Zusammenfassung
In recent years several studies on tetrahydrobiopterin
(BH4)-responsive phenylalanine hydroxylase (PAH) deficiency
have been published. The molecular mechanisms of BH4
responsiveness are not conclusively understood, but there
is evidence that BH4 responsiveness in
hyperphenylalaninaemia (HPA) depends on the patient's
genotype and residual PAH activity. As a BH4 preparation
will soon obtain marketing approval as an alternative
treatment for phenylketonuria (PKU), it is particularly
important to evaluate this treatment and to define criteria
to identify patients with a potential benefit from it. Most
of the patients found to be BH4-responsive suffered from
mild PKU or mild hyperphenylalaninaemia (MHP) and some of
these would not be treated at all in many countries. Of
patients with moderate and classic forms of PKU, only a few
were classified as responders and the clinical significance
of the effect size may be small.
Nutzer