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Assessment of kidney stone and prevalence of its chemical compositions
Abstract
Kidney stone analysis is the test done on the stone which cause problems when they block the flow of urine through or out of the kidneys. The stones cause severe pain and are also associated with morbidity and renal damage. There is also no clear understanding on the relative metabolic composition of renal calculi. Hence, the study is aimed to find out the chemical composition of it which can guide treatment and give information that may prevent more stones from forming. The study was carried out on the stones that had been sent to the department of Biochemistry (n = 99; M = 61; F = 38; Mean age: 33.6 +/- 14.4 years) Approximately 98.9% of stones were composed of oxalate, 95.9% of Calcium, 85.8% of phosphate, 62.6% of Urate, 46.4% of Ammonium and very few percentages of Carbonate.
... 11,12 The mean age of the patients with renal colic was 33.9 years in this study and this finding was almost similar with other studies. [13][14][15] Some studies found that patients presenting with renal colic were younger. 16,17 More than half of the patients who developed renal colic were male. ...
... Several studies reported that renal stones are more common in males than in females. 11,[13][14][15][17][18][19][20][21] In contradictory to this finding, it was observed that there was a dramatic increase from 1997 to 2002 of the adjusted rate of stone disease in females in a representative sample of United States population. The increasing incidence might be due to lifestyle-associated risk factors, such as obesity. ...
... Kidney stone analysis is the test done on the stone which cause problems when they block the flow of urine through or out of the kidneys. The stones cause severe pain and are also associated with morbidity and renal damage 4 . Kidney stones are a risk factor for chronic kidney disease and progression to end-stage renal disease 5 . ...
... Therefore, all meat breaks down into uric acid. The plant sources of uric acid are seeds such as beans, peas, and lentils 4,5 . ...
This study was aimed to identify of chemical composition of kidney stones of patient in Sana’a , Yemen because the lack of research done in this field . The study was integrated within the clinical practice. Patients mothers or child's guardian received a simple explanation for the aim of the study an ethical issue. 581 samples of chemical compositions were collected and analyzed in the National Center for Public Health Laboratories Sana'a , Yemen according to qualitative method . The results showed that 54.6 % of the calcium oxalate, 6.3 % of the uric acid , 0.7 % of the calcium phosphate, 29.6 % of the calcium oxalate and uric acid , 6.7 of the calcium oxalate and calcium phosphate , 1 % calcium oxalate and calcium carbonate , 0.5 % of the calcium oxalate , calcium phosphate and uric acid , 0.5 % of the calcium oxalate , calcium carbonate and uric acid , and 0.2 % calcium phosphate and uric acid . In conclusion , calcium oxalate was the most predominant chemical compositions in stones and it represents common urological problem in Sana’a , Yemen .
Keywords: Analysis , Kidney, Stones, Chemical , Composition, Yemen
... Life time prevalence of symptomatic nephrolithiasis is around 10% in men and 5% in women and about more than $2 billion spent each year for treatment purpose (Taylor and Curhan, 2008;Taylor et al., 2005). A number of different kinds of factors are involved in increasing the risk of kidney stone formation like; excess calcium, phosphate, oxalate and uric acid in the urine, inadequate hydration, lack of stone inhibitors in the urine, family history of stone (Curhan et al., 1997), daily urine volume, high, large body size (Curhan et al., 1998), some medications and ongoing urine infection (Sowers et al., 1998;Stamatelou et al., 2003;Pandeya et al., 2010;Leonetti et al., 1998). Dietary risk factors play a very vital role in stone formation. ...
... While this ratio decreased significantly with use of boiled water (15.84%) previous studies also indicated that un-boiled water is a major factor in the formation of kidney stones (Sowers et al., 1998;Pandeya et al., 2010). Hypertension is also a major factor for stone formation (Cappuccio et al., 1990). ...
Aim
The main objective of the study was to determine the urinary risk factors involved in kidney stone formation.
Method
In this study total number of 101 patients (64 male and 37 female) between the age group 2-70 years were selected. Personal characteristics like age, family history, clinical sign and symptoms, education, monthly income, living style, smoking or tobacco chewing habit, dietary intake and daily amount of drinking water were recorded.
Results
The study showed that the risk for developing kidney stone formation was high in median age group (16-25 years) both in male and female population. The most important factors associated with this were lack of drinking clean water, over weight and obesity as well as family history (37.5% and 27.02% in men and women respectively).
Conclusion
Our study has confirmed that lack of drinking sufficient amount of water, increasing weight and obesity and family history are some major factors contributing to the increased risk of kidney stone formation. Therefore it is very important to live a healthy life, drink clean water and control weight to prevent such diseases.
... The other noteworthy cause may be more complicated male urinary tract than female one. 22 Calcium Oxalate was the predominant stone in the study undertaken. Of the total 1176 kidney stones, 765 (65%) contained calcium oxalate. ...
Renal calculus is a hard mass. It is formed from the crystals that aggregate onthe inner surfaces of the kidney. Small crystals flow to the urinary tract and pass out of the bodyspontaneously along with urine without being noticed. Objectives: The purpose of the presentstudy is to find the type; age and gender related prevalence of the renal calculus disease inSouthern Punjab Pakistan. Study design: The study design is retrospective. Period: Two yearfrom June 2009 to June 2011. Materials and Methods: In this work, 1176 samples of renalcalculi from both male and female patients of the southern Punjab, Pakistan, were collected.Semiquantitative analysis of the renal calculi was carried out using Merckogonost Reagent Kit.Results: Highest prevalence of the renal calculus disease was in the age group 40-49 in malesand in the age group 30-39 in females. The disease was more common in males than females.Calcium oxalate was the predominant renal stone.
... In contrast, females produce copious amounts of citric acid because of estrogen, which is protective against renal stones. 13,14 The participants in this study were above 18 years of age. The prevalence of renal stones reported in this study was the highest in the age group 18-30 years, followed by 34-40 years (29.00%), ...
Saudi Arabia has extremely hot climate for most of the year; this is associated with the risk of developing nephrolithiasis. This retrospective research aimed to investigate the current prevalence, manifestation, mode of treatment, and risk factors of renal stones in Jeddah and Riyadh, Saudi Arabia. A cross-sectional study was conducted from November 2018 to June 2019 at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. This study included 1031 participants aged ≥18 years from Jeddah (n=652, 63.3%) and Riyadh (n=379, 36.8%). Data were expressed as mean ± standard deviation (minimum-maximum) or number (%). Comparisons between patients with and without renal stones were made using the Chi-square test and unpaired Student's t-test as appropriate. The odds ratio (OR) with a 95% confidence interval (95% CI) was determined for the risk factors of renal stones. The prevalence of renal stones was 16.9% among the participants. A significantly high risk for renal stones was associated with male sex (2.96; 95% CI: 2.08-4.20, P = 0.0001) and age group of 34-40 years (OR: 1.44; 95% CI: 1.005-2.103, P = 0.047). Hypertension was more common in patients with renal stones than those without renal stones (9.5% vs.4.6%, P = 0.013). The percentage of patients who took diuretics was significantly higher among those with renal stones than among those without renal stones (11.2% vs. 3.5%, P = 0.001). Of the 169 patients with renal stones, 58.0% had a positive family history of renal stones, and 23.7% had a history of urinary tract infections (UTIs). The symptoms of renal stones were pain (86.4%), hematuria (11.2%), fever (2.4%), and others (0.6%). Of all the patients, 43.8% took medication. For most patients, the stones passed spontaneously (67.5%), while 23.7% underwent lithotripsy, and 1.5% received stents. In this study, we found a higher prevalence of renal stones two major cities in Saudi Arabia in Jeddah and Riyadh, at 16.4%. Risk factors included male sex and age group of 34-40 years. A significant number of patients with renal stones have a family history of renal stones and a history of UTI. Loin pain and hematuria were the two major clinical presenting symptoms for renal stones. In the majority of patients, the renal stones passed spontaneously without the need for lithotripsy or surgery.
... Other studies demonstrated that the higher prevalence of nephrolithiasis may be due to the reason that males have a greater muscle mass compared to females. Consequently, metabolic waste is increased due to the daily breakdown of the tissue, and hence tend to form nephrolithiasis increased (13) . These results agree with some studies that revealed that sex as a risk factor for nephrolithiasis. ...
Background: Urolithiasis, is a global problem affecting almost all populations in the world and it is a multifactorial disease caused by environmental, hormonal, and genetic factors. Objective: the present study was conducted to investigate the association of CSF-1 and CD44 with the risk of kidney stone. Methods: A total of 45 patients with Kidney stones were included in the study who were admitted to the hospital from the period between March to August 2019, and other groups consist of 45 healthy individuals. A three ml of blood samples were collected for polymerase chain reaction amplification and detection of CSF-1 and CD44. Results: Overall, highly significant differences can be found in the distribution of the genotype and allele frequencies of CSF-1(rs2050462) between the nephrolithiasis patients and control subjects (P< 0.001). The effect of CD44 polymorphism on susceptibility to nephrolithiasis, were different in the frequency of allele and genotype (rs13347) between patients and healthy controls, with statistically highly-significant (p< 0.001). Conclusion: Polymorphisms in CSF-1 and CD44 affect the risk of nephrolithiasis.
... Thus the daily breakdown of tissue results in increased metabolic waste and a predisposition of stone formation. The other more significant cause may be due to of the male urinary tract being more complicated than female [9]. ...
Objective: To find out the chemical composition of urinary tract stones in patients attending our hospital. Methods: A cross sectional hospital based study was conducted among 140 patients from October 2011 to September 2014 in SSMC & MH. The study included all patients of either gender and all ages who were diagnosed to have urinary tract stones and were managed in our hospital. Chemical analysis of stones were performed on stones, fragments, gravel’s passed spontaneously, or retrieved from endourological intervention or after ESWL or open surgery. Results were reviewed and analyzed with the help of SPSS17. Result: Out of 140 patients about one third (31.4%) were female and two thirds were (68.6%) male. Most of the patients belong to age group 40-50 years. Mean age of the patients was 43.74 years with standard deviation of 10.28 years. 20% of the patients have recurrent stones. By the type of symptoms all of the patients had loin or back pain. One third of the patients had (36.7%) calcium oxalet stones, more than one fourth of respondents (27.1%) had mixed stones and 12.9% had magnesium, ammonium phosphate stones. Calcium containing stones were the most(60%). Conclusion: Calcium containing stones constitute the most common variety of urinary tract calculi in our local population. Bangladesh Journal of Urology, Vol. 18, No. 1, Jan 2015 p.8-11
... Also, male urinary tract is more complicated than female urinary tract. (20) Renal stones result when urine becomes very concentrated and substances in the urine crystallizes to form stones. Most of the stones that are recovered from patients had mixed heterogenous chemical composition ( Table 2). ...
Background: There are many reports regarding renal stone disease, which have documented that it is a complex disease process and widely distributed in developed as well as developing world with varied chemical constitution of these stones in relation to a varied risk factors. The present study was designed to qualitatively investigate the chemical constitution of the renal stones in the rural population of South Solapur, Maharashtra and also to study the dietary habits and water used for drinking purpose in renal stone patients. Method: The study was conducted on a total of 130 renal stone patients, comprising 90 males and 40 females, selected from Results: The analysis of chemical composition of renal stones showed that all the analysed stones were of different types. Carbonate was predominantly present (96.1%) which was followed by uric acid (94.6%), calcium (92.3%), phosphate (83.8%), oxalate (52.3%), ammonia (44.6%) and cystine (23.0%). The relative frequency of urolithiasis was more (67.6%) in patients who used ground water for drinking purpose as well as in those with a non-vegetarian diet (73.8%). Conclusion: The study concludes that simple qualitative chemical analysis helps us to evaluate chemical composition of renal stones and serves as a reliable diagnostic marker. Thus it can be useful in advising people for taking preventive measures.
... Therefore fourier transform infrared spectroscopy is considered as the most suitable technique for stone analysis (Basiri et al., 2012;Khaskheli et al., 2012). The information of chemical composition of layers of stones is essential for knowing their etiology and seems to be helpful in making some preventive measures against the disease (Pandeya et al., 2010). Up to date there is no reported work regarding study of layers of kidney stones for knowing their etiology have been carried out so far. ...
Present study is aimed to explore the rapid and reliable method of analyzing the composition of concentric layers of stones by fourier transform infrared spectroscopy with Kidney Stone Library Software (KSLS-13). Total of 69 kidney stones recovered from kidney stone patients (33 males and 36 females, mean age ranges of males and females were 10.1 to 37.3 & 15.2 to 54.4 respectively) were analyzed by fourier transform infrared spectroscopy. Composition of central, middle, peripheral layers of each kidney stone and whole stone were analyzed in the research laboratory of Institute of Biochemistry. Spectra of layers of kidney stones were collected and compared with kidney stone library software (KSLS-13). Among 69 kidney stones, 25 (36.2%) were pure stones (23.2% pure Calcium oxalate mono hydrate (COM), 10% pure carbonate apatite (CA), 3% pure magnesium ammonium phosphate (MAP)) and 44 (63.7%) mixed stones. Among 69 kidney stones, most prevalent were pure calcium oxalate stones (23.2%) and calcium oxalate mono hydrate stones mixed with carbonate apatite and ammonium hydrogen urate (AHU) (18.8%). The IR bands were compared with KSLS-13 as well as with standards. Calcium oxalate mono hydrate, carbonate apatite and uric acid were significantly increased in middle layer, but ammonium hydrogen urate and calcium oxalate dihydrate (COD) were increased in periphery. Whereas, reverse was true for magnesium ammonium phosphate in central layer. In conclusion, KSLS-13 by FTIR is found to be the most rapid and reliable method to study composition of concentric layers of kidney stones.
... This regional differences may be attributable to the environmental as well local dietary habits. 4 Ultrasound was found to have increased sensitivity and specificity in the diagnosis of ureterolithiasis. However, various studies have shown absence of initial hydroureteronephrosis can make diagnosis difficult or misleading as was noted in four patient in our study. ...
Introduction: Acute abdomen is the most common condition for patients presenting in the emergency. Ultrasound among other imaging modalities is the most common diagnostic tool employed in the diagnosis of such cases.Methods: A prospective study of consecutive patients presenting with acute abdomen fulfilling the inclusion and exclusion criteria were included in the study. Ultrasound was performed by single radiologist and findings were correlated to the clinical, pathological and surgical findings.Results: A total of 248 patients fulfilled all criteria and were included in the study. The age of patients ranged from 15-62 years with mean age of 41.3 years. There was female predominance with a male to female ratio of 1:1.8. Ultrasound accurately diagnosed 233 cases (93.9 %). Urolithiasis was the most common finding (45.16%) followed by acute appendicitis (19.35%).Conclusion: Ultrasound has pivotal role in the diagnosis and overall management of patient presenting with acute abdomen. Urolithiasis is the most common etiology for non- traumatic acute abdomen.
... Excessive consumption of meat protein also leads to marked increase in kidney stones, because meat causes over acidification of urine, which leads to increased excretion of oxalates, calcium and uric acid, whereas the excretion of citrate, provides protection and reduction in stone formation. [4] The aetiology of this disorder is multifactorial and is strongly related to dietary life-style habits or practices. [5] Adiantum capillus-veneris Linn. is an important drug widely used in patients of urolithiasis and is included as an important ingredient in many formulations used for litholytic activity. ...
Background: Adiantum capillus‑veneris Linn. is widely used in the management of urolithiasis in Unani system of medicine.
Aim: To evaluate the effect of the hydro alcoholic extract of A. capillus‑veneris Linn. on calcium oxalate crystallisation by in vitro
study. Materials and Methods: The study includes crystallization, nucleation and aggregation assay. Crystallization was induced by
addition of 50 µl of 0.1 M sodium oxalate in whole urine in the absence and the presence of extract at different concentrations (0.50 mg,
0.75 mg and 1 mg). The nucleation and aggregation rates were followed at 620 nm after mixing calcium chloride and sodium oxalate
solution and in a buffered solution containing calcium oxalate monohydrate crystals, respectively. The rate was evaluated by comparing
the slope of turbidity in the presence of extract with that of control using the spectrophotometer. Crystals in the urine were also
analysed by light microscopy. Results and Conclusion: Extract of the test drug inhibited the crystallization in solution; less and
smaller particles were observed in the presence of extract. These results were further confirmed in the nucleation assay, though the
rate of nucleation was not inhibited but number of crystals was found to be decreased. The test drug also inhibited crystal aggregation.
It can be concluded therefore, that the test drug possesses significant antilithiasic activity.
Key words: Calcium oxalate crystallization, in vitro, lithotriptic activity, unani medicine, urolithiasis
... The same patient may have more than one type of stone concurrently (e.g., calcium oxalate and uric acid). [4] In Saudi Arabia, it was found that the majority of the stones were composed of calcium (78%) followed by uric acid (19%) and phosphate (3%). Cystine stones were not reported in that paper. ...
Background: Nephrolithiasis is a common condition that has various classifications according to stone composition. Stone formation can affect renal function; it can be a strong risk factor for chronic kidney disease (CKD). The main objective of this study is to explore the association between creatinine clearance and different stone compositions. Methods: This is a retrospective cohort study conducted in a tertiary center in Jeddah, Saudi Arabia, between 2005 and 2014. Renal function was assessed by the estimating glomerular filtration rate (EGFR) by the Cockcroft-Gault equation. Stone composition was determined by urinary calculi analysis with infrared spectrometry. Results: Stones of 365 patients, with a mean age of 48.2 ± 13.6 years and a male to female ratio of 3.2:1, were analyzed. Stage 2 CKD has been documented. It involved oxalate, struvite, cystine, and uric acid stones. The worst EGFR was reported for stones containing uric acid. The EGFR was least affected with apatite stones followed by brushite stones. Conclusion: Stone disease can affect renal function. Different stone compositions show factor for renal impairment, and this should be considered in patient management. A special precaution should be considered for higher risk groups. Multidisciplinary patient care and immediate referral to a nephrologist are strongly advised.
... The same patient may have more than one type of stone concurrently (e.g., calcium oxalate and uric acid). [4] In Saudi Arabia, it was found that the majority of the stones were composed of calcium (78%) followed by uric acid (19%) and phosphate (3%). Cystine stones were not reported in that paper. ...
Background: Nephrolithiasis is a common condition that has various classifications according to stone composition. Stone formation can affect renal function; it can be a strong risk factor for chronic kidney disease (CKD). The main objective of this study is to explore the association between creatinine clearance and different stone compositions.
Methods: This is a retrospective cohort study conducted in a tertiary center in Jeddah, Saudi Arabia, between 2005 and 2014. Renal function was assessed by the estimating glomerular filtration rate (eGFR) by the Cockcroft-Gault equation. Stone composition was determined by urinary calculi analysis with infrared spectrometry.
Results: Stones of 365 patients, with a mean age of 48.2 ± 13.6 years and a male to female ratio of 3.2:1, were analyzed. Stage 2 CKD has been documented. It involved oxalate, struvite, cystine, and uric acid stones. The worst eGFR was reported for stones containing uric acid. The eGFR was least affected with apatite stones followed by brushite stones.
Conclusion: Stone disease can affect renal function. Different stone compositions show factor for renal impairment, and this should be considered in patient management. A special precaution should be considered for higher risk groups. Multidisciplinary patient care and immediate referral to a nephrologist are strongly advised.
... This cross-sectional study also provided important information on the pattern of urolithiasis in a developing country. In the present study, the gender distribution was comparable with previous international and local data and showed a male preponderance of urolithiasis (male:female ratio, 4.6:1) [14][15][16][17][18]. Most of the stones from this study were of the mixed variety with more COM and uric acid content (Table 3). ...
Purpose:
To compare the results of a chemical method of kidney stone analysis with the results of Fourier transform infrared (FT-IR) spectroscopy.
Materials and methods:
Kidney stones collected between June and October 2015 were simultaneously analyzed by chemical and FT-IR methods.
Results:
Kidney stones (n=449) were collected from patients from 1 to 81 years old. Most stones were from adults, with only 11.5% from children (aged 3-16 years) and 1.5% from children aged <2 years. The male to female ratio was 4.6. In adults, the calcium oxalate stone type, calcium oxalate monohydrate (COM, n=224), was the most common crystal, followed by uric acid and calcium oxalate dihydrate (COD, n=83). In children, the most frequently occurring type was predominantly COD (n=21), followed by COM (n=11), ammonium urate (n=10), carbonate apatite (n=6), uric acid (n=4), and cystine (n=1). Core composition in 22 stones showed ammonium urate (n=2), COM (n=2), and carbonate apatite (n=1) in five stones, while uric acid crystals were detected (n=13) by FT-IR. While chemical analysis identified 3 stones as uric acid and the rest as calcium oxalate only. Agreement between the two methods was moderate, with a kappa statistic of 0.57 (95% confidence interval, 0.5-0.64). Disagreement was noted in the analysis of 77 stones.
Conclusions:
FT-IR analysis of kidney stones can overcome many limitations associated with chemical analysis.
... The agents who can modify nucleation, crystallization, and aggregation, pH of the urine also play important role in stones formation. Some reports have described that vegetarians are at lower risk for stones formation in contrast to non-vegetarians 20 . A family history of kidney stones (increases risk by three times), insulin resistant states, a history of hypertension, primary hyperparathyroidism, a history of gout, chronic metabolic acidosis, and surgical menopause are all associated with increased risk of kidney stones. ...
There is an old and famous fact "the garden is the poor man's apothecary" and treatment of each and every disease is hidden i n nature. Medicinal plants are highly esteemed all over the world as a rich source of therapeutic agents for the prevention and treatment of various diseases. Since ages, herbs are being used for treating different ailments in different parts of world b y different communities. A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine. The problem of urinary stones or calculi is a very ancient one these stones are found in all parts of the urinary tract, the kidney, and the urinary bladder and may vary considerably in size. Urolithiasis is a complex process that occurs from series of several physicochemical event including super-saturation, nucleation, growth, aggregation and retention within the kidneys. Present article deals with reason, types of kidney stones, risk factors associated, diagnosis and treatment methods including many medicinal plants as herbal option for treatment of urinary stones.
... Several studies have been manipulated in many parts of the world by different surgeon, to look into the structure & biochemistry of renal stones. Current results confirmed other studies like that a pure calcium oxalate stone is common in Bahawalpur that is 65% & 33% in studies conducted by E.J. Westbury (5) (25), 99 kidney stones were analyzed, 70% were Calcium oxalate. Kidney stones have multifactorial causes in Nepal, but some predisposing conditions include environmental factors, like diet, play a momentous role in the elucidation of the tendency towards calculi formation. ...
The purpose of the study was to produce awareness and assess the frequency of calcium oxalate stone in adult males from Bahawalpur. It is a cross-sectional study. The current study was conducted in urology ward, Bahawal Victoria Hospital, and then analyzed in a chemical pathology laboratory, Quaid-e-Azam Medical College, Bahawalpur, Pakistan. A sample of 320 patients was selected. The data were collected through a questionnaire. The questions were translated into local language by the interviewer for better comprehension, and the answers were reverse translated into English, and filled in the respective columns. The study showed that out of 320 patients, calcium oxalate stones were in 65% of patients. Uric acid, pure calcium oxalate, and calcium phosphate stones were in 24% patients, magnesium ammonium phosphate (struvite) stones were in 5% patients, pure calcium phosphate stones were 4% patients & cysteine acid stones were in 2% patients. In adult males of Bahawalpur, calcium oxalate calculi are abundant in adult males, i.e., 65%. In adult males of Bahawalpur, Pure Calcium oxalate stones are more common. It is due to hot climate; peoples are vegetarians. The water of Bahawalpur contains high levels of minerals. Most people are not using purified water. They have not cared about diet which causes renal stones.
... The majority of stones were located in bladder (67:87%). Chemical compositions of stones in 99 Nepalian children were assessed [72]. Main components were oxalate (98.9%), calcium (95.9%), phosphate (85.8%), ...
This study was conducted to review urolithiasis in Asian children with a focus on urinary metabolic factors. A literature search of Pub Med and Google identified pertinent articles from 20 different Asian countries which were subsequently reviewed. A totally of 12.913 children (M/F ratio of 2.37/1) were enrolled in the studies. Hypercalciuria, hyperuricosuria, hyperoxaluria, hypocitraturia and decreased urinary magnesium excretion were reported in 652 of 4509 (14.45%), 276 of 3137 (8.8%), 1053 of 3973 (26.5%), 1940 of 2846 (68.2%), 32 of 240 (13.3%) of subjects, respectively. Cystinuria was noted in 112 of 4106 (2.7%) and mixed metabolic abnormalities were found in 175 of 724 (24.2%) patients. Association of urinary tract infection with stone disease was common in our series [2454 of 6430; (38.16) cases]. Urologic abnormalities were uncommon and recorded in only 447 of 9788 patients (4.5%). The etiology of stone formation was idiopathic in 731 of 2731 (26.8%) patients. Analysis of 3977 stones indicated that 983 (24.9%) were pure Ca stones, whereas 1579 (40%), 411 (10.4%), 38 (0.95%) and 288 (7.35%) were mixed Ca, uric acid or urate, cystine and struvite stones respectively. The study showed that hypocitraturia and hyperoxaluria are the most common metabolic abnormalities. Overall, calcium was the main component of stones with the except that bladder stones were composed of urate or uric acid alone or in combination with calcium. In addition, uric acid stones which are uncommon among American children were frequently reported in Asian children.
... Despite of differences in diet between both sexes may be a contributing factor to this fact. The other cause may be that the male urinary tract being more complicated than that of the female [31]. The average of body weight of patients (92.6 kg) was consistent with some recent investigations, which suggested that the obesity and overweight can increase the risk factors and contribute to kidney stones www. ...
Determination of the chemical constituents of kidney stones aids to establish the etiology of stones disease. The present study was carried out to investigate the composition of kidney stones to provide assistance for appropriate preventive treatment of the patient and to prevent a recurrence of stone formation in northern Jordan population. A total of 50 kidney stone samples were recovered from patients who were admitted to King Abdullah University Hospital (KAUH) and Princess Basma Teaching Hospital, Irbid, Northern Jordan, who were subjected to surgical operation 11 females and 39 males; age range 23 to 85 years during 2013-2014. Gender wise comparison revealed that majority of the stones (78.0%) analyzed were recovered from male patients. Whereas, stones recovered from females were only 22.0%. The composition of all samples was found by the chemical method using BIOLABO analysis kit. The 50 analyzed samples of kidney stones comprised 40.0% calcium oxalate and uric acid mixed stones, 22.0% calcium oxalate stones, 18.0% uric acid stones, 10.0% magnesium ammonium phosphate stones (struvite), 6.0% calcium oxalate-phosphate stones, and 4.0% cystine stones. The relationship between the chemical constituents of stones and both sex and age was established. There were some variations in frequencies of stones compositions according to age. In considering variation between genders, ammonium was higher among female patients whereas cystine stones formed only in males. In conclusion, Calcium oxalate and uric acid mixed stones were the most predominant type in stones of 50 patients.
... The other noteworthy cause may be more complicated male urinary tract than female one. 22 Calcium Oxalate was the predominant stone in the study undertaken. Of the total 1176 kidney stones, 765 (65%) contained calcium oxalate. ...
... Most of these stones probably contain calcium as the major cation and phosphate or oxalate as the major anion as is the norm in various studies. [12][13][14][15] Another point in favour of this logic is that Calcium stones are predominant in acidic urine while ammonium containing stones are more common in alkaline urine. ...
Background: This article aims to decipher chemical composition of renal stones and briefly outline laboratory tests and dietary habitual changes aimed at preventing stone recurrence. It is based on analysis of 95 renal stones received in a private lab in Kathmandu over a period of 1 year. Materials and Methods: Renal stones were analysed using simple qualitative biochemical tests.The stones were checked for presence of calcium, magnesium, ammonium, oxalate, phosphate, uric acid, cystine and carbonate. Results: Calcium was present in 97.8%, ammonium was present in 98.9%, phosphate was present in 25.2%, uric acid was present in 17.8%, magnesium was present in 10.5%, carbonate was present in 2.1% and cystine was not present in any of the stones. Most of the stones were composed of mixture of two or more than two of the above mentioned elements. Conclusion: Most stones are mixture of more than two cations and anions. Studies on larger test samples and if possible in correlation with routine examination of urine and urinary electrolyte excretion in a 24 hr urine sample would further aid in efforts aimed at preventing stone recurrence. DOI: http://dx.doi.org/10.3126/jpn.v4i7.10314 Journal of Pathology of Nepal (2014) Vol. 4, 560-564
... The majority of stones were located in bladder (67:87%). Chemical compositions of stones in 99 Nepalian children were assessed [72]. Main components were oxalate (98.9%), calcium (95.9%), phosphate (85.8%), ...
... The majority of stones were located in bladder (67:87%). Chemical compositions of stones in 99 Nepalian children were assessed [72]. Main components were oxalate (98.9%), calcium (95.9%), phosphate (85.8%), ...
This study was conducted to review urolithiasis in Asian children with a focus on urinary metabolic factors. A liter-ature search of Pub Med and Google identified pertinent articles from 20 different Asian countries which were subsequently reviewed. A totally of 12.913 children (M/F ratio of 2.37/1) were enrolled in the studies. Hypercalciuria, hyperuricosuria, hy-peroxaluria, hypocitraturia and decreased urinary magnesium excretion were reported in 652.3%) of subjects, respectively. Cystinuria was noted in 112 of 4106 (2.7%) and mixed metabolic abnormalities were found in 175 of 724 (24.2%) patients. Association of urinary tract infection with stone disease was common in our series [2454 of 6430; (38.16) cases]. Urologic abnormalities were uncommon and rec-orded in only 447 of 9788 patients (4.5%). The etiology of stone formation was idiopathic in 731 of 2731 (26.8%) patients. Analysis of 3977 stones indicated that 983 (24.9%) were pure Ca stones, whereas 1579 (40%), 411 (10.4%), 38 (0.95%) and 288 (7.35%) were mixed Ca, uric acid or urate, cystine and struvite stones respectively. The study showed that hypocitraturia and hyperoxaluria are the most common metabolic abnormalities. Overall, calcium was the main component of stones with the except that bladder stones were composed of urate or uric acid alone or in combination with calcium. In addition, uric acid stones which are uncommon among American children were frequently reported in Asian children.
... The majority of stones were located in bladder (67:87%). Chemical compositions of stones in 99 Nepalian children were as- sessed [72]. Main components were oxalate (98.9%), calcium (95.9%), phosphate (85.8%), ...
Abstract. This study was conducted to review urolithiasis in Asian children with a focus on urinary metabolic factors. A liter-ature search of Pub Med and Google identified pertinent articles from 20 different Asian countries which were subsequently reviewed. A totally of 12.913 children (M/F ratio of 2.37/1) were enrolled in the studies. Hypercalciuria, hyperuricosuria, hy-peroxaluria, hypocitraturia and decreased urinary magnesium excretion were reported in 652 of 4509 (14.45%), 276 of 3137 (8.8%), 1053 of 3973 (26.5%), 1940 of 2846 (68.2%), 32 of 240 (13.3%) of subjects, respectively. Cystinuria was noted in 112 of 4106 (2.7%) and mixed metabolic abnormalities were found in 175 of 724 (24.2%) patients. Association of urinary tract infection with stone disease was common in our series [2454 of 6430; (38.16) cases]. Urologic abnormalities were uncommon and rec-orded in only 447 of 9788 patients (4.5%). The etiology of stone formation was idiopathic in 731 of 2731 (26.8%) patients. Analysis of 3977 stones indicated that 983 (24.9%) were pure Ca stones, whereas 1579 (40%), 411 (10.4%), 38 (0.95%) and 288 (7.35%) were mixed Ca, uric acid or urate, cystine and struvite stones respectively. The study showed that hypocitraturia and hyperoxaluria are the most common metabolic abnormalities. Overall, calcium was the main component of stones with the except that bladder stones were composed of urate or uric acid alone or in combination with calcium. In addition, uric acid stones which are uncommon among American children were frequently reported in Asian children.
Keywords: Urolithiasis, Asia, children, urinary metabolic abnormalities, urinary tract infection, chemical stone composition,urological anomalies
Renal calculi (or kidney stones) post surgical intervention from the various hospitals in the Mumbai region were analyzed for the presence biochemical components such as calcium, magnesium, oxalate, phosphate, sulphonamide, cholesterol and carbonate at our department. In this study, we retrospectively analyzed 250 kidney stone samples which were characterized biochemically during the period 2008-2014 to evaluate the predominant component and to establish any correlation which may exist between the biochemical components in these samples and the diet of these patients. The population was statistically analyzed using the Z-proportion test for age, gender and diet; diet was segregated into a moderately non-vegetarian (MNV) and non-vegetarian (NV) and presence of the each of the above components. Majority of the samples presented to our centre were from male subjects. Children were more susceptible to the presence of sulphonaminde and carbonate stones. Women more prone to phosphate stones and moderate non-vegetarians were more prone to calcite stones. Taken together, the data suggest that all three factors age, gender and diet can influence composition of stones.
Physical methods, namely, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) reliably identify specific forms of nephrolithiasis involving a single component such as cystine, 2,8-dihydroxyadenine, xanthine, uric acid, struvite, and drugs as well as common-type stones made of calcium oxalate (CaOx) and/or calcium phosphate. However, for the latter, these methods do not provide etiologic information in clinical practice because a same-stone composition may be the result of very different lithogenic processes. A comprehensive stone analysis method combining morphological examination followed by XRD or FTIR analysis of the core, middle layers, and surface of calculi provides a more complete contribution to etiologic diagnosis than compositional analysis alone. Using this method, stones may be classified into 7 types subdivided in 22 subtypes. Among CaOx stones, type Ic COM calculi are pathognomonic of primary hyperoxaluria. Among calcium phosphate stones, a peculiar morphology of carbapatite stones (type IVa2) is closely associated with distal tubular acidosis, whereas in primary hyperparathyroidism calculi are predominantly made of carbapatite mixed with weddellite or of brushite (type IVd). Ammonium urate calculi of type IIId are found in patients with low phosphate intake and chronic diarrhea due to laxative abuse or in children with endemic urolithiasis. Uric acid calculi are mainly suggestive of low urine pH related to insulin resistance as observed in metabolic syndrome or type 2 diabetes or in case of colon resection. Among common, idiopathic CaOx stones, predominance of whewellite (type I morphology) is mainly associated with high urinary oxalate concentration, whereas predominance of weddellite (type II morphology) is associated with hypercalciuric states. This method is of decisive interest for early diagnosis—and therefore proper treatment—of severe diseases such as primary hyperoxaluria and 2,8-dihydroxyadeninuria.
Background: Adiantum capillus-veneris Linn. is widely used in the management of urolithiasis in Unani system of medicine. Aim: To evaluate the effect of the hydro alcoholic extract of A. capillus-veneris Linn. on calcium oxalate crystallisation by in vitro study. Materials and Methods: The study includes crystallization, nucleation and aggregation assay. Crystallization was induced by addition of 50 μl of 0.1 M sodium oxalate in whole urine in the absence and the presence of extract at different concentrations (0.50 mg, 0.75 mg and 1 mg). The nucleation and aggregation rates were followed at 620 nm after mixing calcium chloride and sodium oxalate solution and in a buffered solution containing calcium oxalate monohydrate crystals, respectively. The rate was evaluated by comparing the slope of turbidity in the presence of extract with that of control using the spectrophotometer. Crystals in the urine were also analysed by light microscopy. Results and Conclusion: Extract of the test drug inhibited the crystallization in solution; less and smaller particles were observed in the presence of extract. These results were further confirmed in the nucleation assay, though the rate of nucleation was not inhibited but number of crystals was found to be decreased. The test drug also inhibited crystal aggregation. It can be concluded therefore, that the test drug possesses significant antilithiasic activity.
Brenner and Rector's The Kidney, edited by Barry Brenner, remains a classic reference in the field of renal diseases. For 20 years, each new edition of this comprehensive text has described all aspects of nephrology from basic science to clinical diagnosis and therapy.
The fifth edition has surpassed the others in size and content. Overall, the new two-volume set has more than 2700 pages, 35 000 references (many recent), and more than 12 000 illustrations and tables. Now, there are more than 120 internationally distingushed contributors. The editor has added new chapters, many involving basic research, and has updated and expanded others. All the while, the authors have maintained the clear and well-organized style and format of previous editions.
The first volume consists of two sections. Section one covers normal renal anatomy and physiology. There are new chapters on embryology, cellular biology, and biochemistry. Other chapters review current knowledge on
A high dietary calcium intake is strongly suspected of increasing the risk of kidney stones. However, a high intake of calcium can reduce the urinary excretion of oxalate, which is thought to lower the risk. The concept that a higher dietary calcium intake increases the risk of kidney stones therefore requires examination.
We conducted a prospective study of the relation between dietary calcium intake and the risk of symptomatic kidney stones in a cohort of 45,619 men, 40 to 75 years of age, who had no history of kidney stones. Dietary calcium was measured by means of a semiquantitative food-frequency questionnaire in 1986. During four years of follow-up, 505 cases of kidney stones were documented.
After adjustment for age, dietary calcium intake was inversely associated with the risk of kidney stones; the relative risk of kidney stones for men in the highest as compared with the lowest quintile group for calcium intake was 0.56 (95 percent confidence interval, 0.43 to 0.73; P for trend, < 0.001). This reduction in risk decreased only slightly (relative risk, 0.66; 95 percent confidence interval, 0.49 to 0.90) after further adjustment for other potential risk factors, including alcohol consumption and dietary intake of animal protein, potassium, and fluid. Intake of animal protein was directly associated with the risk of stone formation (relative risk for men with the highest intake as compared with those with the lowest, 1.33; 95 percent confidence interval, 1.00 to 1.77); potassium intake (relative risk, 0.49; 95 percent confidence interval, 0.35 to 0.68) and fluid intake (relative risk, 0.71; 95 percent confidence interval, 0.52 to 0.97) were inversely related to the risk of kidney stones.
A high dietary calcium intake decreases the risk of symptomatic kidney stones.
The amount of oxalate excreted in urine has a significant impact on calcium oxalate supersaturation and stone formation. Dietary oxalate is believed to make only a minor (10 to 20%) contribution to the amount of oxalate excreted in urine, but the validity of the experimental observations that support this conclusion can be questioned. An understanding of the actual contribution of dietary oxalate to urinary oxalate excretion is important, as it is potentially modifiable.
We varied the amount of dietary oxalate consumed by a group of adult individuals using formula diets and controlled, solid-food diets with a known oxalate content, determined by a recently developed analytical procedure. Controlled solid-food diets were consumed containing 10, 50, and 250 mg of oxalate/2500 kcal, as well as formula diets containing 0 and 180 mg oxalate/2500 kcal. Changes in the content of oxalate and other ions were assessed in 24-hour urine collections.
Urinary oxalate excretion increased as dietary oxalate intake increased. With oxalate-containing diets, the mean contribution of dietary oxalate to urinary oxalate excretion ranged from 24.4 +/- 15.5% on the 10 mg/2500 kcal/day diet to 41.5 +/- 9.1% on the 250 mg/2500 kcal/day diet, much higher than previously estimated. When the calcium content of a diet containing 250 mg of oxalate was reduced from 1002 mg to 391 mg, urinary oxalate excretion increased by a mean of 28.2 +/- 4.8%, and the mean dietary contribution increased to 52.6 +/- 8.6%.
These results suggest that dietary oxalate makes a much greater contribution to urinary oxalate excretion than previously recognized, that dietary calcium influences the bioavailability of ingested oxalate, and that the absorption of dietary oxalate may be an important factor in calcium oxalate stone formation.
Urinary stones in children are usually genetic and most commonly due to hypercalciuria. Symptoms of urolithiasis in children differ among age groups. Isolated hematuria in children may be caused by hypercalciuria and precede calculus formation. Careful evaluation successfully identifies the cause of urinary stones in most children, although diagnostic criteria may vary in different age groups. Therapies should be targeted to the underlying diagnosis.
The contribution of ascorbate to urinary oxalate is controversial. The present study aimed to determine whether urinary oxalate and pH may be affected by vitamin C supplementation in calcium stone-forming patients.
Forty-seven adult calcium stone-forming patients received either 1 g (N=23) or 2 g (N=24) of vitamin C supplement for 3 days and 20 healthy subjects received 1 g. A 24-hour urine sample was obtained both before and after vitamin C for calcium, oxalate, magnesium, citrate, sodium, potassium, and creatinine determination. The Tiselius index was used as a calcium oxalate crystallization index. A spot fasting morning urine sample was also obtained to determine the urinary pH before and after vitamin C.
Fasting urinary pH did not change after 1 g (5.8 +/- 0.6 vs. 5.8 +/- 0.7) or 2 g vitamin C (5.8 +/- 0.8 vs. 5.8 +/- 0.7). A significant increase in mean urinary oxalate was observed in calcium stone-forming patients receiving either 1 g (50 +/- 16 vs. 31 +/- 12 mg/24 hours) or 2 g (48 +/- 21 vs. 34 +/- 12 mg/24 hours) of vitamin C and in healthy subjects (25 +/- 12 vs. 39 +/- 13 mg/24 hours). A significant increase in mean Tiselius index was observed in calcium stone-forming patients after 1 g (1.43 +/- 0.70 vs. 0.92 +/- 0.65) or 2 g vitamin C (1.61 +/- 1.05 vs. 0.99 +/- 0.55) and in healthy subjects (1.50 +/- 0.69 vs. 0.91 +/- 0.46). Ancillary analyses of spot urine obtained after vitamin C were performed in 15 control subjects in vessels with or without ethylenediaminetetraacetic acid (EDTA) with no difference in urinary oxalate between them (28 +/- 23 vs. 26 +/- 21 mg/L), suggesting that the in vitro conversion of ascorbate to oxalate did not occur.
These data suggest that vitamin C supplementation may increase urinary oxalate excretion and the risk of calcium oxalate crystallization in calcium stone-forming patients.
684 This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the author's clinical recommendations. A 39-year-old man reports an eight-hour history of colicky pain in the right lower quadrant radiating to the tip of his penis. He had previously had a kidney stone, which passed spontaneously. Physical examination shows that he is in distress, is afebrile, and has tenderness of the right costovertebral angle and lower quadrant. Urinalysis shows microhematuria. Helical computed tomography (CT) of the abdomen and pel-vis shows a 6-mm calculus of the right distal ureter and mild hydroureteronephrosis. How should this patient be treated? Up to 12 percent of the population will have a urinary stone during their lifetime, and recurrence rates approach 50 percent. 1 In the United States, white men have the highest incidence of stones, followed in order by white women, black women, and black men. 2,3 Fifty-five percent of those with recurrent stones have a family history of urolith-iasis, 4 and having such a history increases the risk of stones by a factor of three. 5 The classic presentation of a renal stone is acute, colicky flank pain radiating to the groin. As the stone descends in the ureter, the pain may localize in the abdominal area overlying the stone and radiate to the gonad. Peritoneal signs are absent. As the stone approaches the ureterovesical junction (Fig. 1), lower-quadrant pain radiating to the tip of the urethra, urinary urgency and frequency, and dysuria are characteristic, mimick-ing the symptoms of bacterial cystitis. Physical examination typically shows a patient who is often writhing in distress, trying to find a comfortable position. Tenderness of the costovertebral angle or lower quadrant may be present. Gross or microscopic hema-turia occurs in approximately 90 percent of patients; however, the absence of hematuria does not preclude the presence of stones. 6 Owing to the shared splanchnic innervation of the renal capsule and intestines, hydronephrosis and distention of the renal capsule may produce nausea and vomiting. Thus, acute renal colic may mimic acute abdominal or pelvic conditions.
In older women and men, greater intakes of dietary calcium, potassium, and total fluid reduce the risk of kidney stone formation, while supplemental calcium, sodium, animal protein, and sucrose may increase the risk. Recently, phytate has been suggested to play a role in stone formation. To our knowledge, no prospective information on the role of dietary factors and risk of kidney stone formation is available in younger women.
We prospectively examined, during an 8-year period, the association between dietary factors and the risk of incident symptomatic kidney stones among 96 245 female participants in the Nurses' Health Study II; the participants were aged 27 to 44 years and had no history of kidney stones. Self-administered food frequency questionnaires were used to assess diet in 1991 and 1995. The main outcome measure was an incident symptomatic kidney stone. Cox proportional hazards regression models were used to adjust simultaneously for various risk factors.
We documented 1223 incident symptomatic kidney stones during 685 973 person-years of follow-up. After adjusting for relevant risk factors, a higher dietary calcium intake was associated with a reduced risk of kidney stones (P =.007 for trend). The multivariate relative risk among women in the highest quintile of intake of dietary calcium compared with women in the lowest quintile was 0.73 (95% confidence interval, 0.59-0.90). Supplemental calcium intake was not associated with risk of stone formation. Phytate intake was associated with a reduced risk of stone formation. Compared with women in the lowest quintile of phytate intake, the relative risk for those in the highest quintile was 0.63 (95% confidence interval, 0.51-0.78). Other dietary factors showed the following relative risks (95% confidence intervals) among women in the highest quintile of intake compared with those in the lowest quintile: animal protein, 0.84 (0.68-1.04); fluid, 0.68 (0.56-0.83); and sucrose, 1.31 (1.07-1.60). The intakes of sodium, potassium, and magnesium were not independently associated with risk after adjusting for other dietary factors.
A higher intake of dietary calcium decreases the risk of kidney stone formation in younger women, but supplemental calcium is not associated with risk. This study also suggests that some dietary risk factors may differ by age and sex. Finally, dietary phytate may be a new, important, and safe addition to our options for stone prevention.
Nephrolithiasis is a complex phenotype that is influenced by both genetic and environmental factors. We conducted a large twin study to examine genetic and nongenetic factors associated with stones.
The VET Registry includes approximately 7500 male-male twin pairs born between 1939 to 1955 with both twins having served in the military from 1965 to 1975. In 1990, a mail and telephone health survey was sent to 11,959 VET Registry members; 8870 (74.2%) provided responses. The survey included a question asking if the individual had ever been told of having a kidney stone by a physician. Detailed dietary habits were elicited. In a classic twin study analysis, we compared concordance rates in monozygotic (MZ) and dizygotic (DZ) twins. We also conducted a cotwin control study of dietary risk factors in twins discordant for stones.
Among dizygotic twins, there were 17 concordant pairs and 162 discordant pairs for kidney stones. Among monozygotic twins, there were 39 concordant pairs and 163 discordant pairs. The proband concordance rate in MZ twins (32.4%) was significantly greater than the rate in DZ twins (17.3%) (chi(2)= 12.8; P < 0.001), consistent with a genetic influence. The heritability of the risk for stones was 56%. In the multivariate analysis of twin pairs discordant for kidney stones, we found a protective dose-response pattern of coffee drinking (P= 0.03); those who drank 5 or more cups of coffee were half as likely to develop kidney stones as those who did not drink coffee (OR = 0.4, 95% CI 0.2, 0.9). Those who drank at least 1 cup of milk per day were half as likely to report kidney stones (OR = 0.5, 95% CI 0.3, 0.8). There were also marginally significant protective effects of increasing numbers of cups of tea per day and frequent consumption of fruits and vegetables. Other factors such as the use of calcium supplements, alcohol drinking, consumption of solid dairy products, and the amount of animal protein consumed were not significantly related to kidney stones in the multivariate model. Conclusion: These results confirm that nephrolithiasis is at least in part a heritable disease. Coffee, and perhaps tea, fruits, and vegetables were found to be protective for stone disease. This is the first twin study of kidney stones, and represents a new approach to elucidating the relative roles of genetic and environmental factors associated with stone formation.
A body of evidence establishes that the occurrence of kidney stone disease has increased in some communities of industrialized countries. Information on recent temporal trends in the United States is lacking and population-based data on epidemiologic patterns are limited. Study objective was to determine whether kidney stone disease prevalence increased in the United States over a 20-year period and the influence of region, race/ethnicity, and gender on stone disease risk.
We measured the prevalence of kidney stone disease history from the United States National Health and Nutrition Examination Survey (II and III), population-based, cross-sectional studies, involving 15,364 adult United States residents in 1976 to 1980 and 16,115 adult United States residents in 1988 to 1994.
Disease prevalence among 20- to 74-year-old United States residents was greater in 1988 to 1994 than in 1976 to 1980 (5.2% vs. 3.8%, P < 0.05), greater in males than females, and increased with age in each time period. Among 1988 to 1994 adults, non-Hispanic African Americans had reduced risk of disease compared to non-Hispanic Caucasians (1.7% vs. 5.9%, P < 0.05), and Mexican Americans (1.7% vs. 2.6%, P < 0.05). Also, age-adjusted prevalence was highest in the South (6.6%) and lowest in the West (3.3%). Findings were consistent across gender and multivariate adjusted odds ratios for stone disease history, including all demographic variables, as well as diuretic use, tea or coffee consumption, and dietary intake of calcium, protein, and fat did not materially change the results.
Prevalence of kidney stone disease history in the United States population increased between 1980 and 1994. A history of stone disease was strongly associated with race/ethnicity and region of residence.
http://www.kidney.niddk.nih.gov/ NIH Publication No
National Kidney and Urologic Diseases Information Clearing
House (NKUDIC). http://www.kidney.niddk.nih.gov/ NIH
Publication No. 08–2495 October 2007
Renal and biliary calculi: Practical Biochemistry
- G Rajagopal
- Bd Toora
Rajagopal G, Toora BD: Renal and biliary calculi: Practical
Biochemistry (2 nd ed), Ahuja publishing house, 2005; 163-6.
Kidney stone health center ( www.kidney.org)
- Monica Rhodes
Monica Rhodes. Kidney stone health center ( www.kidney.org)