Role of keto acids in the prophylaxis and treatment of renal osteopathy

KA administration given in addition to a low-protein diet leads to a reduction of PTH secretion followed by diminishing of osteofibrosis. Osteomalacia will also be reduced by a better control of the calcium-phosphate metabolism, an increase of 1,25-(OH)2-D levels, and a lower burden of aluminum. Therapeutic levels of 25-OH-D and calcitonin (caused by simultaneous administration of vitamin D) are probably necessary to achieve this effect. KA are not only the optimum form of substitution in the nutritional treatment of chronic renal failure, but they seem to be very effective in the treatment of renal osteodystrophy.

Plasma amino and keto acids in chronic renal failure

During both early and late stages of chronic renal insufficiency the response of BCKA to the disease state, as indicated by plasma levels, differs from that of BCAA. Val is the only BCAA whose concentration changes under the conditions of our study, and this only during the more advanced stages of disease. In contrast, all three BCKA declined, KIVA and KICA even in mild renal failure, showing that already during the early stages of the disease these BCKA levels are decreased. BCKA are more sensitive parameters than the corresponding amino acids with regard to the metabolic dysfunctions characteristic of this disease. Modern analytical methods allow more exact and reliable knowledge of these indicators and thus a better understanding of biochemical mechanisms, possibly resulting in better therapy.

Therapeutic effect of keto acids on renal osteodystrophy. A prospective controlled study

The therapeutical effect of keto acids on bone histology was investigated in a prospective randomized controlled study of 40 patients. A marked improvement in osteofibrotic as well as in osteomalacic changes was found in bone biopsies after 12 months of treatment with keto acids.

[Method and initial results of percutaneous ultrasound-controlled sclerotherapy of parathyroid adenoma in secondary or tertiary hyperparathyroidism]

In 16 of 96 patients with clinical, roentgenological and biochemical signs of hyperparathyroidism due to chronic renal failure the parathyroid adenomas were detected ultrasonographically. Verification of the adenoma was done using fine-needle biopsy and cytological evaluation. In 8 patients an ultrasonographic-guided sclerotherapy using absolute ethanole was performed. The efficacy of this method was evaluated by control of the biochemical parameters. In all cases a reduction of the serum calcium level and of the parathormone was observed. This method may represent an adjuvant therapy in the treatment of renal hyperparathyroidism.

What can be safely said about predialysis treatment?

The modern principles of protein restriction and concomitant treatment in the predialysis period were explained. Our own data of a prospective study show the superiority of a keto acid-substituted diet with regard to the progression of chronic renal failure. The advantage of a keto acid administration was underlined.

Conservative long-term treatment of chronic renal failure with keto acid and amino acid supplementation

In a group of 119 patients with advanced chronic renal failure (serum creatinine level 733 +/- 186 mumol/l) the effect of a low-protein diet supplemented with essential amino acids (EAA) or their keto analogues (KA) on uremic metabolism and rehabilitation status was investigated. The protein intake amounted to 0.4 g/kg B.W./day, the phosphorus intake 0.4-0.6 g/day and the energy supply 120-150 kJ/kg B. W./day. In 51 patients there was a substitution with EAA and in 68 patients with their KA. The mean duration of dietary treatment in this study was 19 months (6-64 months). During this time, the serum creatinine increased from 733 +/- 186 to 1,220 +/- 256 mumol/l, whereas the urea nitrogen values remained relatively constant at between 26 and 30 mmol/l. There were no signs of protein malnutrition (nitrogen balance, serum transferrin and serum protein were normal). The hemoglobin concentration remained at greater than 5 mmol/l with creatinine levels of 1,220 +/- 256 mumol/l. During the substitution with KA, there was a significantly greater decrease in serum phosphate (p less than 0.05) and parathyroid hormone (PTH) (p less than 0.01) as compared with the uremics given EAA. In addition, we found a significant increase in testosterone (p less than 0.01) in patients supplemented with KA. Despite advanced chronic renal failure there was a good degree of rehabilitation (full-time work: 21%; part-time work: 66.4%). It can be concluded that a low-protein diet supplemented with EAA or KA can improve the uremic metabolism, rehabilitation status and safely postpone the start of maintenance dialysis.

Influence of keto acid (KA) treatment on renal osteodystrophy

A marked improvement of renal osteodystrophy was achieved after a combined treatment with keto acids and vitamin D in patients with chronic renal failure. Results were checked by histological investigations. The biochemical background of the successful treatment was analysed. A regression of hyperparathyroidism and improvement in vitamin D status are the cause of this phenomenon.

Suppression of parathyroid hormone by therapy with a mixture of keto analogues/amino acids in hemodialysis patients

In the present study the influence of a mixture of keto analogues/amino acids (KA) on PTH levels in 18 RDT patients was examined. Ten of them were treated with KA over a period of 3 months, while the other 8 patients served as control group. The KA-treated patients showed a significant fall in PTH and plasma phosphate levels, while no changes of plasma 25-OH-D or plasma calcitonin were observed. Consequently, KA administration may also be beneficial with respect to control of secondary hyperparathyroidism.

Successful pregnancy of a woman with advanced renal failure on nutritional treatment

A case is reported of a successful pregnancy of a woman with advanced renal failure treated nutritionally. The importance of an intensive interdisciplinary medical co-working is stressed, and the individual adaptation of the dietary treatment to the special nutritional requirements in pregnancy is discussed.

[Controlling renal osteopathy with keto acids]

Starting from the results of former investigations the influence of the long-term treatment with the KA of the essential amino acids on the renal osteopathy is investigated. For this purpose we compared 27 patients with renal insufficiency (serum creatinine 981 +/- 354 mumol/l), who besides vitamin D had been treated with KA for at least 12 months, to a group of 50 patients (serum creatinine 778 +/- 273 mumol/l), who had received vitamin D over 19 +/- 9 months, and to a control group of 27 patients (serum creatinine 928 +/- mumol/l) without an adequate conservative therapy. While the control group showed the typical constellation in advanced renal insufficiency with hypocalcaemia, hyperphosphataemia, clearly increased PTH levels, clearly increased CT values and normal 25-OH-D concentrations, during the diettherapy and the vitamin D substitution a significant increase of the serum levels of calcium, 25-OH-D and CT as well as a significant decrease of the PTH and the anorganic phosphate in the serum developed. Under the combination therapy with KA and vitamin D despite the reduction of the phosphate binders another significant decrease of the PTH and the anorganic phosphate was observed. The mineral content of the bones was within the normal in the two therapy groups. The percentage of the normal histological findings of the bones was with 40.7% highest despite the advanced renal insufficiency in the simultaneous substitution with KA. While in the vitamin D group during the control biopsy after 12 months in 20.5% of the cases an improvement of the histological findings developed, this effect occurred under additional KA-therapy in 51.9% of the cases. The results allow the conclusion that by means of the long-term treatment with KA a favourable influence on the renal osteopathy develops.

Influence of keto acids on serum parathyroid hormone levels in patients with chronic renal failure

The metabolic effects of short-term and long-term treatment by keto acids were examined in 46 patients with chronic renal failure. Long-term as well as short-term administration to chronic uremics resulted in a significant reduction of serum PTH and inorganic phosphate levels while serum concentrations of serum calcium, 25-OH-D and calcitonin were not influenced. The results presented in this paper allow the conclusion that keto acid treatment of patients with chronic renal failure may be helpful in the control of abnormal calcium-phosphate metabolism and secondary hyperparathyroidism.

Relation between middle molecules and parathyroid hormone in patients with chronic renal failure

In 10 moderately and 41 severely uremic patients the relation between serum parathyroid hormone (PTH) and middle molecule fraction 2 (MMS fr. 2-corresponding to MMS peak 7 of Fürst) was investigated. A significant correlation between PTH and MMS fr. 2 levels was found. This correlation was even better between PTH levels and MMS fr. 2/creatinine ratios. We would like to propose that PTH is one of several factors regulating middle molecule levels in uremic patients and that some 'toxic' effects of PTH may be mediated by middle molecules.

Serum 25-hydroxyvitamin D in patients with chronic renal failure on long-term treatment with high doses of vitamin D2

The present study was aimed at answering the following two questions: (1) What is the effect of high dose vitamin D treatment on the serum level of 25-hydroxyvitamin D (25-OH-D) in patients with chronic renal failure (CRF)? (2) Is there any effect of urinary protein loss on the serum 25-OH-D levels during treatment with pharmacological doses of vitamin D? 42 patients with CRF were studied. They were treated conservatively by a low protein diet and received 15 mg of vitamin D2 once a week. Long-term administration of vitamin D caused a significant (5- to 7-fold) increase of plasma 25-OH-D level irrespective of the degree of proteinuria. This increase was noted only during the first 5 months of vitamin D2 treatment. Surprisingly only in some patients moderate hypercalcemia (> 2.75 mmol/l) was found. From the results obtained it is concluded that (1) patients with CRF differ from normal subjects in handling of high doses of vitamin D and (2) high dosage treatment with vitamin D may prevent hypocalcemia in patients with CRF in spite of high proteinuria.