Hyperphenylalaninemia

increased levels of phenylalanine in the blood
AR hereditary, gene is on 12. chromosome, incidence is 1:10 000

Types[edit | edit source]

phenylalanine hydroxylase defect - classical phenylketonuria (PKU)
dihydrobiopterin reductase defect - atypical phenyketonuria
dihydrobiopterin biosynthesis defect (phenylalanine hydroxylase cofactor) - atypical phenylketonuria
phenylalanine increased only to 0.6 mmol / l is called "hyperphenylalaninemia"

Pathogenesis[edit | edit source]

The pathogenesis of HPA is the same as for other types, but it does not have nearly the same effect as classical phenylketonuria and is essentially disease-free.

Thus, hyperphenylalaninemia is only an increased amount of phenylalanine in the blood of a patient's normal diet.

Screening[edit | edit source]

Blood testing of a two-week-old newborn for phenylketonuria

For more information see Neonatal screening.

we use capillary blood from foot 2. − 3. day after birth

at the time of collection, the newborn should have been on dairy food for at least three days
when the child is released from the maternity hospital on the 2nd or 3rd day - we will take the screening, but after the release the practitioner will ensure the collection of capillary blood for a control examination
from 1 October 2009, newborn neonatal screening is performed using the tandem mass spectrometry method
formerly: Guthrie's method - we have Bacillus subtilis and its competitive inhibitor on agar, we add blood, in the presence of Pha it starts to grow

Diagnosis[edit | edit source]

diagnosis can be made from the blood at the metabolic and molecular level, enzymatic examination from liver biopsy is not needed for diagnosis or treatment, but all children with PKU need to be examined pterin metabolism to differentiate forms

Links[edit | edit source]

External resources[edit | edit source]

Source[edit | edit source]

References[edit | edit source]

HRODEK, Otto and Jan VAVŘINEC, et al. Pediatrics. 1st edition. Prague: Galén, 2002. ISBN 80-7262-178-5 .

ŠAŠINKA, Miroslav, Tibor ŠAGÁT and László KOVÁCS, et al. Pediatrics. 2nd edition. Bratislava: Herba, 2007. ISBN 978-80-89171-49-1 .