Specific characteristics of dynamic monitoring of patients diagnosed with classical phenylketonuria during pregnancy

Background. The main therapy for phenylketonuria is a specialised diet with restriction of natural protein, respectively phenylalanine with the prescription of specialised therapeutic foods based on amino acids without phenylalanine. Diet therapy is prescribed as soon as hyperphenylalaninaemia is detected. It is very important to continue treatment for life, and it is equally important that patients maintain ongoing adherence to treatment. However, this therapy significantly limits the consumption of natural foods and requires the use of amino acid mixtures, so the vast majority of patients in adolescence and adulthood have difficulty following the diet, giving up specialised foods and switching to a normal diet. This situation leads to the gradual development of prolonged metabolic decompensation, and intoxication with high concentrations of phenylalanine and its derivatives. This is especially dangerous for women of fertile age diagnosed with classical phenylketonuria who are planning pregnancy or are pregnant. A hypophenylalanine diet with control of blood phenylalanine levels is the basic principle of prevention of maternal phenylketonuria syndrome. However, often the caloric, fat, and carbohydrate requirements of the diet cannot be compensated by prescribing one specialised therapeutic food or compensated by natural foods. The use of a regimen of two specialised therapeutic foods for the treatment of patients with phenylketonuria during pregnancy can prevent a metabolic catastrophe and protect the foetus from teratogenic effects.

Results. An example is given of a combination of specialised therapeutic foods that provide both an increased protein equivalent content and a supplementation of macroand micronutrient demands.

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