[Nutrition in congenital metabolic diseases]

Today we know a great number of inborn errors of metabolism which can be treated by a special diet. The principle of therapy consists in a reduction or elimination of certain substances from feeding or in supply of substances which cannot be synthesized by the organism. The method of withdrawing these substances which cannot be degradated, as Phenylalanine in Phenylketonuria, was translated later to other disturbances as in the degradation of carbohydrates and lipids. In certain diseases, especially in those with hyperammonemia, it is possible only with a decrease in protein intake to overcome the illness, in others cofactor therapy in great doses may help. In phenylketonuric mothers diminishing of Phenylalanine in diet may avoid the non-phenylketonuric child of intrauterine Phenylalanine intoxication. The period in which therapy must be given is different. In some diseases diet can be finished after some years, in others it must be continued for the whole life.