Six-year follow up of phenylalanine intakes and plasma phenylalanine concentrations

Abstract

The daily Phe intakes of normally growing 1- to 6-year-old treated PKU patients were evaluated. The children received protein in amounts that varied from 2.26 +/- 0.47 g/kg body weight per day (mean +/- SD) at the age of 6 to 1.81 +/- 0.35 at the age of 72 months. Mean Phe intakes declining from 34 +/- 7 at the age of 6 months to 15 +/- 5 mg/kg body weight per day at the age of 72 months were required to maintain mean median plasma Phe levels around 6.0 mg/dl.

Correlation of age‐specific phenylalanine levels with intellectual outcome in patients with phenylketonuria

“…Patient compliance to dietary recommendations tends to decrease after early childhood ). Wendel et al (1990) reported a steady decrease in frequency of blood Phe level monitoring after 6 months of age. In addition to reduced blood Phe monitoring, there is a continual increase in Phe concentrations as patients age.…”

“…The participants' protein intake per kg body weight decreased by approximately 20 percent whereas Phe intake dropped approximately 56 percent (Wendel et al 1990). …”

“…Wendel et al (1990) analyzed the average protein and Phe intakes needed to maintain appropriate plasma Phe in children from birth to six years of age. These children consumed an average of 2.26 g protein per kg body weight at 6 months and 1.81 g/kg at 6 years.…”

“…Several collaborative PKU studies demonstrated a continual increase in mean Phe levels in those older than 4 years of age in relation to liberalization of diet restrictions and decreased frequency of blood Phe monitoring (Smith and Beasley 1989;Wendel et al 1990;Burgard et al 1997). Among an observational study of 330 patients under 20 years of age, 30% of blood Phe levels were above the maximum recommended value in those less than 4 years, 50% in those 5 to 10 years, and 80% in those 15 to 19 years of age .…”

Plasma thiols and their determinants in phenylketonuria

“…Plasma phenylalanine and methionine were analyzed by ion exchange chromatography with an LKB Biochrom 20 analyser (Pharmacia Biotech, Cambridge, England). The index of dietary control (IDC) was calculated as the average of the medians of plasma phenylalanine concentrations (Wendel et al, 1990) obtained every 6 months of metabolic monitoring of patients (phenylalanine was measured every 15 days on dried blood spot samples). All samples were obtained after a 10-h overnight fast.…”