Adherence to the Mediterranean Diet Improves Fatty Acids Profile in Pediatric Patients with Idiopathic Nephrotic Syndrome

The fatty acid profiles of patients with idiopathic nephrotic syndrome (INS) are different from that of healthy controls, even during remission, revealing an increase of the pro-inflammatory omega 6 series. It is still unknown whether the concomitance of nephrotic syndrome affects the potential positive effects of the Mediterranean diet on the levels of omega 3 and 6 fatty acids. We performed a cross-sectional study to evaluate the association between the adherence to the Mediterranean diet and fatty acid profile in 54 children with INS. The dietary habits were assessed through the validated Kidmed questionnaire. Patients with higher adherence had lower levels of linoleic acid and total omega-6. Moreover, a negative correlation between proteinuria and the anti-inflammatory omega-3 series was found. In conclusion, patients with INS with proteinuria and low adherence to the Mediterranean diet have an imbalance in the omega-6/omega-3 ratio that may benefit from following the Mediterranean diet.

[Nutritional management of kidney diseases in children]

The prevalence of various kidney diseases in children remains high in recent decades. Adequate nutrition management can enhance the effectiveness of drug treatment, slow the frequency of relapses andprevent the progression of the disease. The article is devoted to modern approaches to diet therapy in various kidney diseases in children with the defeat of tubular and glomerular appa ratus. For the first time the therapeutic diets for children with various kidney diseases are presented. Particular attention is paid to diet therapy in nephrotic syndrome (steroid-responsive and steroid-refractory). Dietary approaches with modern formulas for enteral nutrition in cases of steroid therapy complications in children with renal insufficiency (in predialysis stage and on dialysis) are described. Differentiated nutritional approaches for patients with different types of crystalluria are separately presented.

[Nutrition of patients with stomach acid-dependent pathology and inflammatory diseases of the urogenital system]

In work some, often meeting nosological forms urogenithal surgical diseases which last years frequently proceed against gastritises, stomach ulcer of a stomach and 12-perstnoj guts owing to increase of occurrence of the last are presented. For treatment various medicamentous schemes, which do-polnjajutsja rational diet-correction for the purpose of increase efficaci and qualities of treatment are used. The work purpose--to present features ratsional pathogenetic correctic a food at persons from an aggravation acid-deprndent to a pathology against constant reception prepara apropos urogenithal diseases.

[Effectiveness of dietetic treatment in nephrotic syndrome]

We present the case of a male patient suffering from a primary amyloidosis and a nephrotic syndrome who came to dietotherapy clinic. In the first visit we made a nutritional record including an anthropometric evaluation, body composition, biochemistry, and food intake. The patient had an excess of body water, proteinuria, low plasma protein, albumin, prealbumin and HDL cholesterol levels, and high concentrations of total cholesterol, LDL and triglycerides. The consumption of protein and sodium was higher than the recommendation. An individualized diet was made. Six months later, his weight and the excess of body water decreased, but the fat free mass remained unchanged. The levels of albumin and prealbumin increased, the proteinuria decreased. Total cholesterol, LDL and triglycerides decreased until normal levels. Dietetary treatment in nephrotic syndrome is effective to decrease proteinuria, improve cholesterol and triglycerides levels, and to prevent malnutrition.

[Treatment of nephrotic syndrome in the adult]

Approximately two-third of the cases of the adult nephrotic syndrome is caused by a primary glomerular disease, while the remaining one-third is caused by diabetes mellitus, autoimmune diseases, or amyloidosis. There are two different therapies to treat the syndrome: a general and a special treatment. The general treatment includes administering an appropriate diet (reduced intake of proteins and salt), use of diuretics and lipid-lowering drugs (primarily statins) and initiation of anticoagulant treatment, if required. It is generally necessary to administer angiotensin-convertase-enzyme inhibitors and angiotensin receptor blockers as well as initiate a symptomatic treatment to mitigate the loss of special binding-proteins. The special treatment involves the administration of immunosuppressive and cytostatic drugs. This therapy can be initiated only after the evaluation of renal histology and the overall risk status of the patient. Steroids are still the basic immunosuppressive drugs. Their use can be supplemented with other immunosuppressive or cytostatic treatment. In therapy resistant cases, however, new drugs like mycophenolate mofetil or rituximab can also be applied.

Improved outcomes in nephrotic syndrome

Nephrotic syndrome can now be treated effectively in most cases. All patients should be treated with a low-salt diet, diuretics to reduce edema, and statins to normalize serum lipid concentrations. Patients with nephrotic syndrome are prone to deep vein thrombophlebitis, renal vein thrombosis, and pulmonary emboli. Depending on the condition, additional treatment may include corticosteroids, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), cyclosporine, cytotoxic agents, or mycophenolate.

CNP production in the kidney and effects of protein intake restriction in nephrotic syndrome

C-type natriuretic peptide (CNP) possesses well-established cardiovascular properties. Although present in the mammalian kidney, CNP production in human kidney and its modulation in human renal disease remain less defined. We investigated the presence of CNP in normal human kidney and in patients with nephrotic syndrome (NS). We also addressed whether or not a low-protein diet (LPD) alters plasma CNP and urinary CNP excretion in NS. In situ hybridization studies demonstrated CNP mRNA expression in tubular cells and glomeruli of normal human kidneys. CNP immunoreactivity was positive in proximal, distal, and medullary collecting duct tubular cells in both controls and patients with NS. The ratios of plasma CNP and urinary CNP to creatinine were significantly higher in patients with NS compared with controls. Urinary CNP, but not plasma CNP, was significantly lowered in patients with NS after an LPD. Similarly, the ratios of urinary protein to creatinine and urinary albumin to creatinine, but not urinary guanosine 3',5'-cyclic monophosphate to creatinine, decreased significantly with an LPD. These data confirm and extend previous reports and demonstrate for the first time the presence of CNP in human kidney with NS. We also report increased plasma CNP concentration and urinary CNP excretion in NS patients and a significant reduction of CNP excretion with an LPD. Our findings demonstrate that CNP metabolism is altered in patients with NS and support the hypothesis that activation of renal CNP can be partially offset by an LPD. These results underscore that the beneficial effect of an LPD on protein excretion is paralleled by a substantial reduction in intrarenal CNP release.

A soy protein diet alters hepatic lipid metabolism gene expression and reduces serum lipids and renal fibrogenic cytokines in rats with chronic nephrotic syndrome

Nephrotic syndrome (NS) is characterized by the presence of proteinuria and hyperlipidemia. However, ingestion of soy protein has a hypolipidemic effect. The present study was designed to determine whether the ingestion of a 20% soy protein diet regulates the expression of hepatic sterol regulatory element binding protein (SREBP)-1, fatty acid synthase (FAS), malic enzyme, beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA) reductase (r) and synthase (s), and LDL receptor (r), and to assess whether soy protein improves lipid and renal abnormalities in rats with chronic NS. Male Wistar rats were injected with vehicle or with puromycin aminonucleoside to induce NS and were fed either 20% casein or soy protein diets for 64 d. NS rats fed 20% soy protein had improved creatinine clearance and reduced proteinuria, hypercholesterolemia, hypertriglyceridemia, as well as VLDL-triglycerides and LDL cholesterol compared with NS rats fed the 20% casein diet. In addition, the soy protein diet decreased the incidence of glomerular sclerosis, and proinflammatory cytokines in kidney. Ingestion of the soy protein diet by control rats reduced the gene expression of SREBP-1, malic enzyme, FAS and increased HMG-CoAr, HMG-CoAs and LDLr. However, NS rats fed either casein or soy protein diets had low insulin concentrations with reductions in SREBP-1, FAS and malic enzyme expression compared with control rats fed the casein diet. NS rats fed the soy diet also had lower HMG-CoAr and LDLr mRNA levels than NS rats fed casein. In conclusion, the beneficial effects of soy protein on lipid metabolism are modulated in part by SREBP-1. However, in NS rats, the benefit may be through a direct effect of this protein on kidney rather than mediated by changes in expression of hepatic lipid metabolism genes.

Changes of protein kinetics in nephrotic patients

Nephrotic patients show various abnormalities in protein kinetics. Plasma albumin levels and the total plasma albumin pool are reduced. The rate of hepatic absolute and fractional albumin synthesis are increased. Transferrin synthesis is also increased. Fibrinogen levels are elevated in nephrotic syndrome because of an increase in the hepatic synthesis. Regulation of albumin and fibrinogen synthesis seems to be coordinated. A low protein diet has been proposed as a therapeutic tool in nephrotic patients--clinical studies have shown that such a diet reduces proteinuria and increases renal survival. Nephrotic patients can adapt to moderate protein restriction with no sign of malnutrition and maintenance of a neutral nitrogen balance. Albumin and fibrinogen synthesis are ameliorated by dietary protein restriction and these changes are correlated with the beneficial effect of the diet on proteinuria.

Effects of dietary protein restriction on fibrinogen and albumin metabolism in nephrotic patients

BACKGROUND

Nephrotic syndrome (NS) is characterized by profound changes in albumin and fibrinogen levels. Dietary protein restriction has been advocated in the treatment of patients with NS, but its effects on albumin and fibrinogen metabolism have not been fully elucidated.

METHODS

We evaluated the effects of dietary protein restriction on endogenous leucine flux (ELF), fibrinogen and albumin metabolism in seven patients with NS who consumed either a normal protein diet (NPD; 1.20 +/- 0.06 g/kg/day), or a low protein diet (LPS; 0.66 +/- 0.04 g/kg/day) for four weeks. Seven normal subjects served as controls. The postabsorptive ELF value, fractional synthesis rate (FSR) and absolute synthesis rate (ASR) of both albumin and fibrinogen were evaluated during the last 120 minutes of a five-hour 5,5,5-D3-L-leucine infusion.

RESULTS

During the NPD regimen. ELF was increased, serum albumin was reduced, plasma fibrinogen was increased, albumin FSR and ASR were both increased, fibrinogen FSR was normal, and fibrinogen ASR was greater in patients with NS compared to controls. In patients with NS the LPD regimen reduced proteinuria, ELF, albumin FSR and ASR, plasma fibrinogen levels, fibrinogen ASR, and increased serum ulbumin levels. Dietary-induced changes in albumin and fibrinogen synthesis were significantly correlated (r = 0.719, P < 0.05).

CONCLUSIONS

Patients with NS treated with LPD show: (1) a reduction of proteinuria, albumin ASR and FSR, with an increase in serum albumin levels and its intravascular pool; (2) a decrease of fibrinogen ASR, with a reduction in both plasma fibrinogen levels and intravascular pool; and (3) a reduced rate of whole body proteolysis.

[Dietary antioxidants and total antioxidant status in children with nephrotic syndrome]

Several studies indicate the pathophysiological importance of reactive oxygen species in patients with nephrotic syndrome (NS). The present study was designed to determine the effect of dietary antioxidants on antioxidant enzymes (SOD, GPX, GR) activity and on total antioxidant status (TAS) in children with nephrotic syndrome. 36 children with NS (19 with first episode and 17 with relapse of NS) aged 4-16 were included into the study. Total antioxidant status was estimated using two-reagent Randox Total Antioxidant Status test in plasma. All patients had normal blood pressure, normal serum creatinine level and ingested a diet appropriate for age (with individual differences). Total antioxidant status was estimated using two-reagent Randox Total Antioxidant Status test in the plasma. Glutathione peroxidase (GPX), superperoxide dysmutase (SOD) and glutathione reductase (GR) activity was using antioxidant kits (Randox). A 3-day dietary intake record was obtained from each patient and then analyzed with computer program FOOD 2.0. Laboratory investigations were performed before steroid treatment.

RESULTS

1) in children with NS TAS was significantly reduced comparing to controls (0.84 +/- 0.14, 1.21 +/- 0.62 mmol/l, p = 0.002), 2) low manganese intake was found to have negative influence on TAS (TAS = 0.38 + 14.252*Mn, p > 0.001). 3) low intake of all components of antioxidant system was found: zinc (5.6 +/- 3.5 mg/kg b.w./24 h vs 8.6 +/- 4.0 mg/kg b.w./24 h), copper (0.021 +/- 0.013 mg/kg b.w./24 h vs 0.044 +/- 0.014 mg/kg b.w./24 h), manganese (0.029 +/- 0.0021 mg/kg b.w./24 h vs. 0.067 +/- 0.023 mg/kg b.w./24 h), vitamin E (0.15 +/- 0.04 mg/kg b.w./24 h vs 0.26 +/- 0.06 mg/kg b.w./24 h) and vitamin C (0.34 +/- 0.17 mg/kg b.w./24 h vs 0.87 +/- 0.19 mg/kg b.w./24 h).

CONCLUSION

In children with NS reduced antioxidant protection maybe partly associated with low intake of some vital components of the antioxidant system.

Mechanisms permitting nephrotic patients to achieve nitrogen equilibrium with a protein-restricted diet

Clinical experience suggests nephrotic patients are at risk for malnutrition. To determine if nephrotic patients can adapt successfully to a protein-restricted diet, nephrotic (glomerular filtration rate, 52+/-15 ml/min; urinary protein [Uprot.], 7.2+/-2.2 grams/d) and control subjects completed a crossover comparison of diets providing 0.8 or 1.6 grams protein (plus 1 gram protein/gram Uprot.) and 35 kcal per kg per day. Nitrogen balance (BN) was determined and whole body protein turnover measured during fasting and feeding using intravenous -[1-13C]leucine and intragastric -[5,5, 5- 2H3]leucine. BN was positive in both nephrotic and control subjects consuming either diet and rates of whole-body protein synthesis, protein degradation, and leucine oxidation did not differ between groups. In both nephrotic and control subjects anabolism was due to a suppression of whole-body protein degradation and stimulation of protein synthesis during feeding. The principal compensatory response to dietary protein restriction was a decrease in amino acid oxidation and this response was the same in both groups. With the low protein diet leucine oxidation rates during feeding correlated inversely with Uprot. losses (r = -0.83; P < 0. 05).

CONCLUSIONS

(a) a diet providing 0.8 gram protein (plus 1 gram protein/gram Uprot.) and 35 kcal per kg per day maintains BN in nephrotic patients; (b) nephrotic patients activate normal anabolic responses to dietary protein restriction (suppression of amino acid oxidation) and feeding (stimulation of protein synthesis and inhibition of protein degradation); (c) the inverse correlation between leucine oxidation and Uprot. losses suggests that proteinuria is a stimulus to conserve dietary essential amino acids.

Treatment of nephrotic adults with a supplemented, very low-protein diet

Optimal dietary protein intake for adults with the nephrotic syndrome has not been established; very low-protein diets are believed to be contraindicated. Sixteen patients with the nephrotic syndrome were nevertheless prescribed a very low protein diet (0.3 g/kg) supplemented by 10 to 20 g/d essential amino acids (or, in a few cases, ketoacids) for an average of 10 months (range, 1 to 36 months). In 11 patients with initial glomerular filtration rates (GFRs) < or = 30 mL/min/3 m2 of height (ht)2, significant but modest improvement was seen (on the average) in proteinuria, serum albumin, and serum cholesterol; all 11 eventually went on to dialysis. The other five patients, with initial GFRs of 32 to 69 ml/min/3 m2 of ht2, had either focal segmental glomerulosclerosis, diabetic nephropathy, or, in one patient, both. The nephrotic syndrome associated with these disorders rarely remits spontaneously. However, during the following 3 to 15 months mean proteinuria decreased from 9.3 to 1.9 g/d, mean serum albumin increased from 2.5 g/dL to 3.8 g/dL, and mean serum cholesterol decreased from 415 mg/dL to 255 mg/dL (all P < 0.001). The GFR either remained constant or increased. Four of these five patients have resumed normal or nearly normal diets and remain in remission or near-remission for 6 to 24 months. We conclude that severe protein restriction plus an essential amino acid supplement may induce prolonged remission in adults with the nephrotic syndrome provided that GFR is not severely reduced. The mechanism of this paradoxical response to protein restriction remains to be determined.

Renal effects of captopril, indomethacin and nifedipine in nephrotic patients after an oral protein load

BACKGROUND

In this study we investigated whether the increase in proteinuria induced by an oral protein load may be prevented by the angiotensin-converting enzyme inhibitor (ACEI) captopril in patients with nephrotic syndrome, and whether the effects of captopril on renal haemodynamics and/or glomerular selectivity are comparable to those obtained with the nonsteroidal anti-inflammatory drug (NSAID) indomethacin and the calcium-channel blocker (CaCB) nifedipine.

METHODS

Twelve subjects underwent the following treatments: (1) low-protein meal (0.2 g protein/kg body wt), (2) high-protein meal (1.3 g protein/kg body wt), (3) high-protein meal plus oral captopril (50 mg), (4) high-protein meal plus oral nifedipine (10 mg), (5) high-protein meal plus oral indomethacin (50 mg). Urine and blood samples were obtained after meals and tested for total protein, immunoglobulin G and albumin. GFR and renal plasma flow (RPF) were calculated from iothalamate and p-aminohippuric acid clearances respectively.

RESULTS

Mean arterial pressure decreased significantly after both captopril (-4%, P = 0.001) and nifedipine (-5%, P = 0.0019). Compared with the low-protein meal, mean values of GFR and RPF increased significantly after the high-protein meal alone (+21%, P = 0.0002; +10%, P = 0.0491 respectively), and after captopril (+18%, P = 0.0025; +24%, P = 0.0034 respectively) or nifedipine administration (+30%, P = 0.0001; +21%, P = 0.0036 respectively), whereas they remained unchanged after the high-protein meal plus indomethacin administration. FF did not change significantly under the five experimental conditions. The increase in urinary protein excretion induced by the meat load (total protein +18%, P = 0.0102; albumin +26%, P = 0.0316; IgG +28%, P = 0.0203) was entirely blocked by both captopril and indomethacin, whereas it was further increased by nifedipine administration.

CONCLUSIONS

Both captopril and indomethacin, but not nifedipine, are able to prevent the increase in urinary protein excretion rate following a meat meal. The antiproteinuric effect of captopril is comparable to that of indomethacin, but the renal haemodynamic changes induced by these drugs differ considerably, because the filtration capacity and the renal functional reserve were preserved by captopril and decreased by indomethacin. The reduction in systemic blood pressure following administration of both captopril and nifedipine does not account for changes in proteinuria, since, with a similar degree of blood pressure lowering, urinary protein excretion is reduced by captopril and increased by nifedipine.

Nutritional therapy for progressive renal failure

Results of the Diabetes Control and Complications Trial indicate that intensive insulin treatment of patients with type I diabetes would greatly reduce the incidence of diabetic nephropathy. Another multicenter trial indicates that modest protein restriction is of no value in children with chronic renal failure. The relationship between urea nitrogen excretion and total nitrogen excretion in children differs from that in adults. A repeated crossover study found that ketoacids slow progression of renal failure, in comparison with amino acid supplements to the same diet. Long-term protein restriction does not lead to protein deficiency at the onset of dialysis. When combined with essential amino acid supplements, a low-protein diet may gradually correct hypoalbuminemia in nephrotic subjects.

Treatment of proteinuric patients with a vegetarian soy diet and fish oil

Our aim was to determine whether a longer period of treatment with a vegetarian soy diet with addition of fish oil supplements would accentuate the beneficial effects on hyperlipidemia and proteinuria of nephrotic patients we found in a previous study. After an 8-week baseline period on free diet, patients were randomly allocated either on soy diet alone (SD) or to SD plus 5 g/day of fish oil (SD + FO) orally for two months. Then they crossed over to the other treatment for two additional months. They finally resumed eating the free diet for 3 months. We selected 20 outpatients with chronic glomerulonephritis, proteinuria in the nephrotic range, fasting serum cholesterol > 250 mg/dl, mean serum creatinine concentrations 1.75 +/- 0.23 mg/dl. Serum lipid profile, urinary protein loss and nutritional parameters were monitored. With the soy diet, we obtained a significant decrease both of hyperlipidemia and of proteinuria. The effect of the soy diet on proteinuria increased over the 4 months. The addition of a moderate amount (5 g/day) of fish oil in a randomized cross-over design had no further beneficial effect. Stability of serum albumin, transferrin and the body mass index documented good nutritional status. In conclusion, the dietary manipulation with our vegetarian soy diet confirmed the beneficial effects on hyperlipidemia and proteinuria of nephrotic patients. Such effects persisted and even ameliorated after 4 months of diet. The addition of moderate oral supplements of fish oil did not potentiate the beneficial effect.

Influence of diet on lipid abnormalities in human renal disease

The scarce literature on dietary manipulation of dyslipidemia in patients with nephrotic syndrome and in patients with chronic renal insufficiency is reviewed. Our favorable personal experience in both clinical conditions is illustrated as well. A special low-protein soy diet given for 2 or 4 months partially corrected hypercholesterolemia in nephrotic patients, and a low-protein diet also low in cholesterol and rich in polyunsaturated fatty acids corrected hypertriglyceridemia and hypercholesterolemia in patients with progressive renal damage. The soy diet had an additional favorable effect on proteinuria of nephrotic patients that might have been a direct consequence of the partial correction of the hypercholesterolemia. The addition of 5 g/d of fish oil to the soy diet did not modify the effects of the soy diet on proteinuria nor was it able to correct the hypertriglyceridemia of nephrotic patients. Dietary intervention should be the first-line treatment for the dyslipidemia of these renal diseases, since it can be used for long periods of time and is devoid of side effects so long as good nutritional status is maintained.

Diet as culprit or therapy. Stone disease, chronic renal failure, and nephrotic syndrome

A number of renal disorders are amenable to dietary manipulation. This article reviews nutritional strategies for the management of renal stone disease, chronic renal failure, and nephrotic syndrome. The first portion discusses dietary factors that promote urolithiasis and dietary recommendations utilized in the medical management of stone disease. The second segment discusses the pathophysiology of the progression of renal disease and nutritional interventions to delay progression. Finally, the third portion examines losses of protein, vitamins, and minerals in the nephrotic syndrome and makes recommendations for replacement.

Vegetarian diets for treating nephrotic syndrome

Vegetarian diets based on soy-protein appeared to be effective in treating the hyperlipidemia of nephrotic syndrome. Whether there is a unique effect of soy or whether all very low-fat, low-saturated-fat, low-cholesterol, and low-protein diets have similar effects remains unknown.

Hormonal modulation of proteinuria in the nephrotic syndrome

Proteinuria is the primary manifestation of a variety of glomerular diseases which are characterized clinically by the nephrotic syndrome. In many cases there is little effective treatment for the primary disease process. However, reduction of proteinuria can frequently improve the hypoalbuminemia, hyperlipidemia and edema which are responsible for the morbidity of the nephrotic syndrome. Proteinuria can be reduced in nephrotic humans and experimental animal models by restriction of dietary protein intake, nonsteroidal anti-inflammatory drug, and by angiotensin-converting enzyme inhibitors. Each of these therapies modifies the activity of locally acting glomerular hormones, autocoids, suggesting that there is a component of proteinuria which is hormonally mediated. The effects of dietary protein, nonsteroidal anti-inflammatory drugs, and angiotensin-converting enzyme inhibitors on nephrotic proteinuria and their potential hormonal mechanisms of action is the subject of this review.

Relationship between hyperlipidemia, lipid mediators, and progressive glomerulosclerosis in the nephrotic syndrome

Nephrotic syndrome is defined by proteinuria, hypoalbuminemia, edema and hypercholesterolemia. Evidence from both the experimental and clinical literature suggests that high lipid levels are not only a marker of disease, but also contribute to the process of glomerulosclerosis. Lipid mediators, including eicosanoids, platelet-activating factor, and chemotactic factors, can contribute by effecting leukocyte infiltration, mesangial proliferation, extracellular matrix protein production, vasoreactivity, and coagulation. Infiltrating macrophages may play a central role in these processes. Therapeutic maneuvers aimed at the correction of lipid abnormalities may halt or slow the progression of nephrotic syndrome to end-stage renal disease.

Omega-3 fatty acid supplementation in primary nephrotic syndrome: effects on plasma lipids and coagulopathy

The effect of fish oil dietary supplementation on the dyslipidemia and coagulopathy of seven patients with nephrotic syndrome and hypoalbuminemia due to primary kidney disease was studied. Plasma lipids, platelet aggregation studies, simplate bleeding time, and fibrinogen levels were determined before and after 6 wk of treatment with fish oil (15 g/day of MaxEPA; 2.7 g of eicosapentenoic acid (EPA) and 1.8 g of docosahexenoic acid. Urea kinetics were determined from urine-urea concentration, urinary proteina, and urine volume. A 3-day dietary intake record was obtained from each patient before and after 6 wk of fish oil supplementation. There was no significant dietary change in protein, fat, or carbohydrate intake over the time period of the study. At study end, total triglycerides decreased from 2.98 +/- 1.31 to 2.18 +/- 1.14 mmol/L (P = 0.002), and very low-density lipoprotein-triglycerides decreased from 2.35 +/- 1.34 to 1.28 +/- 1.07 mmol/L (P = 0.01). Low-density lipoprotein (LDL) cholesterol increased from 5.18 +/- 1.74 to 7.35 +/- 2.83 mmol/L (P = 0.005). No significant changes occurred in bleeding time, platelet count, hematocrit, red blood cell flexibility, or whole blood viscosity. Platelet aggregation responses to collagen and arachidonic acid were consistently reduced after treatment, but there was no change in platelet response to ADP. The platelet membrane phospolipids showed a significantly increased incorporation of EPA after the fish oil diet (P = 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Growth, serum lipoproteins and apoproteins in infants with congenital nephrosis

Retarded growth and extremely high cholesterol levels have been reported in infants with congenital nephrotic syndrome of the Finnish type (CNF). In an attempt to normalize growth and lipid disturbances the high-calorie diet (130 kcal/kg/d) containing protein 4 g/kg/d and supplemented with unsaturated fatty acids (mean P/S-ratio 1.40) was given to ten infants with CNF from birth. Growth, lipoprotein and apoprotein concentrations were measured. All patients exhibited normal growth, which allows renal transplantation, the only life-saving treatment in CNF, already at an early age. In spite of the diet lipid profiles at 3 and 9 months revealed marked elevation of triglyceride in all lipoproteins, especially in VLDL fraction, compared to controls. The abnormalities increased significantly with time (p for VLDL-TG 0.04). The elevation of serum cholesterol was mainly attributable to the increase of cholesterol in triglyceride-rich particles (chylomicrons, VLDL, IDL). Analysis of VLDL, LDL and HDL revealed significant triglyceride enrichment and cholesterol deficiency in all lipoproteins. The concentrations of the low-molecular weight apoproteins A-I and A-II were significantly decreased, but the concentration of high-molecular apo B was high. Urinary analysis revealed progression and decreasing selectivity of proteinuria with time. Thus the mechanisms leading to lipid abnormalities in CNF are multiple including stimulated hepatic lipoprotein synthesis, impaired conversion of VLDL and IDL to LDL, compositional changes, urinary loss of low-molecular apoproteins and presumably reduced LPL activity. The abnormalities indicate an increased risk of arteriosclerosis in CNF patients.

[Steroid-resistant nephrotic syndrome in 2 children with milk protein intolerance]

Two cases of steroid-resistant nephrotic syndrome with mesangial proliferation were observed in which prednisone treatment resulted in remission only after milk-free diet. In both children intolerance to cow milk protein was demonstrated, and in one of them a family history of this intolerance was elicited.

Ineffectiveness of dietary protein augmentation in the management of the nephrotic syndrome

The nephrotic syndrome is a consequence of altered permselectivity of the glomerular basement membrane resulting in urinary losses of albumin and other serum proteins. Although dietary protein augmentation increases albumin synthesis, it has not been shown to increase serum albumin or muscle protein. Dietary protein was increased from 8.5% to 21% in pair-fed rats with Heymann nephritis and resulted in an increase both in albumin synthesis and urinary albumin excretion, but not in serum albumin concentration or in total albumin pools. The increase in dietary protein was 8 times greater than the resulting increase in urinary protein excretion, but nearly all of the additional ingested protein was catabolized to urea and excreted in the urine rather than used to augment growth. Dietary supplementation with protein has no obvious beneficial effect on nutritional status of nephrotic rats.

Effect of dietary proteins and lipids in patients with membranous nephropathy and nephrotic syndrome

Twenty-four patients with idiopathic membranous nephropathy, long-lasting nephrotic syndrome and serum creatinine less than 2 mg/dl ate sequentially, in a randomized cross-over design, a normal protein diet containing 1.1 +/- 0.3 g/kg/day of proteins and a low protein diet containing 0.7 +/- 0.1 g/kg/day of protein, each diet for a period of 3 months. Both diets were low in fat (less than 30% of total calories) and cholesterol (less than 200 mg/day) content and rich in polyunsaturated fatty acids and in linoleic acid (10% of energy). Random assignment to one of the two 3 month diet periods was done after a RUN-IN period of at least one month on the hypolipidic normal protein diet. Glomerular filtration rate (inulin clearance), 24 hour urinary protein loss and serum albumin concentration did not significantly differ at the end of the two diet periods, indicating that long-term restriction of protein intake does not modify GFR or urinary protein loss in nephrotic patients. Serum total and LDL-cholesterol and daily proteinuria were significantly lower at the end of both diet periods than at the beginning and at the end of the RUN-IN period. We suggest that these changes were a consequence of the manipulation of dietary fat intake.

A special, supplemented 'vegan' diet for nephrotic patients

High dietary protein intake, in the past recommended for nephrotic syndrome, does not improve hypoproteinemia and may accelerate progressive renal damage. In contrast, low-protein diets reduce proteinuria and preserve renal function in experimental renal models of nephrotic syndrome. In this study, 20 steroid-resistant, nephrotic patients were treated with a pure vegetarian, low-protein diet, supplemented with essential amino acids and ketoanalogues (supplemented vegan diet, SVD) for 4.6 +/- 3.1 months. Before the study, these patients followed an unrestricted protein, low-sodium diet (LSD). Proteinuria, daily urea nitrogen excretion and creatinine clearance decreased significantly on SVD. A similar lowering effect of SVD was observed on serum total cholesterol. Seven of the 20 patients changed from LSD to SVD and vice-versa on 3 occasions, and in all cases, we found an increase of proteinuria during the LSD period. Serum albumin, HDL cholesterol, triglycerides and anthropometric measurements did not change on SVD. Our data suggest that SVD exerts a favorable effect on proteinuria and hypercholesterolemia in nephrotic patients, without inducing clinical or laboratory signs of malnutrition.

Low protein supplemented diet corrects altered serum thyroid hormone and TSH concentrations in patients with chronic nephrotic syndrome

Creatinine clearance, daily urinary protein excretion, serum concentrations of thyroid hormones (TT4, TT3, fT4, fT3), TSH and parathyroid hormone (PTH), have been measured before and after 2 or 6 months of a low protein diet supplemented with aminoacids and ketoanalogues in 18 patients affected by chronic nephrotic syndrome without significant impairment of renal function. Mean creatinine clearance and mean serum protein concentration (79.5 +/- 13.8 ml/min and 5.4 +/- 0.6 g/dl, mean +/- S.D., respectively) did not significantly change (79.1 +/- 17.3 ml/min and 5.5 +/- 0.6 g/dl) after the diet. Mean daily urinary protein excretion (7.1 +/- 2.2 g/day basally) significantly decreased (5.5 +/- 1.9 g/day) after the diet (p less than 0.05). Mean serum TT4 concentration (5.6 +/- 1.8 micrograms/dl basally) significantly increased (6.7 +/- 2 micrograms/dl, p less than 0.05) after the diet. Mean serum TT3 concentration (106.7 +/- 28.5 ng/dl, basally) significantly increased (126.7 +/- 22.6 ng/dl) after the diet (p less than 0.01). Mean serum fT4 and fT3 concentrations (8.0 +/- 2.9 pg/ml and 4.5 +/- 1.6 pg/ml, respectively) did not significantly change (9.4 +/- 2.7 pg/ml, and 4.9 +/- 1.9 pg/ml, respectively) after the diet. In some patients low basal serum concentration values of TT4, TT3, fT4, fT3 became normal after the diet. Mean serum TSH concentration (3.1 +/- 2.3 microU/ml basally), significantly decreased (1.5 +/- 1.3 microU/ml) after the diet (p less than 0.05). Mean serum PTH concentration (0.7 +/- 0.3 ng/ml basally) significantly decreased (0.4 +/- 0.2 ng/ml) after the diet (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

[Idiopathic nephrotic syndrome. Effect of oral cromoglycate]

The occurrence of idiopathic nephrotic syndrome may be due to environmental antigens, and in particular to the ingestion of certain foods, as indicated by the result of food eviction tests. This led us to prescribe oral cromoglycate (800 mg/day for 2 weeks) combined with the avoidance of specific foods. Twelve patients with corticosteroid-dependent (n = 6) or corticosteroid-resistant (n = 6) idiopathic nephrotic syndrome with proteinuria greater than 1.50 g/24 h were thus treated without modification of steroid dosage. In 3 of these patients hypersensitivity to certain foods had previously been demonstrated. In 5 of the 12 patients, proteinuria was reduced by more than 50 percent; these 5 patients had received cromoglycate for 2 weeks with a free diet. After evictions were stopped, 3 patients relapsed; in 2 cases proteinuria remained absent. In 3 of the 12 cases, we subsequently used cromoglycate and evictions in corticosteroid-dependent patients in complete remission by gradual reduction of steroid dosage in the hope of lowering the dependence threshold. In one patient, the corticosteroid therapy could be discontinued during 3 months without relapse; in the other 2 patients no effect was observed. Thus, oral cromoglycate could be used together with food eviction in certain cases of idiopathic nephrotic syndrome, this being a therapeutic approach as well as a diagnostic test.

Vegan supplemented diet in nephrotic syndrome

Thirteen patients (7 males, 6 females, aged 17-68 years) affected by primary, steroid-resistant, nephrotic syndrome and normal renal function were treated with a vegan, low-protein (0.7 g/kg per day) diet supplemented with essential amino acids and Ketoanalogues (VSD) for 3.9 +/- 2.9 months. These patients were studied at the beginning (following an unrestricted protein diet (UPD) supplying about 1 g/kg per day of mixed proteins) and at the end of VSD period. Urinary protein excretion decreased from 8.7 +/- 2.6 to 5.6 +/- 2.4 g/day (P less than 0.01), serum total cholesterol from 334.6 +/- 97.1 to 275.6 +/- 49.4 mg/dl (P less than 0.05). Serum albumin, HDL-cholesterol, triglycerides, and anthropometric measurements (triceps skinfold thickness and middle arm muscle circumference) did not change. Urinary urea nitrogen decreased from 7.5 +/- 1.8 to 3.8 +/- 1.2 g/day (P less than 0.005), according to dietary prescriptions. Creatinine clearance changed from 104.4 +/- 28.7 to 89.3 +/- 16.7 ml/min (n.s.) and no correlation was found with the changes in urinary protein excretion. This data suggest that VSD reduces proteinuria and exerts favourable effects on hypercholesterolaemia. Protein malnutrition was absent in these patients, probably because of the essential amino acids and ketoanalogues supplementation.

Food allergy and idiopathic nephrotic syndrome

Patients with the idiopathic nephrotic syndrome (INS) with steroid treatment failure, who did or did not have a history suggesting food intolerance, were systematically evaluated for food allergy. We evaluated 42 cases for sensitization to usual foods. The following results were obtained: skin tests (intradermal, Stallergenes Lab) were positive in 16 out of 42 cases; total serum IgE was elevated in 12 of 42 patients; specific IgE (RAST) was positive in eight of 42 patients; the basophil histamine release test (HRT) was positive in 20 of 42 patients. For each of these tests, the results in the INS patients with steroid treatment failure were significantly different from controls. The following exclusion or challenge tests were carried out. In seven cases, an elemental diet was used; proteinuria decreased in one case, but acceptance of the diet was poor in the other cases. In 27 cases, a limited diet with exclusion of one or several foods was used. A complete remission was induced by this diet in seven steroid-dependent INS cases, allowing steroids to be discontinued during a follow-up of one to five years. However, relapses were frequent. More recently, an oligoantigenic diet was prescribed for 10 days without modifying steroid therapy. In 13 INS patients (5 steroid-dependent, 3 steroid-resistant, and 5 multiple relapses), 24-hour urine protein was significantly reduced (P less than 0.05). Proteinuria decreased by more than half in nine patients, with complete disappearance in five cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary manipulation for idiopathic nephrotic syndrome. A new approach to therapy

To evaluate the role of food antigens in idiopathic nephrotic syndromes, we used dietary manipulations in 26 cases in whom steroid therapy had failed. In the six reported, restricted diets according to clinical and biological data were followed by complete remissions, suggesting that food can be responsible for idiopathic nephrotic syndrome in selected cases, and leading to a new therapeutic approach. The mechanism by which such antigens can be implicated in the pathogenesis of this glomerular disease is discussed.

Effect of a high protein diet in patients with the nephrotic syndrome

1. Twelve patients with the nephrotic syndrome were prescribed for 4 week periods a normal protein diet (NPD) containing 1 g of protein/kg ideal body weight. They were then prescribed for further 4 week periods in random order diets with high (HPD) and low (LPD) protein contents, respectively 2.0 and 0.5 g/kg ideal body weight. 2. Compliance was confirmed by dietary history and measurement of urinary excretion. 3. Serum albumin was the same on all diets. Twenty-four hour urinary protein excretion increased progressively with increasing dietary protein (LPD 6.1 g. NPD 8.2 g. HPD 9.2 g). Recumbent plasma renin activity and serum phosphate were significantly increased on HPD (plasma renin activity: LPD 5.7, NPD 4.6, HPD 8.2 pmol of angiotensin I min-1 1(-1); serum phosphate: LPD 1.27, NPD 1.26, HPD 1.41 mmol/l). 4. There was no evidence of protein-induced hyperfiltration or hyperperfusion: 51Cr-ethylenediaminetetra-acetate and [125I]iodohippurate clearances were similar on all three diets. 5. Since proteinuria, increased plasma renin levels and hyperphosphataemia may contribute to progression of renal failure and because HPD did not improve hypoalbuminaemia, the use of HPD in the nephrotic syndrome should be abandoned. 6. Until it can be established that LPD, which is accompanied by the least proteinuria, does not, with long-term feeding, lead to malnutrition, NPD should be used in the treatment of the nephrotic syndrome.

[Idiopathic nephrotic syndrome and food hypersensitivity. Value of an exclusion diet]

A case of idiopathic nephrotic syndrome (INS) evolving since more than 7 years with 4 successive corticosensitive relapses is reported. At the time of a 5th relapse corticosteroid treatment was refused by the parents and evolution went on without any spontaneous tendency to remission. Three months later, allergy tests detected various sensitizations, especially for food allergens. An antiallergic treatment including dietary exclusions induced a complete and durable remission. Five similar cases are reported. These facts, compared to data from the literature, indicate the possible role of food hypersensitivity in INS. Its mechanism has been discussed; the possible part of a lymphocyte activation has been emphasized.

[Phosphorus-calcium metabolism and dietetic correction of its disorders in chronic kidney diseases in children]

Ninety children with varying renal diseases were under observation. The investigations conducted have shown that disorders in phosphoric-calcium metabolism depend on the type, activity of chronic glomerulonephritis (CGN) and etiology of chronic renal insufficiency (CRI). Significant disorders in phosphoric-calcium metabolism were detected in patients with nephrotic and mixed types of CGN. Most manifest clinical and x-ray changes of the osseous system were observed in patients with CRI that developed as a result of the tubulointerstitial pathologic process. Low-phosphate diets with preset amounts of Ca and P were developed, composed of products with relatively low content of P, and of new dietetic products rich in Ca. The diets were used for correction of hyperphosphatemia in children with CGN and in those with CRI, simultaneously with drug therapy, to prevent or diminish disorders in phosphoric-calcium metabolism, and to reduce the risk of invalidism among children with chronic renal diseases.

Dietary fat in experimental nephrotic syndrome: beneficial effects of fish oil on serum lipids and, indirectly, on the kidney

Three isocaloric diets with different fat composition were fed to rats for seven weeks after the production of nephrotic syndrome by adriamycin. The effects of feeding 3% and 14% fish oil were compared with those of feeding beef fat. At the fourth week of feeding the levels of triglycerides and cholesterol were lower in both fish oil fed groups. At the seventh week these levels, and the LDL cholesterol, were lower only in the 14% fish oil group. In rats fed beef fat, but not in those fed fish oil, there was a striking positive correlation of the four-week serum triglycerides and cholesterol with the seven-week serum creatinine level and with the degree of glomerular hyalinosis and endothelial swelling. The favorable effects of fish oil feeding on serum lipids may have a protective effect on the development of glomerular damage.