Margreet E. van Rijn

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BACKGROUND The etiology of reduced bone mineral density (BMD) in phenylketonuria (PKU) is unknown. Reduced BMD may be inherent to PKU and/or secondary to its dietary treatment. MATERIALS AND METHODS Lumbar BMD was measured by dual-energy X-ray absorptiometry in 53 early and continuously treated PKU patients (median age 16, range 2-35 years). First,(More)
For almost all patients with PKU, a low phenylalanine diet is the basis of the treatment despite a widely varying natural protein tolerance. A vitamin and mineral supplement is essential and it is commonly added to a phenylalanine-free (phe-free) source of L-amino acids. In PKU, many phe-free L-amino acid supplements have age-specific vitamin and mineral(More)
Patients with phenylketonuria (PKU) encompass an 'at risk' group for micronutrient imbalances. Optimal nutrient status is challenging particularly when a substantial proportion of nutrient intake is from non-natural sources. In PKU patients following dietary treatment, supplementation with micronutrients is a necessity and vitamins and minerals should(More)
BACKGROUND Within Europe, the management of pyridoxine (B6) non-responsive homocystinuria (HCU) may vary but there is limited knowledge about treatment practice. AIM A comparison of dietetic management practices of patients with B6 non-responsive HCU in European centres. METHODS A cross-sectional audit by questionnaire was completed by 29 inherited(More)
OBJECTIVE To evaluate the adequacy of dietary treatment in patients with phenylketonuria, the monitoring of plasma phenylalanine and tyrosine concentrations is of great importance. The preferable time of blood sampling in relation to the nutritional condition during the day, however, is not known. It was the aim of this study to define guidelines for the(More)
BACKGROUND Dietary phenylalanine restriction is the cornerstone of phenylketonuria (PKU) management. However, there are no European consensus guidelines for its optimal dietary care. METHODS Detailed information on the routine dietary management of PKU was obtained from 10 European centres using structured questionnaires. Each centre was represented by(More)
The usual treatment for phenylketonuria (PKU) is a phenylalanine-restricted diet. Following this diet is challenging, and long-term adherence (and hence metabolic control) is commonly poor. Patients with PKU (usually, but not exclusively, with a relatively mild form of the disorder) who are responsive to treatment with pharmacological doses of(More)
The same basic principles are used to deliver dietary treatment in PKU that was developed sixty years ago. Dietary treatment is undoubtedly very successful, but it has gradually evolved and been guided commonly by individual experience and expert opinion only. There is little international consensus about dietary practice with improvements in specialist(More)
Notwithstanding the success of the traditional dietary phenylalanine restriction treatment in phenylketonuria (PKU), the use of large neutral amino acid (LNAA) supplementation rather than phenylalanine restriction has been suggested. This treatment modality deserves attention as it might improve cognitive outcome and quality of life in patients with PKU.(More)
Patients with phenylketonuria (PKU) must follow a strict low-phenylalanine (Phe) diet in order to minimise the potentially disabling neuropsychological sequelae of the disorder. Research in this area has unsurprisingly focussed largely on managing blood Phe concentrations to protect the brain. Protein requirements in dietary management of PKU are met mostly(More)