000 and significantly increased in women > or = 60 years of age from 2.4 to 4.8 per 100000. In men, an increased proportion of uric acid and calcium stones as well as a decreased frequency of infection stones is a phenomenon common to upper urinary tract stones. However, infection and calcium stones have been two major stone types in women. CONCLUSIONS: In contrast to upper urinary tract calculi, the incidence of lower urinary tract stones has decreased over the last 30 years in men > or = 60 years of age predisposed to this disease.     

Factors associated with low and high voiding frequency in children with diurnal urinary incontinence

Study Type – Prognosis (cohort)
Level of Evidence 2a

OBJECTIVE

To investigate, in a population‐based study, the association of urinary voiding frequency and daytime wetting or diurnal urinary incontinence (UI) in children aged 6.5 years, to test the hypothesis that children with high or low voiding frequency have increased somatic and psychological risks.

SUBJECTS AND METHODS

Participants were a cohort of >8000 children enrolled in the population‐based Avon Longitudinal Study of Parents and Children, a prospective longitudinal study of an original birth cohort of nearly 14 000 children. Parents completed postal questionnaires asking about diurnal UI, voiding frequency and associated somatic and behavioural signs and symptoms.

RESULTS

In all, 10.4% of children had diurnal UI. Children with diurnal UI had significantly more gastrointestinal, urinary and psychological symptoms than the controls. Of the children with diurnal UI, 35.7% had a voiding frequency of <5 voids/day, 61.5% 5–9 voids/day and 2.8%≥ 10 voids/day. High voiding frequency was more common in boys, children with frequent diurnal UI and those with combined diurnal and night‐time UI, and also in children with nocturia, urgency, hyperactivity and conduct problems. Children with a low voiding frequency needed to be reminded to go to the toilet more often. Fecal incontinence, constipation, stomach ‘aches’, ‘choosy’ eating and urinary tract infections were not associated with voiding frequency.

CONCLUSIONS

Voiding frequency is an important symptom in children with diurnal UI. The children with high voiding frequencies are especially at risk for associated somatic and behavioural problems.     

Therapeutic action of citrate in urolithiasis explained by chemical speciation: increase in pH is the determinant factor.

BACKGROUND: The therapeutic action of citrate in the management of calcium oxalate urolithiasis has been attributed to the depletion of free calcium ions by complexation of the latter by citrate itself. However, little attention has been given to the nature of such complexes and the chemical conditions which control their formation because it is very difficult to measure them in solution. We therefore modelled the theoretical formation of these complexes in urine following administration of a citrate-containing preparation, using a powerful speciation program, JESS (Joint Expert Speciation System), which has been widely used to model metal-ligand equilibria in biological systems but which has hitherto not been applied in urolithiasis research. This program has an extensive database of thermodynamic constants and is able to calculate mixed ligand speciation. METHODS: Urine data obtained before and after citrate administration in four groups of subjects (male and female normals and stone formers) were used as input for JESS to calculate the speciation of calcium, citrate and oxalate. The program was also used to examine the effects of varying different urinary components on the nature and concentration of the various species. RESULTS: The speciation predicted the formation of a key calcium-citrate-phosphate species (previously unreported in urolithiasis research), which accounts for a significant percentage of the complexation of the free calcium. Moreover, the formation of this complex was found to be dependent on an increase in urinary pH rather than on an increase in urinary citrate concentration per se. CONCLUSION: The therapeutic action of citrate in the management of calcium oxalate urolithiasis is due to the formation of a pH dependent calcium-citrate-phosphate complex which reduces the concentration of the free calcium ion species, thereby reducing the risk of stone formation.     

Inhibitions of urinary oxidative stress and renal calcium level by an extract of Quercus salicina Blume/Quercus stenophylla Makino in a rat calcium oxalate urolithiasis model

Objectives:   To clarify the mechanism of Urocalun, an extract of Quercus salicina Blume /Quercus stenophylla Makino (QS), in the treatment of urolithiasis.
Methods:   Rat calcium oxalate urolithiasis was induced by oral administration of ethylene glycol and the vitamin D₃ analog alfa-calcidol for 14 days. QS extract was repeatedly given to rats. After the last administration, biochemistries in urine and plasma, renal calcium, and urinary malondialdehyde (an oxidative stress marker) were measured.
Results:   Ethylene glycol and alfa-calcidol treatment increased urinary malondialdehyde and renal calcium levels. This increase was significantly suppressed by the administration of QS extract, suggesting that the inhibition of renal calcium accumulation by QS extract is due to its antioxidative activity.
Conclusions:   These findings suggest that the antioxidative activity of QS extract plays a role in the prevention of stone formation and recurrence in urolithiasis.     

Effect of ethyl icosapentate on urinary calcium and oxalate excretion

BACKGROUND: The effect of ethyl icosapentate (EPA-E) on urinary calcium and oxalic acid excretion was examined to evaluate whether EPA-E is useful in the prevention of calcium-containing urinary stones. METHODS: For 6 months, urine was measured daily from 40 calcium-containing urinary stone producers at an outpatient clinic, before and after the administration of 1800 mg/day EPA-E. The urine was measured for volume, urea nitrogen, creatinine, calcium, magnesium, phosphorus, uric acid, oxalic acid and citric acid. Serum total cholesterol and triglyceride were also measured. RESULTS: Urinary calcium excretion was not reduced in any of the patients or particular hypercalciuric groups, nor did the level of calcium change. However, nine of the 25 hypercalciuric patients experienced a significant urinary calcium reduction to the normal calciuric level (a reduction of approximately 44%). It is not known why these particular patients experienced a reduction. Urinary oxalic acid did not change, whether hypercalciuria was present or not. CONCLUSIONS: These findings suggest that EPA-E is not particularly effective in reducing urinary calcium excretion in the hypercalciuric patients, but it needs future investigation because some patients experienced significant urinary calcium reduction.