Saudi Journal of Kidney Diseases and Transplantation

: 2013  |  Volume : 24  |  Issue : 3  |  Page : 630--637

Twenty-four-hour urine constituents in stone formers: A study from the northeast part of Peninsular Malaysia

NS Hussein1, SM Sadiq1, MD Kamaliah2, AW NorAkmal3, MN Gohar1,  
1 Department of Surgery, School of Medical Sciences, Hospital Univeristi Sains Malaysia, Kelantan, Kota Bharu, Malaysia
2 Department of Medicine, School of Medical Sciences, Hospital Univeristi Sains Malaysia, Kelantan, Kota Bharu, Malaysia
3 Department of Chemical Pathology, School of Medical Sciences, Hospital Univeristi Sains Malaysia, Kelantan, Kota Bharu, Malaysia

Correspondence Address:
N S Hussein
Post Office 7 Abkar, Box No. 26047, Baghdad, Iraq


Urolithiasis is a common disease with increasing incidence and prevalence world­wide, probably more common in industrialized countries. The metabolic evaluation of 24-h urine collection has been considered as part of the management of urinary stone patients. The aim of this study was to evaluate the 24-h urine constituents in stone formers and its relation to demographic data in the northeast part of Peninsular Malaysia. One hundred and six patients were recruited in this study from two hospitals in the same geographical region; 96 patients fulfilled the inclusion criteria and an informed consent was obtained from all subjects. The 24-h urine was collected in sterile bottles with a preservative agent and calcium, oxalate, citrate, uric acid, magnesium and phosphate were tested using commercial kits on a Roche Hitachi 912 chemistry analyzer. The age (mean ± SD) of 96 patients was 56.45 ± 13.43 years and 82.3% of the patients were male while 17.7% were female. The 24-h urine abnormalities were hypercalciuria (14.5%), hyperoxaluria (61.4%), hypocitraturia (57.2%), hyperuricouria (19.7%), hypomagnesuria (59.3%) and hyperphosphaturia (12.5%). Hyperoxaluria (61.4%) was the most common abnormality detected during the analysis of 24-h urine constituents in contradiction to industrial countries, where hypercalciuria was the most common finding. The high frequencies of hypomagnesuria and hypocitraturia reflect the important role of magnesium and citrate in stone formation and their prophylactic role in the treatment of urinary stone disease in the given population.

How to cite this article:
Hussein N S, Sadiq S M, Kamaliah M D, NorAkmal A W, Gohar M N. Twenty-four-hour urine constituents in stone formers: A study from the northeast part of Peninsular Malaysia.Saudi J Kidney Dis Transpl 2013;24:630-637

How to cite this URL:
Hussein N S, Sadiq S M, Kamaliah M D, NorAkmal A W, Gohar M N. Twenty-four-hour urine constituents in stone formers: A study from the northeast part of Peninsular Malaysia. Saudi J Kidney Dis Transpl [serial online] 2013 [cited 2022 Aug 7 ];24:630-637
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Full Text


Urolithiasis is a common disease with an in­creasing incidence and prevalence worldwide, being even more common in industrialized countries. The risk of urinary stone is 5-9% in Europe, 3% in North America, 1-4% in Asia and 20% in the oil-rich states of Arabian Gulf. [1] However, in studies performed locally, the prevalence of urinary stone disease in Kelantan seems to be in the range of 9.8-37 per 100,000 population. [2],[3],[4] Metabolic evaluation of 24-h urine is considered as a part of management of urinary stone patients. To the best of our knowledge, in Malaysia, there are no pub­lished data on 24-h urinary biochemical composition for stone former subjects for our day-to-day clinical practice. We had to use referen­ces from other countries. This prospective study was carried out to analyze the 24-h urine meta­bolic constituents in stone formers and their relation to the demographic data of our cohort.

 Materials and Methods

Approval was obtained from the Research and Ethical Committee in our medical school to conduct this prospective cohort study. Informed consent was obtained from all pa­tients. Inclusion criteria was a patient who is a first or recurrent stone former, single or mul­tiple stone, diagnosed by plain X-ray of the kidney, ureter and bladder (KUB), intravenous urography and/or KUB ultrasound. Exclusion criteria were children under 13 years old, pregnant women, urine output less than 1000 mL/24 h and chronic kidney disease with creatinine clearance less than 30 mL/min/1.37 m 2 using the Cockcroft and Gault formula.

 Definition of Demographic Data

Occupations of subjects were classified into manual and office workers. The geographical residences of participants were identified at the time of sample collection and divided into coastal and inland areas.

The drinking water of subjects was defined upon the source of their supply system: go­vernment piped water, river water and private well water. Twenty-four-hour urine was col­lected from 9:00 am to the following 9:00 am, either at home or as an in-patient before sur­gical interference. All subjects were on normal diet and no special instructions were given to restrict food or fluid intake during the col­lection period (as 24-h urinary chemical ana­lysis was not a routine procedure in our institute).

All patients were advised to avoid allopurinol, potassium citrate, thiazide and any other medi­cations known to affect study parameters seve­ral days before collection. The 24-h urine sam­ples were collected into a plastic container containing 3 mmol/L of sodium azide as a preservative agent. All specimens were analyzed on the same day of collection except for citrate and oxalate. Urine pH was determined using dip sticks as soon as possible and the urine volume was recorded. Urine from each subject was distributed into two vials, one with hydrochloric acid (10 mmol) as preservative, and samples were stored at -20°C until being analyzed for citrate and oxalate. Another vial was analyzed immediately for calcium, uric acid, magnesium and phosphorus. Urine sample was also collected in a sterile container for culture and sensitivity. Urinary calcium was determined by the complexometric method and urinary phosphate, uric acid and urinary magnesium were assayed by the calorimetric method using a commercial kit on the Roche Hitachi 912 auto analyzer. Commercial kits on the Roche Hitachi 912 auto analyzer and spectrophotometer were used to determine urinary oxalate and urinary citrate. All 24-h urinary analyses were conducted in our medical laboratory according to their rou­tine protocols.

 Data Analysis

Data were analyzed using Statistical Package of Social Science (SPSS) version 11 (SPSS Inc., Chicago, IL, USA) for Windows. Student t-test was used for analyzing the difference between the two groups in the normal distri­bution. One-way ANOVA was used to com­pare more than two means of different con­tinuous variables between the study groups. When a significant difference was detected between any of the numerical variables using this test (one-way ANOVA), the Scheffe test was used to demonstrate in which study groups these differences had occurred.

The Chi-square (X 2 ) test was used to com­pare the frequencies of the two categorical group variables. Level of significance (α) was set at 0.05 and P-value <0.05 was accepted as significant.


We collected 24-h urine from 106 stone formers from two different hospitals in the same geo­graphical area (Kelantan 700 km northeast of Peninsular Malaysia). However, only 96 pa­tients fulfilled the inclusion criteria and were recruited into the study.

Ten patients were excluded from the study because the 24-h urine was less than 1000 mL. The mean (±SD) age of our patients was 56.45 (13.43) years, range 24-80 years. Seventy-nine patients (82.3%) were male and 17 (17.7%) patients were female. The Malay group repre­sented 95.8% (92) of our population, and only 3.1% (3) were from other ethnic groups (two Chinese and one Indian). 62.5% (60) were office workers and 37.5% (36) were manual workers.

29.2% (28) were inhabitants of coastal areas and 70.8% (68) were from inland areas. The sources of drinking water for 54.2% (52) of the patients were from government piped water, 37.5% (36) subjects were using well water and 8.3% (8) subjects were using river water.

Twelve of the 96 patients (12.5%) had positive urine culture (10/79 male and 2/17 female). Among them, three (25%) patients were having gram positive organisms and nine (75%) pa­tients had gram negative organisms.

Forty-five (46.9%) patients of the study population has acidic urine pH (less than 6.0) and 51 (53.1%) had alkaline urine pH (more than 9.0). The female stone formers were more likely to have alkaline urinary pH compared with male stone formers.

The reference and percentages of 24-h urine constituents are shown in [Table 1] and [Table 2]. The relation between the mean and the standard de­viation of the 24-h urine constituents and de­mographic data of stone formers [Table 3], [Table 4], [Table 5], [Table 6], [Table 7] and [Table 8] showed that there was a statistical difference between 24-h urine citrate excretion in the office and manual workers, uric acid and mag­nesium excretion in the inland and coastal inhabitants and magnesium excretion in male and female. However, when we compared the proportion of normal and hypocitatricuria bet­ween the office and manual workers, there was no significant difference (P = 0.40). In addition, there was no significant difference (P = 0.41) when we compared the proportion of normal and hypomagnesiuria in the male and female populations.{Table 1}{Table 2}{Table 3}{Table 4}{Table 5}{Table 6}{Table 7}{Table 8}


A 24-h urine collection, part of the metabolic evaluation in patients with urolithiasis, to date, is still the gold standard for metabolic evalua­tion in urinary stone disease. [5]

Many published series noted that urinary stone disease is more common in males than in females. In an epidemiological survey on urolithasis in Germany, it was reported that the ratio of males to female was found to be 1.4:1. [6] The male to female ratio in our study was 4.6:1, which was in agreement with the studies of Sreenevasan et al and Nazmi et al. Both these authors reported the male to female ratio in Malay subjects to be 5:1 and 2:1, respectively. [3],[6]

Several published studies have shown that there was a relation between gender and 24-h urine metabolic abnormalities. Yagisawa et al [7] reported that hyperoxaluria, hyperuricosuria, hypercalciuria and hypocitraturia were more frequent in the male gender and that urinary volume was significantly lower in females. However, Sarda et al [8] concluded that hypercalciuria and hyperoxaluria were more com­mon in males and high excretion of citrate was observed in female stone formers.

Our findings here had no obvious difference in either sex with regard to calcium, oxalate and citrate excretion, but male subjects had the propensity to excrete more uric acid compared with female stone formers in our population. [2] It is generally believed that an increased amount of fluid intake is associated with reduced stone formation probably through its dilution effect, which consequently reduces the urinary satura­tion levels. [9]

Both hard and soft water can increase or decrease stone formation, which seems to be the biggest puzzling concern for stone former patients. Early studies demonstrated that the ingestion of hard water is a contributing factor in urinary stone formation by increasing the excretion of urinary calcium. [10] However, ano­ther study showed that patients who lived in areas with a hard water supply had less urolithitasis formation. [11]

On the other hand, some researchers believe that ingestion of hard water without food compared with soft water may increase urinary calcium excretion. [12] In our study, the identifi­cation of hard and soft water were only pre­sumptive, and defining a definite link was not possible.

There was no precise and published data about the mineral composition of these three types of local water. However, our study showed no impact of all these three types of water on the constituents of 24-h urine. This finding is in accordance with the findings of Bradley et al, [11] who concluded that the asso­ciation between water hardness and urinary stone disease is still unclear.

The debate about the relationship between nature of work and urinary stone disease seems to be continued. Some researchers found that urinary stones are more likely to occur in individuals who have a sedentary job. In the Royal Navy, the highest incidences were found in cooks and engine room personnel. [13] How­ever, Fatemeh et al [14] found that workers who are chronically exposed to a hot environment and significant sweating are at greater risk of urinary stones.

In our subjects, no significant differences were found in urinary biochemical parameters between office and manual workers. A similar finding was reported by Akea et al, [15] stating that there were no significant differences in the prevalence of urinary stone between those two groups of workers.

Several lines of evidence suggest that hypercalciuria is directly involved in the pathogenesis of stone formation. In this study, we did not look for the cause of hypercalciuria and, therefore, we could not specify whether it was absorptive, resorptive or renal hypercalciuria. Surprisingly, the frequency of hypercalciuria in our study was totally different from that in other studies. Only 15.2% of the males and 11.8% of the females in our study popu­lation was hypercalciuric. However, Yagisawa et al and Mittal et al [7],[16] reported the incidence of hypercalciuria to 45.9% and 28%, respec­tively, for first stone former and 58.1% and 46%, respectively, for recurrent stone former. Our finding was in close agreement to the finding from Thailand by Sriboonlue et al [17] and the finding from Turkey by Esen, [18] where both authors reported a low incidence of hypercalciuria (15% and 24%, respectively).

Hypercalciuria is a multifactorial disorder; therefore, it is difficult to give a satisfactory explanation. However, in our subjects, the low frequency of hypercalciuria may be due to presence of stone fragments in the urinary tract that attract urinary calcium to participate in the crystallization process as many researchers have recommended metabolic evaluation to be performed in stone-free patients. [19] In our study group, low consumption of milk and milk pro­ducts, low sodium intake or excessive sodium loss through sweating as hot climate may contribute to low calcium excretion, which is in agreement with other studies [20] that reported that the low Na/Ca excretion ratio found in this population might be an important factor in the pathogenesis of urinary stone.

An increase in urinary oxalate excretion is a much more important determinant for forma­tion of calcium oxalate stone than a similar increase in urinary calcium. [21] In this study, the hyperoxaluria was the most common meta­bolic disorder. Hyperoxaluira was present in 57% of the male and 82% of the female pa­tients. This finding is in accordance with the result of the Milttal et al [16] study, which re­vealed that 58% of first stone formers and 68% of recurrent stone formers have hyperoxaluria. Similar results were seen in a study from Kumar et al, [22] where hyperoxaluria was found in 55% and 61% first and recurrent stone formers, respectively.

It is reported in most published series [23] that a high dietary calcium intake decreases the ab­sorption of oxalate in the intestinal lumen by making complexes with calcium. It seems pro­bable that in our patients, the increased oxalate excretion is due to a fall in the intraluminal calcium concentration. This fact could be attri­buted to the poor consumption of calcium-rich food or it might be the consequences of a high intake of oxalate-rich food. [24]

There are controversial data about the excre­tion of urinary citrate in stone formers. Hosking et al [25] showed that the difference in urinary citrate excretion among healthy individual and stone formers was not statistically significant. In contrast, other researchers [22] have found a significant difference between stone formers and controls.

In this study, the second most striking finding ding after hyperoxaluria was hypocitraturia and hypomagnesuria. In our patients, a high percentage of hypocitraturia (57.3%) was noted, which was in accordance with the findings of Kumar et al [22] and Esen et al, [18] where hypocitraturia, respectively, was noted in 55% and 44.9% of the stone formers. The relatively high occurrence of citrate depletion in our pa­tients remains unclear; perhaps, it is multifactorial. In some patients, the exact cause of hypocitraturia is unknown, which is known as idiopathic hypocitraturia. The prevalence of idiopathic hypocitraturic nephrolithiasis varies from 50% to 93%. [26]

Hot weather may be one factor that induces loss of potassium via sweating, and the asso­ciation between potassium depletion and hypocitraturia has been reported. It has been found that 75% of the hypocitraturic patients were concomitantly having hypokaliuria. [26] Even though loss of potassium via sweating is low, it might contribute substantially to a potassium-depleted state when sweating is excessive and/or intake is low. [26]

Another possible reason for hypocitraturia may be the effect of thiazide diuretrics, as it is a well know therapy for reducing the hypercalciuric state in stone formers. Numerous resear­chers reported that thiazade diuretrics may reduce citrate excretion probably by causing hypokalemia and intracellular acidosis. [27]

The levels of urinary magnesium in urinary stone formers described in the literature are also variable, with the reported prevalence of hypomagnesuria varying between 8.8% and 24.4%. [16] Oral intake of magnesium will dec­rease the oxalate absorption and urinary excre­tion in a manner similar to calcium by binding to oxalate in the gut. [22] However, a few studies have examined the effect of magnesium sup­plementation on stone recurrence. In some prospective, observational studies, higher die­tary magnesium was associated with a 30% lower risk of stone formation in men but not in women. [28],[29]

79.8% was the highest incidence of hyperuricosuria reported by El-Reshaid et al. [30] On the contrary, Mittal et al [16] found that only 7% of adult stone formers had hyperuricosuria; however, our rate of 19.8% is still low in comparison with the rates of affluent countries. Economics, food composition and genetic and environmental factors contribute to these va­riations in the incidence of hyperurcosuria.

Hyperphosphaturia is closely associated with urinary metabolic abnormalities. The reported incidence of hyperphosphaturia in stone for­mers was 19.9%, [31] whereas in our study it was 12.5%. This low rate may be due to dietary habit and life style variations.

The most common biochemical abnormalities observed in our study were hyperoxaluria, hypomagnesuria and hypocitraturia, in contra­diction to Western countries, where 50-70% of stone formers have hypercalciuria. [32] The high frequency of hypomagnesuria and hypocitraturia reflect the important role of magnesium and citrate in stone formation and prophylactic therapy, with magnesium and citrate having a role in the treatment of urinary stone disease in our population. The limitation of our study is that it represents only one geographical area of Peninsular Malaysia and also that the number of patients in our cohort is small.


1Ramello A, Vitale C, Margella M. Epidemio­logy of nephrolithiasis. J Nephrol 2000;13 Suppl 3:65-70.
2Lim KG, Edward RH, McAll GL, Thaung M, Wahad NA, Arimainayagam G. Urinary stone in Kelantan . Malaysia: A two year review. Singapore Med J 1988;29:353-6 .
3Sreenevasan G. Incidence of urinary stones in the various states of mainland Malaysia. Med J Malaysia 1981;36:142-7.
4Nazmi N, Zainal D, Hashim M. Renal stone in Kelantan . Malaysia: Has the pattern changed?. Southeast Asian J Trop Med Public Health 1997;28:641-4.
5Ogawa Y, Yonou H, Hokama S, Oda M, Morozumi M, Sugaya K. Urinary saturation and risk factors for calcium oxalate stone disease based on spot and 24-hour urine spe­cimens. Front Biosci 2003;8:a167-76.
6Hess A, Brandle E, Wilbert D, Kohrmann KU, Alken P. Study on The prevalence and incidence of urolithiasis in Germany comparing the years 1979 vs 2000. Eur Urol 2003;44:709-13.
7Yagisawa S, Chandhoke PS, Fan J. Metabolic risk factors in Patients with first -time and recurrent stone formation as determined By comprehensive metabolic evaluation. Urology 1998;52:750-5.
8Sarada B, Satyanarayana U. Urinary compo­sition in men and women and the risk of urolithiasis. Clin Biochem 1991;24:487-90.
9Borghi L, Schianchi T, Meschi T, et al. Comparison of two diets for prevention of recurrent stones in idiopathic hypercalciuria. N Engl J Med 2002;346:77-84.
10Shuster J, Finlayson B, Scheaffer R, Sierakowski R, Zolktek J, Dzegede S. Water hard­ness and urinary stone disease. J Urol 1982; 128:422-5 .
11Bradley S, Noah S, Jeremy B, Stephen L, Marshall S. Calcium nephrolithasis: Effect of water hardness on urinary electrolytes. Urology 2002;60:23-7.
12Bellizzi V, Nicola L, Minutolo R, et al. Effects of water hardness on urinary risk factors for kidney stones in patients with idiopathic nephrolithiasis. Nephron 1999;81:66-70.
13Alexander C. Urology in military practice. Journal of the Australian defence health service. ADF Health, 2001;2:75-9.
14Fatemeh S, Farangis S, Alice K, et al. Personal characteristic and Urinary stones. Hong Kong J Nephrol 2009;11:14-9.
15Akea M, Esen T, Tellaloglu S. Urinary stone disease in Turkey: An update epidemiology study. Eur Urol 1991;20:240-3.
16Mittal RD, Kumar R, Mitall B, Prasad R, Bhandari M. Stone composition, metabolic profile and presence of the gut-inhabiting bacterium oxalobacter formigenes as risk factors for renal stone formation. Med Princ Pract 2003;12:208-13.
17Sriboonlue P, Prasongwatana V, Tungsanga K, et al. Blood and urine aggregator and inhibitor composition and renal -patients from North­eastern Thailand. Nephron 1991;59:591-6.
18Esen T, Akinci M, Tellaloglu S, Kocak T. Role of inhibitor deficiency on urolithiasis. Eur Urol 1991;19:244-8 .
19Laube N, Pullmann M, Hergarten S, Hesse A. Influences of urinary stones on the compo­sition of a 24-hour urine sample. Clin Chem 2003;49:281-5.
20Nilwarangkur S, Malasi P, Nimmannit S, et al. Urinary constitutes in an endemic area of stones and renal tubular acidosis in north­eastern Thailand. Southeast Asian J Trop Med Public Health 1990;21:437-40.
21El-Shall H, Jeon Jin hwan, Abdel-Aal E A, Khan S, Gower L, Rabinovich Y. A study of primary nucleation of calcium oxalate mono­hydrate: II. Effect of urinary species Cryst Res Technol 2004;39:222-9.
22Kumar R, Kapoor R, Mittal B, Kumar A, Mittal RD. Evaluation of urinary abnormalities in urolithiasis patients: A study from north India. Indian J Clin Biochem 2003;18:209-15.
23Liebman M, Costa G. Effect of calcium and magnesium on urinary oxalate excretion after oxalate loads. J Urol 2000;163:1565-9.
24Siener R, Eber D, Nicolay C, Hesse A. Dietary risk factor for hyperoxaluria in stone formers. Kidney Int 2003;63:1037-43.
25Hosking DH, Wilson JW, Liedtke RR, Smith LH, Wilson DM. Urinary citrate excretion in normal persons and patients with idiopathic calcium urolithiasis. J Lab Clin Med 1985;106: 682-9.
26Tungsanga K, Sriboonlue P, Bornwornpadungkitti S, Tosukhowong P, Sitprija V. Urinary acidification in renal stone patients from Northeastern Thailand. J Urol 1992;147:325-8.
27Wuermser LA, Reilly C, Poindexter JR, Sakhaee K, Pak CY. Potassium-magnesium citrate versus potassium chloride in thiazide - induced hypokalemia. Kidney Int 2000;57:607-12.
28Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: New insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32.
29Curhan GC, Willett WC, Knight EL, Stampfer MJ. Dietary factors and the risk of incident kidney stones in younger women (Nurses' Health Study II). Arch Intern Med 2004;164: 885-91.
30El-Rashaid K, Mughal H, Kapoor M. Epidemiological profile, mineral metabolic pattern and crystallography analysis of urolithiasis in Kuwait. Eur J Epidemiol 1997;13:229-34.
31Yong-June K, Chae Y, Yun SJ, et al. Phosphaturia as a promising predictor for recurrent stone formation in patients with urolithiasis. J Urol 2009;181:519.
32Stitchantrakul W, Kochakarn W, Ruangraksa C, Domrongkitchaiporn S. Urinary risk factors for recurrent calcium stone formation in Thai Stone Formers. J Med Assoc Thai 2007;90: 688-98.