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Background Phenylketonuria (PKU) is an inherited error of metabolism, screened at 48–72 h of life since 1975 in Hungary. The patients have to keep a strict lifelong protein-restricted diet, resulting in PKU and its treatment can lead to social and financial burdens. The current study aimed to evaluate the health-related quality of life (HRQoL) of children living with PKU. Patients and methods A single-centre, cross-sectional, observational study was conducted at the Center of Newborn Screening and Inherited Metabolic Disorders of Budapest, Hungary, using the PKU-quality of life (PKU-QoL) questionnaire. Responses of 59 parents and 11 teenagers were collected. Numerous aspects regarding HRQoL were analysed according to clinical compliance and severity. The patients were classified into groups with good or suboptimal adherence based on regular phenylalanine (Phe) values. The online officially translated versions of the adolescent or parental PKU-QoL questionnaire were used and analysed anonymously. Differences in HRQoL were compared - PKU vs. Hyperphenylalaninaemia (HPA) and good vs. suboptimal adherence. Results Twenty-five of 32 examined parameters had no or little impact on HRQoL. The most frequently reported symptom was irritability. Food enjoyment was the most impacted domain, with a major severity score in the adolescent group (median 62,5, IQR: 25–75). The emotional impact was scored at moderate severity by both the adolescents and parents. Classical PKU patients with good metabolic control were more frequently tired than HPA patients (0,0027). The group with poor metabolic adherence showed more frequent tiredness (p = 0,03), slow thinking (p = 0,018) and anxiety (p = 0,015). Conclusion Overall, our patients showed an excellent HRQoL; most domains (29/36) were reported as little/no impacted. Worse QoL was found in patients with suboptimal metabolic control. Particular attention should be paid to the emotional health of PKU patients.

Abstract: Since the initial breaking discovery of Følling that the severe neurological consequences of phenylketonuria could be prevented by use of low phenylalanine (Phe) diet, it has been shortly recognised that defective phenylalanine metabolism may also arise from the deficiency of tetrahydrobiopterin (BH4) cofactor, required for phenylalanine-hydroxylase activity. Furthermore, as BH4 is in Phe metabolism, it is also a cofactor for the activities of tyrosine hydroxylase and tryptophane hydroxylase, enzymes required for the synthesis of catecholamines and serotonin neurotransmitters. Besides hyperphenylalaninemia in patients with tetrahydrobiopterin deficiencies, dopamine and serotonin deficiencies, with different disorders of the central nervous system also develop. Mild form of tetrahydrobiopterin deficiency is rare, most of the patients have severe neurological abnormalities including progressive mental retardation if not treated properly. Early diagnosis and treatment are essential and can improve the clinical course and prognosis. Orv Hetil. 2017; 158(48): 1897–1902.

Elevated maternal phenylalanine levels during pregnancy are teratogenic, and may result in embryo-foetopathy, which could lead to stillbirth, significant psychomotor handicaps and birth defects. This foetal damage is known as maternal phenylketonuria. Women of childbearing age with all forms of phenylketonuria, including mild variants such as hyperphenylalaninaemia, should receive detailed counselling regarding their risks for adverse foetal effects, optimally before contemplating pregnancy. The most assured way to prevent maternal phenylketonuria is to maintain the maternal phenylalanine levels within the optimal range already before conception and throughout the whole pregnancy. Authors review the comprehensive programme for prevention of maternal phenylketonuria at the Metabolic Center of Budapest, they survey the practical approach of the continuous maternal metabolic control and delineate the outcome of pregnancies of mothers with phenylketonuria from the introduction of newborn screening until most recently.Phenylketonuriában szenvedő várandós anya vérének emelkedett phenylalanin-koncentrációja a magzatra teratogén hatással van, embryo-foetopathiát okoz. Élveszülés esetén a kórkép jellemzői az intrauterin sorvadás, az általában jelentős fokú pszichomotoros retardáció és a gyakori fejlődési rendellenességek. Az így kialakuló tünetcsoportot maternális phenylketonuria szindrómának nevezzük. Azoknak a fogamzóképes korba került nőknek, akik vérében a phenylalanin-koncentráció a normálisnál magasabb, akár a phenylketonuria bármely formája, akár az egyébként ke zelést nem igénylő enyhe variáns, a hyperphenylalaninaemia esetén, még a gyermek vállalása előtt részletes felvilágosításban kell részesülniük arról a potenciális veszélyforrásról, amit állapotuk/betegségük a magzatra nézve jelenthet. A maternális phenylketonuria megelőzésének legbiztosabb módja, ha a fogamzás előtt és mindvégig a terhesség alatt az anyai vér phenylalanin-koncentrációja a normális tartományban van. A szerzők a Budapesti Anyagcsere Szűrő és Gondozó Központban a megelőzés érdekében tett intézkedéseket, valamint a gondozás gyakorlati kérdéseit ismer tetik, és áttekintik a budapesti központhoz tartozó phenylketonuriás anyák várandósságainak kimenetelét a hazai phenylketonuria-szűrés bevezetésétől napjainkig. Orv. Hetil., 2013, 154, 683–687.

Pearson syndrome is a multisystem juvenile condition associated with deletions in the mitochondrial genome. The most common 4977 bp deletion of mitochondrial DNA (mtDNA) can mainly be detected in the patients' peripheral blood. Here we report a child with a clinically unclarified diagnosis where molecular genetic results proved Pearson syndrome from stored dried blood sample 6 months after the patient's death. PCR amplification around the breakpoint of the most common mtDNA deletion could detect the presence of mutated mtDNA. Another polymerase chain reaction (PCR) assay indicated the low level of wild type mtDNA in patients' blood. We believe that this case shows the importance of storing Guthrie card and the availability of detection of Pearson syndrome from dried blood sample.