Molecular genetics and impact of residual in vitro phenylalanine hydroxylase activity on tetrahydrobiopterin responsiveness in Turkish PKU population.

Background: The prevalence of phenylalanine hydroxylase (PAH)-deficient phenylketonuria (PKU) in Turkey is high (1 in 6500 births), but data concerning the genotype distribution and impact of the genotype on tetrahydrobiopterin (BH(4)) therapy are scarce.

Objective: To characterize the phenotypic and genotypic variability in the Turkish PKU population and to correlate it with physiological response to BH(4) challenge.

Methods: We genotyped 588 hyperphenylalaninemic patients and performed a BH(4) loading test (20mg/kg bw) in 462 patients.

Corticospinal tract involvement in a patient with 3-HMG coenzyme A lyase deficiency.

3-Hydroxy-3-methylglutaryl coenzyme A lyase deficiency, an inborn error of ketone body synthesis and leucine degradation, is a rare disorder. There are few reports demonstrating clinical and neuroradiologic findings of this condition. This report describes a 3.

Stroke in childhood: experience in Istanbul, Turkey.

Our objective was to characterize the etiologic factors and outcome for stroke in children. We retrospectively reviewed the charts of patients between the ages of 40 days and 94 months (36.5 +/- 23.

Screening for tetrahydrobiopterin deficiencies using dried blood spots on filter paper.

Tetrahydrobiopterin (BH4) deficiency among newborns with hyperphenylalaninemia must be rapidly diagnosed and distinguished from classical phenylketonuria (PKU) to initiate immediately specific treatment and to prevent irreversible neurological damage. The characteristic pattern of urinary pterins makes it possible to differentiate between PKU and BH4 deficiencies, and to identify different variants of BH4 deficiency. However, collection, storage, and shipment of urine samples for pterin analysis is cumbersome.

Biotinidase deficiency: novel mutations and their biochemical and clinical correlates.

Biotinidase deficiency is a defect in the recycling of the vitamin biotin. Biotin supplementation can markedly improve the neurological and cutaneous symptoms of affected children and prevent symptoms in children identified by newborn screening or treated since birth. We have determined thirteen novel mutations in children with the disorder.

Type II hyperprolinemia: a case report.

Hyperprolinemia type II (HP II) is a rare inherited metabolic disease due to the deficiency of pyroline-5-carboxylate dehydrogenase. It is generally believed to be a benign condition although some patients have neurological problems such as refractory convulsions. Here we report a six-year-old girl with HP II who admitted to our hospital with recurrent seizure refractory to multiple antiepileptic drugs.