Problems related to diet management of maternal phenylketonuria

Abstract

Provision of nutritionally complete elemental diets for pregnant women with PKU requires greater knowledge of 'conditionally' essential nutrient requirements than is presently available as well as application of known information. Formulation of elemental products needs to be improved to enhance aroma and taste and to decrease osmolality. Designers of the metal and vitamin components should keep in mind that a major portion (70-80%) of most of these nutrients must be obtained from the elemental products. Thus deletion of suspected essential minerals or vitamins could cause serious deficiencies. On the other hand, knowledge of appropriate ratios that make for improved trace metal absorption should be applied. Clinical nutritionists need to assist patients in selection of foods that are low in binding substances and provide 'conditionally' essential nutrients in adequate amounts. Closer cooperation between clinical nutritionists, nutrition scientists and food technologists should result in improved elemental products for care of pregnant women with PKU.

Phenylketonuria: Dietary and therapeutic challenges

“…In fact, it has been observed that this type of diet may produce nutritional deficits (Acosta and Stepnick-Gropper 1986), with consequences for growth and development. Studies highlight inadequate intake of taurine (Agostoni et al 1990), carnitine (Schulpis et al 1990) and other micronutrients mostly contained in animal-derived food that is not permitted in the diet of PKU patients.…”

Management of Inborn Errors of Metabolism during Pregnancy

“…Acosta and Stopnick-Gropper (34) have discussed the physicochemical problems which can result from the osmolality of the various available amino acid solutions. A typical mixture for the phenylketonuric mother which provides the equivalent of 60 g protein daily and is diluted to 500 ml with water will have an osmolality of around 1900 mosm/kg water.…”