Tetrahydrobiopterin responsiveness in a series of 53 cases of phenylketonuria and hyperphenylalaninemia in Iran

To determine the prevalence of 6R-Tetrahydrobiopterin (BH4) responsive phenylketonuria (PKU) in 53 cases of patientswith various classification of hyperphenylalaninemia and PKUExcluding the BH4 deficient type referring to children's medical center in Iran (phenylalanine 360-2420 mu mol/L), the single dose of 20 mg/kg (Kuvan (R)) and duration of 24 h was used. Results: Among the 4 different categories of mild hyperphenylalaninemia requiring treatment, mild, moderate and classic PKU, the BH4 responders were 90%, 35.7%, 5.6% and 0% respectively after 24 h. Conclusion: BH4 responsiveness ismore prevalent in mild hyperphenylalaninemia and mild PKU patients in Iran. (C) 2015 The Authors. Published by Elsevier Inc.