Energy balance in children and young adultsreceiving haernodialysis for chronic renal failure

This study was designed to determine the contribution of energy expenditure tothe energy imbalance seen in uraemic children. Resting energy expenditure (REE) was measured using open-circuit indirect calorimetry in eight uraemic haemodialysed subjects aged 9.3–20.4 years and in 10 healthy children. Linear correlations between REE and both body weight and fat-free mass as measured by anthropometry were found in both controls and uraemic subjects (respectively: r = 0.76 and r = 0.88 for body weight and r = 0.73 and r = 0.90 for fat-free mass). Measured REE in uraemic patients was not different from the value predicted by using actual body weight and fat-free mass in the regression equation of REE on body weight and fat-free mass in controls (paired t test: p = 0.70 and p = 0.19 respectively). These data suggest that the energy imbalance seen in uraemic children is not due to increased energy expenditure and is therefore probably due to decreased food intake.     

Energy metabolism in acute and chronic renal failure

Energy metabolism was measured by indirect calorimetry in 86 patients with various forms of renal failure and in 24 control subjects. In patients with acute renal failure with sepsis, oxygen consumption, carbon dioxide production, and resting energy expenditure were increased (P less than 0.05). In other groups with renal failure (acute renal failure without sepsis, chronic renal failure with conservative treatment or hemodialysis, and severe untreated azotemia) these indices were not different from those of control subjects. Urea nitrogen appearance was decreased in patients with chronic renal failure undergoing conservative treatment, in those with severe untreated azotemia, and in hemodialysis patients (P less than 0.05). We conclude that renal failure has no influence on energy expenditure as long as septicemia is absent. Reduced urea nitrogen appearance rates in chronic renal failure are due to a reduced energy and protein intake. Wasting is a consequence of decreased food intake but not of hypermetabolism in chronic renal failure.     

Factors affecting the nutritional status of patients with chronic renal failure undergoing haemodialysis

There is a high prevalence of the features of protein-energy malnutrition among patients with chronic renal failure undergoing maintenance haemodialysis. Poor food intakes are only partly responsible. The disease state itself and renal replacement therapy are contributing factors to the development of malnutrition. Hypogeusia, anorexia and impaired digestion of nutrients have been reported. Changes in the hormonal environment may result in poor utilization and altered metabolism of nutrients. The requirements for nutrients may be different to those in normal healthy individuals. However, despite the effects of unalterable non-dietary factors on nutrition, it is possible to manipulate dietary intakes to improve the nutritional status.     

Taste perception of children with chronic renal failure

Taste sensitivity and preference in the suprathreshold ranges were compared for 20 pediatric patients with renal disease and 15 children with normal renal function. Nine patients had chronic renal insufficiency, and 11 had endstage renal disease. Subjects were also evaluated for various dietary, anthropometric, and biochemical parameters. All subjects were asked to pull out a tape measure to rate the strength of five varying concentrations of aqueous solutions of sucrose, sodium chloride, and quinine sulfate. The subjects' abilities to judge increasing concentrations with greater perceived intensity were measured by calculating individual and group slopes. No significant differences in the values were found between the groups. Similarly, no significant differences in mean peak preference concentrations were found between the groups. The patients with renal disease were found to be considerably growth retarded (height and weight less than 5th percentile), with a mean caloric intake less than 65% of the RDA even after an adjustment had been made for height. Serum zinc levels were all normal.     

The association of low birthweight and chronic renal failure among Medicaid young adults with diabetes and/or hypertension

OBJECTIVE: The purpose of this study was to assess the effect of low birthweight on chronic renal failure among young Medicaid patients with diabetes and/or hypertension. METHODS: The study included Caucasian and African American young adults, aged 18-50, who enrolled in the Medicaid program from 1993 to 1996 in South Carolina and were diagnosed with diabetes and/or hypertension. The odds of chronic renal failure by low birthweight (< 2,500 grams) was estimated using logistic regression. RESULTS: Of the 7,505 Medicaid patients with diabetes and/or hypertension, 179 (2.4%) were diagnosed with chronic renal failure. These patients were younger (mean age of 33.9 vs. 37.6, p = 0.0024) and had a higher proportion of low birthweight (15.1% vs. 11.4%, p = 0.07) compared with the 7,326 patients without renal failure. The odds ratio of chronic renal failure for low birthweight was significantly higher compared with normal birthweight (2,500-3,999 grams) (adjusted odds ratio [OR] 1.56, 95% confidence interval [95% CI] 1.0, 2.4). The association between low birthweight and chronic renal failure was stronger among the 888 patients with both diabetes and hypertension (OR 2.6, 95% Cl 1.3, 5.7) than the 1,812 diabetes or the 4,805 hypertension patients. CONCLUSIONS: The odds of chronic renal failure by low birthweight was highest in patients with both diabetes and hypertension, suggesting that the mechanism(s) involved in the disease progression to chronic renal failure may have a fetal early life origin.     

Elevated plasma vitamers of vitamin B6 in patients with chronic renal failure on regular haemodialysis.

Plasma pyridoxal-5'-phosphate (PL-5'-P), pyridoxal (PL), pyridoxine (PN), and 4-pyridoxic acid (4-PA) were measured by high-performance liquid chromatography (HPLC) in 39 patients (15 male, 24 female) with chronic fenal failure undergoing regular haemodialysis and 46 healthy controls (28 male, 18 female). All three vitamers of vitamin B6 and the metabolite were significantly elevated in the haemodialysis patients. Mean PL-5'-P and PN concentrations were 20 times the mean in controls. Only one patient took a vitamin B6 supplement. In view of the neurotoxicity of supranutritional intakes of PN in normal humans we suggest that supplements of PN be carefully monitored when administered to patients with chronic renal failure.     

Stroke in chronic renal failure

Chronic kidney diseases and cardiovascular diseases have several common risk factors like hypertension and diabetes. In chronic renal disease stroke risk is several times higher than in the average population. The combination of classical risk factors and those characteristic of chronic kidney disease might explain this increased risk. Among acute cerebrovascular diseases intracerebral hemorrhages are more frequent than in those with normal kidney function. The outcome of stroke is worse in chronic kidney disease. The treatment of stroke (thrombolysis, antiplatelet and anticoagulant treatment, statins, etc.) is an area of clinical research in this patient group. There are no reliable data on the application of thrombolysis in acute stroke in patients with chronic renal disease. Aspirin might be administered. Carefulness, individual considerations and lower doses might be appropriate when using other treatments. The condition of the kidney as well as other associated diseases should be considered during administration of antihypertensive and lipid lowering medications.     

瘦素与慢性肾衰

瘦素 (Ｌｅｐｔｉｎ)又称“抗肥胖激素” ,是近年来发现的一种存在于啮齿动物及人体的激素[1] 。由于它的生理功能与调节食物摄取及能量消耗有关 ,而慢性肾衰 (ＣＲＦ)病人常表现为厌食和蛋白营养不良。因此 ,它的发现受到肾脏病学家的高度重视[2 ] ,现对ＣＲＦ时瘦素水平的变化及其意义综述如下。一、瘦素的功能及其调节瘦素是肥胖基因的蛋白产物 ,它几乎完全由脂肪细胞分泌 ,通过血液循环 ,与靶器官受体结合 ,发挥生理功能。瘦素分子由 16 7个氨基酸组成 ,相对分子量 16 0 0 0 ,以游离及结合的形式存在于血浆中。在人类 ,瘦素的血浆浓度随…     

Trace element balance in adults receiving parenteral nutrition: preliminary data

There have been many recommendations regarding trace element needs of adults receiving total parenteral nutrition. Balance studies for zinc, copper, manganese, chromium, selenium, and molybdenum were carried out in 3 critically ill patients in an intensive care unit. Results indicate that the need for zinc was great in them, but that for copper and manganese was lower. Small negative chromium and selenium balances were observed. Molybdenum, iron, cobalt, and iodine balances were attempted but proved difficult to interpret. The requirement of each trace element varied from patient to patient, and was influenced by the presence of gastrointestinal fluid loss and renal function.     

Nutrition and HDL in children and young adults

Serum samples were collected from 7- and 8-year-old boys in 16 countries with different rates of coronary heart disease (CHD) mortality. Both serum total and high-density lipoprotein (HDL) cholesterols were lower in developing countries than in affluent countries. The mean of the HDL cholesterol/total cholesterol ratio varied within narrow limits: 0.24-0.27 in Asian countries, 0.30-0.36 in Africa, and 0.30-0.37 in the USA and Europe. Thus both total and HDL cholesterol increased under the influence of a more affluent diet. This conclusion is supported by results from controlled trials. Student volunteers received all their food from us for periods of 8 to 16 weeks. Diets were prepared from regular foodstuffs, in such a way that they differed in one nutrient only. Dietary composition was confirmed by double portion analysis. A moderate fat diet with a high P/S ratio was compared with a low-fat, low-PUFA diet and with two high-fat diets having a high or low P/S ratio. Both low-fat and high P/S diets effectively lowered total serum cholesterol. However, HDL was depressed by the low-fat diet in comparison with diets with a higher fat content, whether high or low in polyunsaturates. This difference in HDL persisted for at least 3 months. This suggests that "Western" diets, usually high in fat, elevate both total and HDL cholesterol concentrations in children and young adults.     

Comparison of two micronutrient supplements in children with chronic renal failure.

OBJECTIVE: To compare a newly formulated renal-specific micronutrient (RSM) supplement (vitamins C, E, K, and B complex, copper, zinc) with Ketovite (Paines & Byrnes, Middlesex, UK) tablets (vitamins C, E, K, and B complex) in children with chronic renal failure (glomerular filtration rate [GFR] < 25 mL/min/1.73 m(2)) or on chronic peritoneal dialysis (CPD) and hemodialysis (HD). DESIGN: Children currently prescribed Ketovite tablets were changed to RSM for 3 months. Questionnaires on palatability, acceptability, and ease of administration were assessed while on Ketovite and after 3 months on RSM along with plasma levels of zinc, copper, folate (serum, red cell), vitamin B(12), and homocysteine. SETTING: Regional pediatric nephrology unit. PATIENTS: Fifteen children (10 male) with a mean age of 10.4 years (range, 1.1 to 16 y) were recruited (11 had GFR < 25 mL/min/1.73 m(2), 2 CPD, 2 HD). Two children received overnight gastrostomy button feeding. Main Outcome Measures: Fourteen children (1 child refused RSM after 1 week) and their families completed questionnaires using a Likert scale: 1 (liked) to 7 (disliked). Plasma levels were analyzed at baseline on Ketovite and after 3 months on RSM. RESULTS: Children disliked the smell of Ketovite compared with RSM (P =.004). The size of Ketovite was preferable to the size of the RSM (P =.015) and was believed to be easier to administer (P =.046). There were no differences in patient/parent rating of appearance, texture, or taste, but 8 of 15 patients (53%) expressed a preference for the RSM if available. Plasma values of copper, zinc, folate, and vitamin B(12) were within the normal reference range on Ketovite and showed no significant change on RSM. Mean plasma homocysteine levels were above normal reference ranges in all groups (GFR < 25 mL/min/1.73 m(2), 7.6 [SD, 3.1]; CPD, 11.5 [SD, 1.6]; HD, 12 [SD, 8.7]) on Ketovite and were unchanged after 3 months on RSM. CONCLUSIONS: This pilot study confirms the acceptability of the RSM, particularly in relation to its smell and chewability, but the current size may preclude its widespread use. The incorporation of zinc and copper will be beneficial for many children, but reduction in homocysteine levels may necessitate an increase in folic acid content.