The Influence of Phenylalanine Intake on the Chemistry and Behaviour of a Phenylketonuria Child
Tóm tắt
Summary
Phenylketonuria is a not uncommon cause of mental deficiency (there are probably 1600 cases in Great Britain alone). On the supposition that the high level of phenylalanine or its breakdown products in the blood and cerebrospinal fluid might be responsible for the mental retardation in this disorder we have treated a two year‐old child with a diet low in phenylalanine. The introduction of this diet was associated with an appreciable improvement in the patient's mental status and a fall in the level of phenylalanine in the blood and urine. When phenylalanine was again given in fairly large amounts there was an immediate and dramatic deterioration in the child's mental and biochemical condition. A similar phenylalanine intake produced no clinical reaction in a control child.
The main source of aminoacids in the diet was an acid casein hydrolysate which was specially treated to remove phenylalanine. The aim of the phenylalanine‐poor diet was to keep the phenylalanine blood level as near the normal range as possible. The preparation of such a diet presents little difficulty if a phenylalanine‐free casein hydrolysate is available. Its value in the treatment of other children is at present being investigated; it seems reasonable to assume that patients in the first two years of life will benefit most.
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Tài liệu tham khảo
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