The analytic framework illustrates the relationship between infants, children, adolescents, and adults with PKU and females with PKU who become pregnant, treatment choices for PKU, monitoring, outcomes, and harms. Patients may choose a Phe-restricted diet alone or a Phe-restricted diet in conjunction with treatment with sapropterin dihydrochloride or large neutral amino acids, followed by monitoring of Phe levels. Depending upon the Phe level the treatment may be altered. Therapies may lead to intermediate and long-term outcomes and harms. Intermediate treatment outcomes include decreased Phe levels in the blood and improved Phe tolerance. Therapies may also lead to long term outcomes, including changes in quality of life, normal growth, nutritional outcomes, and cognitive development. Outcomes in infants of mothers with PKU include the prevention of neurologic impairment and cardiac defects and normal growth.

Figure 1Analytic framework for treatment questions

BH4 = sapropterin dihydrochloride; LNAAs = large neutral amino acids; Phe = phenylalanine; PKU = phenylketonuria

* Encompasses a full range of specific negative effects, including the narrower definition of adverse events. Can include costs, medical side effects, poor quality of life, etc.

Note: Numbers in circles indicate the positioning of Key Questions in the treatment process.

From: Methods

Cover of Adjuvant Treatment for Phenylketonuria (PKU)
Adjuvant Treatment for Phenylketonuria (PKU) [Internet].
Comparative Effectiveness Reviews, No. 56.
Lindegren ML, Krishnaswami S, Fonnesbeck C, et al.

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