RESUMO
OBJECTIVE: To compare a gram protein exchange system (1g=50-mg Phenylalanine) with a unit exchange system (1unit=15-mg Phenylalanine) and its effect on the blood Phenylalanine (Phe) levels and acceptance in the dietary management for children and adolescents with Phenylketonuria. METHODS: In Phase One, participants were randomised to continue counting Phe unit exchanges (n=8) or changed to counting gram protein exchanges (n=10), using a new diet chart developed in-house. Foods containing less than 20mg Phe per serve were now considered "free." Interim data analysis confirmed no significant deterioration in Phe levels of the study group and the control group was changed to protein counting.In Phase Two, 18 participants were educated to use an updated version of the in-house diet chart - in this version foods containing less than 50mg Phe per serve were considered "free."In both phases, attitudes to PKU and its management were evaluated at baseline and 6months. Phenylalanine and tyrosine levels were measured from filter paper blood spots by tandem mass spectrometry. RESULTS: Phase One: Phe levels over 6months were comparable to pre-study levels (mean Phe pre 366µmol/L+/- 169, mean Phe post change=388µmol/L+/- 160).Phase Two: Four participants had a significant improvement in blood Phe levels, nine showed no significant change and one participant's levels were significantly higher. There was incomplete data on four participants. All participants preferred the freer diet chart. CONCLUSION: Protein exchanges (foods containing less than 50mg Phe/serve uncounted) are an alternative method of measuring Phe intake in the dietary management of Phenylketonuria.
RESUMO
In a 12-month study, nine boys, aged 4.8-15.6 years, with bone ages 4.6-13 years, with moderate to severe chronic renal failure and resultant growth failure were treated with daily recombinant human growth hormone (rhGH), in conjunction with a strict low-protein/low-phosphate diet supplemented with keto and amino forms of the essential amino acids, histidine and additional energy. Improved growth had previously been observed with this dietary management over that obtained with conventional treatment for chronic renal failure. Each child had been on this diet for at least 2 years before rhGH was commenced. Mean height velocity increased from 4.6 +/- 1.3 to 9.0 +/- 1.3 cm/year (P < 0.001) in the pre-pubertal group, and in the pubertal group from 5.4 +/- 1.4 to 10.4 +/- 1.8 cm/year (P < 0.01). The mean height velocity standard deviation scores (SDSs) increased from -1.2 +/- 0.6 to +2.3 +/- 0.9 (P < 0.001) in the pre-pubertal group and from -0.4 +/- 0.6 to +1.9 +/- 1.1 (P < 0.01) in the pubertal group. Mean height SDS for chronological age increased from -2.2 +/- 0.7 to -1.5 +/- 0.5 (P < 0.01) in the pre-pubertal group and from -1.9 +/- 0.7 to -1.3 +/- 0.9 in the pubertal group (P < 0.02). There was no significant deterioration in renal function or renal bone disease, and bone age did not advance more than chronological age over the 12-month period.
