• Kidney Research and Clinical Practice
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• v.37 no.4
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• pp.373-383
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• 2018

Background: Several epidemiologic studies have suggested that the urine sodium excretion (USE) can be estimated in lieu of performing 24-hour urine collection. However, this method has not been verified in patients with chronic kidney disease (CKD) or in an interventional study. The purpose of this study was to evaluate the usefulness of estimating USE in a prospective low-salt diet education cohort (ESPECIAL). Methods: A new formula was developed on the basis of morning fasting urine samples from 228 CKD patients in the ESPECIAL cohort. This formula was compared to the previous four formulas in the prediction of 24-hour USE after treatment with olmesartan and low-salt diet education. Results: Most previously reported formulas had low predictability of the measured USE based on the ESPECIAL cohort. Only the Tanaka formula showed a small but significant bias (9.8 mEq/day, P < 0.05) with a low correlation (r = 0.34). In contrast, a new formula showed improved bias (-0.1 mEq/day) and correlation (r = 0.569) at baseline. This formula demonstrated no significant bias (-1.2 mEq/day) with the same correlation (r = 0.571) after 8 weeks of treatment with olmesartan. Intensive low-salt diet education elicited a significant decrease in the measured USE. However, none of the formulas predicted this change in the measured urine sodium after diet adjustment. Conclusion: We developed a more reliable formula for estimating the USE in CKD patients. Although estimating USE is applicable in an interventional study, it may be unsuitable for estimating the change of individual sodium intake in a low-salt intervention study.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.23-32
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• 1975

In order to study the dally metabolism of sodium chloride and of nitrogen, 24-hour urine samples were collected from 1,593 normal Korean females whose ages varied from 2 to 80 years old. The volume, the concentration of chloride and the osmolality of the urine, add the total nitrogen were determined, along with the resting pulse rate and the blood pressure. The daily urine volume was maintained at $1,000{\sim}1,300\;ml/m^2/day$ in all age groups while the chloride concentration and osmolality of the urine samples were approximately 200 mEq/liter and 600 milliosmoles, respectively, in most of age groups. Hence the daily urinary output of sodium chloride was estimated to be approximately $15g/m^2$/day in adult groups. On the other hand, the daily excretion of total nitrogen amouted to approximately $5{\sim}6g/m^2/day$. These findings indicated that the average Korean females live on low-protein and high-salt diets throughout their life. Despite a known correlation between the incidence of hypertension and the high salt intake, none of the subjects employed in this work showed any sign of hypertension.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.229-235
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• 1986

Lithium salts are being used increasingly to treat patient with affective disorders, especially acute mania, or bipolar manic-depressive illness. For therapeutic effect the lithium content must be maintained at or above a particular level. Lithium poisoning due to overdosage may be seen occasionally, and its course is determined primarily by the rate of renal lithium elimination. A search is therefore indicated for procedures that could raise the lithium clearance. In a number of reports renal lithium excretion has been studied in relation to the excretion of water, sodium, potassium and hydrogen, but effects of sodium or water on the lithium excretion has not yet been clarified. Hence the present study was undertaken to investigate the effects of corticosteroid on the excretion of lithium ion. The female rat(Sprague-Dowley), weighing from 200 to 300g, was injected with 50mg/kg of lithium chloride intraperitoneally, and then injected with graded dosage of fludrocortisone and dexamethasone in each group. During the injected rats were incubated in metabolic cage, 24 hour urine of rats were collected. At 24 hours after injection, the rats were sacrificed with guillotin, the blood were collected. And then the concentratios of $Na^+$, $K^+$, $Li^+$ of collected urine and serum were checked by Flame photometer. The results are summarized as follows; 1. Fludrocortisone decreased the serum concentration of lithium and increased the urinary excretion of lithium. 2. In the group treated with low dose of dexamethasone(0.1mg/kg), the serum concentration of lithium was decreased and high dose of dexamethasone (1mg/kg) increased the urinary excretion of lithium. 3. Fludrocortisone increased the urinary $[Na^+]/[K^+]$ in serum and decreased $[Na^+]/[K^+]$ in urine, but opposite effects were occurred in dexamethasone. By above results, it may be concluded that corticosteroid increased the urinary excretion of lithium and decreased the serum concentration of lithium, but it seems to be there is no relationship between these effects of corticosteroid and of the renal $Na^+$ or $K^+$ transport.

• Journal of Nutrition and Health
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• v.18 no.3
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• pp.194-200
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• 1985

The purpose of this study was to investigate sodium intake and protein metabolism for pregnant women in Korea. The relationship between salt consumption and hypertension, electrolyte changes in pregnancy, and the tendency of weight gain of pregnant women were also examined. The dietary survey and twelve or twenty-four hour's urine collection was performed in this study. The subjects were pregnant women who came to gynecology clinic for prenatal care from July to August in 1984. The results were as follows: 1) Intakes of calorie and iron of Korean pregnant women were 2,036 Kcal and 16mg per day per person. The calorie composition consists of 65% carbohydrate, 16% protein, and 19% lipids. The average level of all nutrients was about 87% of Korean Recommended Dietary Allowances. 2) The sodium intakes in pregnant women estimated by dietary survey was 318.6 mEq Na (7,966 mg Na), which is equivalent to 20.2 g NaCl. 3) Daily sodium excretion was 112.5 mEq per liter, that is equal to 147.4 mEq. Potassium excretion was 24.95 mEq per liter and creatinine excretion was 594.0 mg per day. 4) There were statistically significant correlations between sodium intake and the excretions of sodium, potassium and creatinine. The blood pressure was positively correlated with sodium intakes. As sodium and potassium ratio was increased, systolic blood pressure and diastolic blood pressure were also significantly increased 5) Urinary nitrogen and creatinine ratio known to be reliable index for nutritional status of protein was 5.5 : 1. These values were comparable to the values in American pregnant women. 6) The weight gain during the pregnancy was examined. There was little weight gain during the first trimester, because of nausea, vomit and decrease of appetite. The weight gain during the second trimester was 4.9Kg, and 11.1Kg for third trimester.

• Korean Journal of Community Nutrition
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• v.12 no.5
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• pp.545-558
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• 2007

This study was performed to assess the sodium intakes of Korean adults using a 24-hr urine analysis and dish frequency questionnaire (DFQ) according to each dish group and the regional area. The subjects of this study were comprised of 522 adults (male : 267, female : 285), aged 20-59yr residing in the metropolitan area (N=200), Chungcheng-Do (N=117), Jeolla-Do(N=117), and Gueongsang-Do provinces (N=118). The subjects were recruited from the residents who once participated or are participating in the various health programs offered by the public health center. The number of subjects who completed the 24-hr urine collection was 205 (male : 110, female : 95). The mean age and BMI of the subjects were $39.0{\pm}$11.7y and $23.1{\pm}2.9 kg/m^2$, respectively. The mean systolic and diastolic blood pressure was $119.5{\pm}15.4 mmHg$, and $77.1{\pm}11.1 mmHg$, respectively. Eighteen percent of the subjects responded that they are currently smoking, 36% drinking and 50.4% exercising. Twenty point six percent of the subjects were assessed as having hypertension according to their systolic or diastolic blood pressure($SBP{\ge}140mmHg$ or $DBP{\ge}90mmHg$) measurements in the present study. Salt intake of the subjects estimated with 24-hr sodium excretion was 12.7g/d (male : 13.4g/d, female : 12.1g/d) based on the sodium excretion rate as 82%. Salt intake estimated with DFQ was 14.7g/d (male : 16.2g/d, female : 13.4g/d), 2 g more than the salt intake estimated with 24-hr urine analysis. The four dish groups that contributed most to the sodium intake in order were kimchi (11571.4mg), soup and stew (1260.5mg), fish and shellfish(706.3mg) and noodle and ramyeon(644.3mg). Salt intake estimated with DFQ was the highest in the subjects of Gueongsang-Do(17.0g/d), second highest Chungcheong-Do (16.4g/d) and the lowest in the metropolitan area (13.0g/d). Subjects of Gueongsang-Do showed the highest sodium intakes in most of the dish group, whereas subjects of the metropolitan area showed the lowest. Residents of Chungcheong-Do revealed the highest sodium intake with kimchi and of Jeolla-Do the higher sodium intake with main dish (meat, fish and beans). The highest salt percentage of kimchi ($3.0{\pm}0.8%$) and soybean paste ($14.5{\pm}5.1%$) were observed in Gueongsang-Do, whereas individuals of the metropolitan area were observed as having kimchi ($1.6{\pm}0.5%$) and soybean paste ($7.4{\pm}1.6%$) with the lowest salt percenage. Men were observed as having more salty kimchi ($2.4{\pm}0.1%$) than women ($2.1{\pm}0.1%$).

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.269-279
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• 1984

The optimum conditions for measuring cadmium content of less than 0.2ppm by flame atomic absorption spectrophotometry were investigated. The cadmium in urine was extracted by APDC-MIBK for the analysis by atomic absorption spectrophotometry after ashing them by a wet method. 1. Optimum conditions by APDC-MIBK and DDTC-MIBK extractions. The acidic aqueous solution was prepared with appropriate amount of 0.IN nitric acid, 5ml of 25% (W/V) sodium potasstum tartarate, 10ml of saturated ammonium sulfate, and 2ml of 2% APDC(or 1 ml of 5% DDTC) chelating agent. The total volume of solution was adjusted to 55 ml and pH to $2{\sim}10$ (or$7{\sim}10$). The aqueous solution was extracted with 10ml MIBK. Concentration of Triton X-100 did not effect the absorbance for APDC-MIBK extraction of cadmium, but absorbance decreased as the concentration increased for DDTC-MIBK extraction. The sensitivity and detection limits for the cadmium determination from APDC-MIBK extraction were 0.0038ppm and 0.0102, 0.0022ppm and 0.0116 for DDTC-MIBK, and 0.0132ppm and 0.0034 for 0.1N nitric acid. APDC-MIBK and DDTC-MIBK extractions were 3 times higher than 0.1N nitric acid for the sensitivity. 2. Excretion of cadmium in 24-hour urine by APDC-MIBK extraction. Determination of cadmium in urine by atomic absorption spectrophotometry of A.A. (Cd=2 mA) mode and B.C. (Cd=4 mA) mode and B.C. (Cd=4mA, $D_2=20mA$) mode showed some difference (p<0.05). The difference of cadmium determination and recovery according to method of standard additions and standard calibration curve method in urine was not significant (p>0.05, $93.48{\pm}11.78%,\;94.83{\pm}22.00%$). Excretion of cadmium in 24-hour urine collection from normal person and variance analysis within measurement variation was not significant (p>0.05), but between interindividual was significant (0.05). Determination of cadmium content by two different methods of flame atomic absorption spectrophotometry and dithizone colorimetry showed that the results from the two methods can be described by a regression line with a good correlation (y=1.0153x-0.2927, x=Cd by D.C., y=Cd by A.A.S., $r=0.8651^*$, p<0.01).

• Childhood Kidney Diseases
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• v.2 no.2
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• pp.133-137
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• 1998

Purpose : To investigate renal toxicity of high-dose intravenous immunoglobulin(IVIG) in children with Kawasaki disease and idiopathic thrombocytopenic purpura. Methods : 23 children with Kawasaki disease and 7 children with idiopathic thrombocytopenic purpura who were treated with high-dose IVIG(2 g/kg) were evaluated for the change of urine output, blood urea nitrogen(BUN), serum creatinine(Scr), creatinine clearance(Ccr), tubular reabsorption of phosphorus(TRP), fractional excretion of sodium(FENa), 24hour urine ${\beta}_2$-microglobulin/creatinine(${\beta}_{2}MG/cr$) ratio and urine microalbumin/creatinine(MA/cr) ratio at post-IVIG 1 and 3 day. Results : There was no significant change of urine output, BUN, Scr, Ccr, TRP, 24hour urine ${\beta}_{2}MG/cr$ and MA/cr ratio after high-dose IVIG treatment. Transient increase of FENa at post-IVIG 1 day was the only significant change. Conclusion : There was no significant renal toxicity of high-dose IVIG in children with Kawasaki disease and idiopathic thrombocytopenic purpura who had normal renal function.

• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.27-32
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• 1991

We measured volume of daily urinary excretion. daily excretion of $Na^+$ and $K^+$, creatinine clearance, blood $Na^+$ and $K^+$ concentration on 34 subjects(12 men. 21 wenen) who live in Hanlim sub-county. Kimhae county. Kyongnam, Korea in December 1990. The data were compared to the data in 9 urban residents(4 men, 5 wemen). Results were as follows. I) Daily mean urinary $Na^+$ excretion of rural residents was $255{\pm}95.6$mEq/day. It is much lower than that of in 1960 but higher than that of students living in urban area(1975) or that of occidentals. 2) Daily mean urinary $K^+$ excretion of rural residents was $45{\pm}15.1$mEq/day. 3) $K^+$ excretion of rural residents was similar to that of urban residents but because of the relatively high $Na^+$ excretion, $K^+/Na^+$ ratio was significantly lower than that of urban residents. In conclusion. salt intake and excretion of rural residents tends to have been decreased progressively and it is thought to be the result of the improvement in dietary life especially increased intake of animal protein.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.168-177
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• 2007

Purpose : The purpose of this study was to investigate whether hypercalciuria patients with hematuria show different renal indices compared to non-hypercalciuria patients with hematuria. Methods : We retrospectively reviewed the medical records of patients with gross or microscopic hematuria whose blood chemistry and 24 hour urine chemistry were examined. After excluding the patients with more than $4 mg/m^2/day$ proteinuria or the patients with urinary calcium excretion between 3 and 4 mg/kg/day, we divided the patients into two groups: a hypercalciuria group whose calcium excretion was more than 4 mg/kg/day(n=30) and a non hypercalciuria group whose calcium excretion was less than 3 mg/kg/day(n=41). The urinary excretion, clearance, and fractional excretion(FE) of Na, K, Cl, Ca, P, urea, and creatinine were calculated and compared between the two groups. Results : The hypercalciuria group had more calcium excretion($6.1{\pm}2.9$ vs $1.5{\pm}0.9 mg/kg/day$), more urea excretion($341{\pm}102$ vs $233{\pm}123 mg/kg/day$), greater glomerular filtration rate(GFR) ($93.7{\pm}31.1$ vs $79.5{\pm}32.0 mL/min$) but lower FENa($1.0{\pm}0.4%$ vs $1.3{\pm}0.6%$) than the nonhyper-calciuria group, although the urinary sodium excretion was similar between the two groups. Conclusion : The greater urea excretion and GFR in hypercalciuric patients suggest that they might be on a higher protein diet than the non-hypercalciuria group. The increased glomerular filtration of sodium and calcium induced by the higher GFR in hypercalciuria would have increased their delivery to the distal tubule, where sodium is effectively reabsorbed but calcium is not, which is suggested by the lower FENa but higher FECa in hyercalciuria. It is recommended that the diet of hematuria patients be reviewed in detail at initial presentation and during treatment.

• Journal of Nutrition and Health
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• v.13 no.4
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• pp.187-194
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• 1980

To estimate the amount of daily salt intake by source of food and urinary sodium excretion, a dietary survey was conducted from August 27th to September 3, 1980. The salt concentration of six kinds of food was measured. The families of 25 womens' club leaders and 25 families of hypertensive patients were studied after they had been given a short course of education on lowsalt diet. The results were as follows: 1. The average amount of high-salt foods eaten daily by the study group were as follows: 4.5 Gm. in the form of table salt 16.8 ml of home-made soy sauce 6.20 ml of commercial soy sauce 11.9 Gm. of home-made red-pepper bean paste 12.0 Gm. of home-made soy-bean paste 120.7 Gm. of Kimchi 2. The average NaCl concentration of each food was as follows: 99.5% in table salt, 22.5% in home made soy sauce, 11.9% in Commercial soy sauce, 6.8 Gm% in home made red pepper bean paste, 9.2 Gm% in home-made soy-bean paste and the average concentration of various kinds of Kimchi was 2.7 Gm%. 3. The total amount of daily salt intake per adult was calculated as 14.3 Gm. By sources of food 4.5 Gm from table salt, 3.9 Gm from home-made soy sauce and 3. 3 Gm from Kimchi were taken daily Three other kinds of food were also minor sources of salt intake.4. The average amounts of individual daily salt intake were not significantly different between the hypertensive group and the normotensive group: the median of the normotensive group (11.7Gm.) was significantly lower than that of the hypertensive group (14.9Gm.). Therefore the womens' club leaders appeared to respond more quickly than the hypertensive group after low-salt diet education. 5. The average amount of sodium excretion in the 24 hour urine specimen was 234.7 mEq. From this finding the daily NaCl intake was estimated to be 15.8Gm.