Long-term effects of a new ketoacid-amino acid supplement in patients with chronic renal failure.

Long-term effects of a new ketoacid–amino acid supplement in patients with chronic renal failure. Nine patients with severe chronic renal failure (mean glomerular filtration rate 4.8 ml/min; mean serum creatinine 11.3 mg/dl) who were previously on a protein-restricted diet were treated with a diet containing an average of 33 kcal/kg and 22.5 g/day of mixed quality protein, supplemented by a combination of amino acids and mixed salts formed between basic amino acids and keto-analogues of essential amino acids. The supplement was designed to minimize or reverse the amino acid abnormalities of chronic renal failure rather than to meet the normal requirements for the essential amino acids; it contained tyrosine, ornithine, and a high proportion of branched-chain ketoacids, but no phenylalanine or tryptophan and very little methionine. Within one month, serum urea nitrogen fell and serum albumin and transferrin rose significantly; serum creatinine fell slightly. Hyperphosphatemia (present in three patients) was corrected. Nitrogen balance, measured in seven of the nine patients, on the average was neutral, as it was in a preceding control period on a 40 to 50 g/day protein diet. Plasma tyrosine and threonine, which were subnormal before therapy, rose to normal or high normal levels. Branched-chain amino acids did not change. During a total of 63 patient-months of therapy, no side effects or toxicity were observed, and serum albumin and transferrin did not change further. It is concluded that this specially designed supplement added to a 20 to 25 g/d protein diet is an acceptable regimen which can improve or maintain protein nutrition in patients with severe chronic renal failure who would otherwise require dialysis. Effet a long terme d'un nouveau melange de cetoacides – d'amino acides chez des malades ayant une insuffisance renale chronique. Neuf malades ayant une insuffisance renale chronique severe (filtration glomerulaire moyenne 4,8 ml/mn, creatininemie moyenne 11,3 mg/dl) recevant prealablement un regime pauvre en proteines, ont ete traites avec un regime apportant en moyenne 33 kcal/kg et 22,5 g/j de proteines mixtes, auquel a ete ajoute un melange d'acides amines et de sels d'acides amines basiques et de ceto-analogues d'acides amines essentiels. Ce supplement a ete concu plus pour diminuer ou supprimer les anomalies des acides amines au cours de l'insuffisance renale chronique que pour fournir les besoins normaux en acides amines essentiels; il contenait de la tyrosine, de l'ornithine et une grande proportion de cetoacides a chaines ramifiees, mais ni phenylalanine, ni tryptophane, et tres peu de methionine. En moins d'un mois, l'azote ureique plasmatique a baisse; la serum albumine et la transferine se sont elevees significativement, la creatininemie a legerement diminue. L'hyperphosphatemie (presente chez trois malades) a ete corrigee. La balance azotee, mesuree chez sept des neuf malades etait nulle en moyenne, comme elle l'etait au cours de la periode controle precedente, avec un regime comportant 40 a 50 g/j de proteines. La tyrosine et la threonine plasmatiques, inferieures a la normale avant traitement, se sont normalisees, ou ont atteint des valeurs a la limite superieure de la normale. Il n'y a pas eu de modification des concentrations d'acides amines a chaines ramifiees. Pendant un traitement durant au total 63 mois-malade, il n'a pas ete observe d'effet secondaire ni de toxicite, et il n'y a pas eu d'autre modification de l'albumine ou de la transferrine plasmatique. Il est conclu que ce melange specialement concu, rajoute a un regime apportant 20 a 25 g/j de proteines constitue un regime acceptable, permettant d'ameliorer ou de maintenir l'apport protidique chez des malades ayant une insuffisance renale chronique severe qui, autrement, necessiteraient la dialyse.