Phenylketonuria. II. Results of treatment of infants and young children. A report of 10 cases

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The Journal of Pediatrics




The results of dietary treatment of 10 infants and young children with phenylketonuria with a low phenylalanine diet (Lofenalac) from 6 months to 3 years (average 22 1/2 months per child) are presented. The group includes 4 babies started on the diet under 2 months of age, 1 at 8 months, and 4 from 1 to 3 years. The data include weights, heights, head circumferences, serum phenylalanine levels, electroencephalographic findings, personality and intelligence changes, and brief notes on individual diet control patterns. The following observations were made:1.Initial changes in behavior paralleled the decrease in the serum level of phenylalanine, which usually was within the "therapeutic range" one to two weeks after starting the diet. The children became less irritable and less withdrawn, and their responsiveness and attention span were increased.2.The 4 children who were placed on the diet prior to 2 months of age are developing within the normal and low-normal range.3.The 6 children started on the diet from 8 months to 3 years of age have an average I.Q. of 72.4.Ten normal siblings have an average I.Q. of 103, and 5 untreated siblings with phenylketonuria have an average I.Q. of 24.5.The children generally had somewhat slow growth patterns but were well nourished for their heights. Little difficulty was experienced in giving the special diet. There were no complications of the treatment such as diarrhea, marked weight loss, or anemia. One young infant (H-2) had an unexplained severe rash for several months during early treatment.6.Serum phenylalanine levels were usually maintained within a range of 1 and 8 mg. per 100 ml.7.Six of the 10 children initially had abnormal electroencephalograms; 2 of the 4 normal electroencephalograms were on infants started on the diet while under 2 weeks of age. Of the latest tracings during the dietary treatment, only one of the 10 was abnormal. Conversion from abnormal to normal took place after 1 1/2 months to 2 1/3 years (average 11 1/2 months) on the diet. © 1961 The C. V. Mosby Company.





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