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Contains fulltext : 182674.pdf (Publisher’s version ) (Open Access) Phenylketonuria (PKU) is an autosomal recessive inborn error of phenylalanine metabolism caused by deficiency in the enzyme phenylalanine hydroxylase that converts phenylalanine into tyrosine. If left untreated, PKU results in increased phenylalanine concentrations in blood and brain, which cause severe intellectual disability, epilepsy and behavioural problems. PKU management differs widely across Europe and therefore these guidelines have been developed aiming to optimize and standardize PKU care. Professionals from 10 different European countries developed the guidelines according to the AGREE (Appraisal of Guidelines for Research and Evaluation) method. Literature search, critical appraisal and evidence grading were conducted according to the SIGN (Scottish Intercollegiate Guidelines Network) method. The Delphi-method was used when there was no or little evidence available. External consultants reviewed the guidelines. Using these methods 70 statements were formulated based on the highest quality evidence available. The level of evidence of most recommendations is C or D. Although study designs and patient numbers are sub-optimal, many statements are convincing, important and relevant. In addition, knowledge gaps are identified which require further research in order to direct better care for the future.

Background The definitive dietary management of propionic acidaemia (PA) is unknown although natural protein restriction with adequate energy provision is of key importance. Aim To describe European dietary practices in the management of patients with PA prior to the publication of the European PA guidelines. Methods This was a cross-sectional survey consisting of 27 questions about the dietary practices in PA patients circulated to European IMD dietitians and health professionals in 2014. Results Information on protein restricted diets of 186 PA patients from 47 centres, representing 14 European countries was collected. Total protein intake [PA precursor-free L-amino acid supplements (PFAA) and natural protein] met WHO/FAO/UNU (2007) safe protein requirements for age in 36 centres (77%). PFAA were used to supplement natural protein intake in 81% (n = 38) of centres, providing a median of 44% (14–83%) of total protein requirement. Seventy-four per cent of patients were prescribed natural protein intakes below WHO/FAO/UNU (2007) safe levels in one or more of the following age groups: 0–6 m, 7–12 m, 1–10 y, 11–16 y and > 16 y. Sixty-three per cent (n = 117) of patients were tube fed (74% gastrostomy), but only 22% received nocturnal feeds. Conclusions There was high use of PFAA with intakes of natural protein commonly below WHO/FAO/UNU (2007) safe levels. Optimal dietary management can only be determined by longitudinal, multi-centre, prospective case controlled studies. The metabolic instability of PA and small patient cohorts in each centre ensure that this is a challenging undertaking., 0, SCOPUS: ar.j, info:eu-repo/semantics/published

International audience; Vitamin A (retinol) fulfills multiple functions in vision, cell growth and differentiation, embryogenesis, the maintenance of epithelial barriers and immunity. A large number of enzymes, binding proteins and receptors facilitate its intestinal absorption, hepatic storage, secretion, and distribution to target cells. In addition to the preformed retinol of animal origin, some fruits and vegetables are rich in carotenoids with provitamin A precursors such as β-carotene: 6 μg of β-carotene corresponds to 1 μg retinol equivalent (RE). Carotenoids never cause hypervitaminosis A. Determination of liver retinol concentration, the most reliable marker of vitamin A status, cannot be used in practice. Despite its lack of sensitivity and specificity, the concentration of retinol in blood is used to assess vitamin A status. A blood vitamin A concentration below 0.70 μmol/L (200 μg/L) indicates insufficient intake. Levels above 1.05 μmol/L (300 μg/L) indicate an adequate vitamin A status. The recommended dietary intake increases from 250 μg RE/day between 7 and 36 months of age to 750 μg RE/day between 15 and 17 years of age, which is usually adequate in industrialized countries. However, intakes often exceed the recommended intake, or even the upper limit (600 μg/day), in some non-breastfed infants. The new European regulation on infant and follow-on formulas (2015) will likely limit this excessive intake. In some developing countries, vitamin A deficiency is one of the main causes of blindness and remains a major public health problem. The impact of vitamin A deficiency on mortality was not confirmed by the most recent studies. Periodic supplementation with high doses of vitamin A is currently questioned and food diversification, fortification or low-dose regular supplementation seem preferable.; La vitamine A (rétinol) a de multiples fonctions dans la vision, la croissance et la différenciation cellulaires, l’embryogenèse, l’entretien des barrières épithéliales, l’immunité, etc. De nombreux enzymes, protéines de liaison et récepteurs facilitent l’absorption digestive, le stockage hépatique, la sécrétion hépatocytaire et la distribution du rétinol aux cellules cibles. Hors le rétinol préformé d’origine animale, certains légumes et fruits sont riches en caroténoïdes à activité provitaminique A, comme le ß-carotène, dont 6 μg correspondent à 1 équivalent rétinol (ER). Les caroténoïdes n’entraînent jamais d’hypervitaminose A. La concentration hépatique, marqueur fiable du statut, étant, en pratique, inaccessible, on a recours, malgré son manque de sensibilité et de spécificité, à la rétinolémie. Une concentration inférieure à 0,7 μmole/L (200 μg/L) est un indicateur d’apports insuffisants. Une rétinolémie supérieure à 1,05 μmole/L (300 μg/L) reflète un statut satisfaisant. Les apports journaliers conseillés en ER vont de 250 μg à 7–36 mois jusqu’à 750 μg à 15–17 ans et sont satisfaits dans les pays industrialisés. Les apports dépassent les apports conseillés, voire les limites de sécurité (600 μg/j) chez certains nourrissons non allaités. La nouvelle réglementation européenne (2015) sur les préparations pour nourrissons et de suite, et la suppression des suppléments en rétinol non justifiés devraient en principe limiter cet excès d’apport. Dans certains pays en développement, la carence vitaminique A, cause majeure de cécité, reste d’actualité. Son impact sur la mortalité préscolaire n’apparaît plus dans des études récentes ; le recours aux charges semestrielles jusque-là recommandées est controversé, au profit d’une meilleure diversification alimentaire, voire d’aliments enrichis ou d’une supplémentation régulière à faible dose.

Item does not contain fulltext We developed European guidelines to optimise phenylketonuria (PKU) care. To develop the guidelines, we did a literature search, critical appraisal, and evidence grading according to the Scottish Intercollegiate Guidelines Network method. We used the Delphi method when little or no evidence was available. From the 70 recommendations formulated, in this Review we describe ten that we deem as having the highest priority. Diet is the cornerstone of treatment, although some patients can benefit from tetrahydrobiopterin (BH4). Untreated blood phenylalanine concentrations determine management of people with PKU. No intervention is required if the blood phenylalanine concentration is less than 360 mumol/L. Treatment is recommended up to the age of 12 years if the phenylalanine blood concentration is between 360 mumol/L and 600 mumol/L, and lifelong treatment is recommended if the concentration is more than 600 mumol/L. For women trying to conceive and during pregnancy (maternal PKU), untreated phenylalanine blood concentrations of more than 360 mumol/L need to be reduced. Treatment target concentrations are as follows: 120-360 mumol/L for individuals aged 0-12 years and for maternal PKU, and 120-600 mumol/L for non-pregnant individuals older than 12 years. Minimum requirements for the management and follow-up of patients with PKU are scheduled according to age, adherence to treatment, and clinical status. Nutritional, clinical, and biochemical follow-up is necessary for all patients, regardless of therapy.

International audience; Several genome-wide association studies (GWAS) have identified a strong association between serum vitamin B12 and fucosyltransferase 2 (FUT2), a gene associated with susceptibility to Helicobacter pylori infection. Hazra et al. conducted a meta-analysis of three GWAS and found three additional loci in MUT, CUBN and TCN1. Other GWAS conducted in Italy and China confirmed the association for FUT2 gene. Alpha-2-fucosyltransferase (FUT2) catalyzes fucose addition to form H-type antigens in exocrine secretions. FUT2 non-secretor variant produces no secretion of H-type antigens and is associated with high-plasma vitamin B12 levels. This association was explained by the influence of FUT2 on H. pylori, which is a risk factor of gastritis, a main cause of vitamin B12 impaired absorption. However, we recently showed that H. pylori serology had no influence on FUT2 association with vitamin B12, in a large sample population, suggesting the involvement of an alternative mechanism. GIF is another gene associated with plasma levels of vitamin B12 and gastric intrinsic factor (GIF) is a fucosylated protein needed for B12 absorption. Inherited GIF deficiency produces B12 deficiency unrelated with gastritis. We report 2 families with heterozygous GIF mutation, 290T>C, M97T, with decreased binding affinity of GIF for vitamin B12 and one family with heterozygous GIF mutation 435\₄37delGAA, K145_N146delinsN and no B12 binding activity of mutated GIF. All cases with vitamin B12 deficit carried the FUT2 rs601338 secretor variant. Ulex europeus binding to GIF was influenced by FUT2 genotypes and GIF concentration was lower, in gastric juice from control subjects with the secretor genotype. GIF290C allele was reported in 5 European cases and no Africans among 1282 ambulatory subjects and was associated with low plasma vitamin B12 and anaemia in the single case bearing the FUT2 secretor variant. We concluded that FUT2 secretor variant worsens B12 status in cases with heterozygous GIF mutations by impairing GIF secretion, independently from H. pylori-related gastritis.

International audience; BACKGROUND:Three international surveys were developed aiming to identify the current nutrition educational tools used in the management of phenylketonuria (PKU) and the perceived effectiveness of these tools by clinicians, parents and patients.METHODS:The first two surveys were distributed through the Metabolic Dietitians ListServe (pno-metabl@listserv.cc.emory.edu), and the third survey was distributed by international clinics and the National PKU Alliance website (www.npkua.org). A total of 888 responses (S1, n = 88; S2, n = 81; S3, n = 719) were collected from all three surveys. The surveys represent participants from 17 countries, in Europe; North America (USA and Canada); Mexico; Argentina; Turkey; Australia; and Africa (Tunisia).RESULTS:A consistent decline in 'parents as role models' as an educational tool was observed starting at age 10 years. Patients responded they feel their families are the most effective form of education, whereas handouts were selected as the least effective educational tool by patients. Parents responded they feel the most effective educational tool is one-on-one counselling. Patients and parents show a desirable trend in wanting to attend group clinic, even in centres where this type of educational tool is not offered.CONCLUSIONS:There was a discrepancy between clinicians and patient views regarding the perceived effectiveness of the nutrition education tools. Future research is needed surrounding the impact nutrition education may have on improved dietary compliance in patients with PKU.

International audience; PURPOSE:To determine whether patients' perception of early therapeutic alliance (TA) could predict time to achieve a target weight among adolescents undergoing treatment for anorexia nervosa.METHOD:TA was assessed in a prospective cohort recruited from both inpatient and outpatient settings by self-administered and validated questionnaires. Kaplan-Meier survival curves were compared by log rank test, and Cox regression was used to test whether patients' perception of early TA predicted time to achieve a target weight.RESULTS:In total, 108 patients were included, and 79.6% achieved a target weight. Better patient perception of early TA increased the hazard ratio (HR) of achieving a target weight (HR = 2.7, 95% confidence interval: 1.7-4.4, p < .001) such as being in the inpatient setting by 6.7. Being very severely underweight at admission decreased the HR of achieving the target weight.CONCLUSION:Patients' perception of early TA is a good predictor of achieving a target weight. Because TA is a modifiable construct, it could be a target for intervention.

For almost all patients with PKU, a low phenylalanine diet is the basis of the treatment despite a widely varying natural protein tolerance. A vitamin and mineral supplement is essential and it is commonly added to a phenylalanine-free (phe-free) source of L-amino acids. In PKU, many phe-free L-amino acid supplements have age-specific vitamin and mineral profiles to meet individual requirements. The main micronutrient sources are chemically derived and their delivery dosage is usually advised in three or more doses throughout the day. Within the EU, the composition of VM (vitamin and mineral) phe-free L-amino acid supplements is governed by the Foods for Special Medical Purposes (FSMP) directive (European Commission Directive number 1999/21/EC and amended by Directive 2006/141/EC). However the micronutrient composition of the majority fails to remain within FSMP micronutrient maximum limits per 100 kcal due to their low energy content and so compositional exceptions to the FSMP directive have to be granted for each supplement. All patients with PKU require an annual nutritional follow-up, until it has been proven that they are not at risk of any vitamin and mineral imbalances. When non-dietary treatments are used to either replace or act as an adjunct to diet therapy, the quality of micronutrient intake should still be considered important and monitored systematically. European guidelines are required about which micronutrients should be measured and the conditions (fasting status) for monitoring. (C) 2013 Elsevier Inc. All rights reserved.

Patients with phenylketonuria (PKU) encompass an 'at risk' group for micronutrient imbalances. Optimal nutrient status is challenging particularly when a substantial proportion of nutrient intake is from non-natural sources. In PKU patients following dietary treatment supplementation with micronutrients is a necessity and vitamins and minerals should either be added to supplement phenylalanine-free L-amino acids or given separately. In this literature review of papers published since 1990, the prevalence of vitamin and mineral deficiency is described, with reference to age of treatment commencement, type of treatment, dietary compliance, and dietary practices. Biological micronutrient inadequacies have been mainly reported for zinc, selenium, iron, vitamin B-12 and folate. The aetiology of these results and possible clinical and biological implications are discussed. In PKU there is not a simple relationship between the dietary intake and nutritional status, and there are many independent and interrelated complex factors that should be considered other than quantitative nutritional intake. (C) 2013 Elsevier Inc. All rights reserved.

International audience; In our phenylketonuria (PKU) cohort of 120 patients, we uncovered a couple of cases of undiagnosed mild phenylketonuria (mPKU)/hyperphenylalaninemia (mHPA) in maternal parents of the PKU cohort. This finding prompted us to evaluate the risk of either mild phenylketonuria or mild hyperphenylalaninemia in the parent population whose children were diagnosed with hyperphenylalaninemia (HPA). Taking into account the phenylalanine hydroxylase (PAH) mutation carrier frequency and the PAH mild mutation rate, we estimated that the prevalence of the parental mPKU/mHPA varied widely, from 1/74 in Turkey to 1/708 in Lithuania. The benefits of the parental detection procedure described here are the prevention of further maternal PKU syndrome, the follow-up of the newly detected patients and the accuracy of the genetic counseling provided to these families. This very simple procedure should be incorporated into neonatal PKU management of the hospitals in countries where a routine systematic neonatal screening is operational.

Background The efficacy and safety of intra-venous (i.v.) sodium benzoate for treating acute episodes of hyperammonemia in urea cycle enzyme disorders (UCD) is well known. However, published data do not provide a clear picture of the benefits and risks of this drug. We report a retrospective multicentre study on the use of i.v. sodium benzoate in patients treated for UCD between 2000 and 2010 in the 6 French reference centres for metabolic diseases. Results Sixty-one patients with UCDs - 22 ornithine transcarbamylase (20 confirmed, 2 suspected), 18 arginino-succinate synthetase, 15 carbamoyl phosphate synthetase, 3 arginosuccinate lyase, 1 arginase deficiency, 1 N-acetylglutamate synthetase, 1 HHH syndrome - required i.v. sodium benzoate over the course of 95 acute episodes (NH3 > 100 μmol/L or high-risk situations, i.e., gastroenteritis, surgery). Forty out of 61 patients experienced only one episode of decompensation (neonatal coma, 68.6 %). The most frequent cause of late decompensation was infection (55.5 %). A loading dose of i.v. sodium benzoate (median 250 mg/kg over 2 h) was administered for 41/95 acute episodes. The median maintenance dose was 246.1 mg/kg/day, administered via peripheral venous infusion in all cases except one via a central line. The total median duration of i.v. sodium benzoate treatment per episode was 2 days (0–13 days). The median durations of hospitalization in intensive care and metabolic units were 4 days (0–17 days) and 10 days (0–70 days), respectively. Eight patients died during the neonatal coma (n = 6) or surgery (n = 2). The median plasma ammonium level before treatment was 245.5 μmol/L (20.0–2274.0 μmol/L); it decreased to 40.0 μmol/L in patients who were alive (13.0–181.0 μmol/L) at the end of treatment with i.v. sodium benzoate. A decrease in ammonium level to ≤ 100 μmol/L was obtained in 92.8 % of episodes (64/69 of the episodes recorded for the 53 surviving patients). Five patients required another treatment for hyperammonemia (sodium phenylacetate + sodium benzoate, haemofiltration). Eighteen side effects were reported related to the i.v. infusion (local diffusion, oedema). Conclusion This 10-year retrospective study shows that i.v. sodium benzoate associated with an emergency regimen is an effective and safe treatment for acute episodes of UCD.

International audience; Peroxisome biogenesis disorders (PBD) are a heterogeneous group of disorders due to PEX genesmutations, with a broad clinical spectrum comprising severe neonatal disease to mild presentation. Recently, Berendse et al reported an improvement of peroxisomal functions with L-arginine supplementation in fibroblasts with specific mutations of PEX1, PEX6, and PEX12. We report the first treatment by L-arginine in a patient homozygous for the specific PEX12 mutation shown to be L-arginine responsive in fibroblasts. We described the effect of L-arginine on biochemical (decrease of some plasma peroxisomal parameters) and neurophysiological (improvement of deafness) parameters. Some subjective clinical effects have also been observed (no more sialorrhea, behavior improvement). More studies are needed to assess the efficacy of L-arginine in some PBD patients with specific mutations.

National audience

Background Deficient nucleotide excision repair (NER) activity causes a variety of autosomal recessive diseases including xeroderma pigmentosum (XP) a disorder which pre-disposes to skin cancer, and the severe multisystem condition known as Cockayne syndrome (CS). In view of the clinical overlap between NER-related disorders, as well as the existence of multiple phenotypes and the numerous genes involved, we developed a new diagnostic approach based on the enrichment of 16 NER-related genes by multiplex amplification coupled with next-generation sequencing (NGS). Methods Our test cohort consisted of 11 DNA samples, all with known mutations and/or non pathogenic SNPs in two of the tested genes. We then used the same technique to analyse samples from a prospective cohort of 40 patients. Multiplex amplification and sequencing were performed using AmpliSeq protocol on the Ion Torrent PGM (Life Technologies). Results We identified causative mutations in 17 out of the 40 patients (43 %). Four patients showed biallelic mutations in the ERCC6(CSB) gene, five in the ERCC8(CSA) gene: most of them had classical CS features but some had very mild and incomplete phenotypes. A small cohort of 4 unrelated classic XP patients from the Basque country (Northern Spain) revealed a common splicing mutation in POLH (XP-variant), demonstrating a new founder effect in this population. Interestingly, our results also found ERCC2(XPD), ERCC3(XPB) or ERCC5(XPG) mutations in two cases of UV-sensitive syndrome and in two cases with mixed XP/CS phenotypes. Conclusions Our study confirms that NGS is an efficient technique for the analysis of NER-related disorders on a molecular level. It is particularly useful for phenotypes with combined features or unusually mild symptoms. Targeted NGS used in conjunction with DNA repair functional tests and precise clinical evaluation permits rapid and cost-effective diagnosis in patients with NER-defects. Electronic supplementary material The online version of this article (doi:10.1186/s13023-016-0408-0) contains supplementary material, which is available to authorized users.

MCAD deficiency is the most common fatty acid oxidation disorder, with the prevalence varying from 1/10,000 to 1/27,000 in the countries adjacent to France. As the High Authority for Health has recently proposed including MCAD deficiency in the panel of diseases neonatally screened for in France, a consensus was written for the management of MCAD deficiency diagnosed either clinically or by neonatal screening. Patients may present acutely with hyperammonemia, hypoglycemia, encephalopathy, and hepatomegaly, mainly after a prolonged fast of intercurrent infection. Sudden death related to heartbeat disorders may also occur. The diagnosis of MCAD deficiency is suspected on the plasma acylcarnitine and/or the urinary organic acid profile. The diagnosis is confirmed by molecular biology and the enzymatic activity for patients who are not homozygous for the main mutation c.985A>G. However, some MCAD-deficient individuals may remain asymptomatic throughout life. The mainstay of treatment consists in avoiding prolonged fast and prescribing l-carnitine for patients who exhibit a deficiency in plasma carnitine. This management has radically modified the natural history of MCAD deficiency. This consensus will allow homogeneous management of these patients once the neonatal screening of MCAD deficiency has been introduced in France.

Common inborn errors of metabolism treated by low natural protein diets [amino acid (AA) disorders, organic acidemias and urea cycle disorders] are responsible for a collection of diverse clinical symptoms, each condition presenting at different ages with variable severity. Precursor-free or essential l-AAs are important in all these conditions. Optimal long-term outcome depends on early diagnosis and good metabolic control, but because of the rarity and severity of conditions, randomized controlled trials are scarce. In all of these disorders, it is commonly described that dietary adherence deteriorates from the age of 10 years onwards, at least in part representing the transition of responsibility from the principal caregivers to the patients. However, patients may have particular difficulties in managing the complexity of their treatment because of the impact of the condition on their neuropsychological profile. There are little data about their ability to self-manage their own diet or the success of any formal educational programs that may have been implemented. Trials conducted in non-phenylketonuria (PKU) patients are rare, and the development of specialist l-AAs for non-PKU AA disorders has usually shadowed that of PKU. There remains much work to be done in refining dietary treatments for all conditions and gaining acceptable dietary adherence and concordance, which is crucial for an optimal outcome.

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Background Deficiency of mitochondrial trifunctional protein (MTP) is caused by mutations in the HADHA and HADHB genes, which have been mostly delineated at the genomic DNA level and have not been always elucidated. Aim To identify mutations in a French cohort of 52 MTP deficient patients and the susceptibility of mutations generating premature termination codons (PTCs) to the nonsense mRNA mediated decay (NMD). Methods Mutation screening in fibroblasts was performed at the cDNA level and real-time RT-PCR was used to compare the levels of the different PTC-bearing mRNAs before and after a treatment of fibroblasts by emetine, a translation inhibitor. Results A mutation detection rate of 100% was achieved. A total of 22 novel mutations were identified, including a large-sized genomic deletion in HADHB gene. A high proportion of all identified mutations were non-sense, frameshift and splicing mutations, generating (PTCs), distributed essentially on HADHA coding regions. We could demonstrate that the majority of mutations resulting in PTCs conform to the established rules governing the susceptibility to NMD. Conclusion Our results emphasize the value of cDNA analysis in the characterization of HADHA and HADHB mutations and further strengthen the model of haploinsufficiency as a major pathomechanism in MTP defects.

Sanfilippo syndrome, or mucopolysaccharidosis type III (MPSIII) is a lysosomal storage disease with predominant neurological manifestations in affected children. It is considered heterogeneous with respect to prevalence, clinical presentation, biochemistry (four biochemical forms of the disease referred to as MPSIIIA, B, C, and D are known), and causative mutations. The perspective of therapeutic options emphasizes the need for better knowledge of MPSIII incidence and natural history. We performed parallel retrospective epidemiological studies of patients diagnosed with MSPIII in France (n = 128), UK (n = 126), and Greece (n = 20) from 1990 to 2006. Incidences ranged from 0.68 per 100,000 live-births in France to 1.21 per 100,000 live-births in UK. MPSIIIA, which predominates in France and UK, was absent in Greece, where most patients have MPSIIIB. The study confirmed the large allelic heterogeneity of MPSIIIA and MPSIIIB and detected several yet undescribed mutations. Analysis of clinical manifestations at diagnosis and over a 6–7 years follow-up indicated that almost all patients, whatever the disease subtype, expressed neurological manifestations before the age of 5 years, including language acquisition delay, cognitive delay, and/or abnormal behavior. In contrast to relatively homogeneous early onset manifestations, disease progression showed significant variation depending on subtype and age at diagnosis. Different severities of disease progressions and different allele distribution between France and UK suggested that mutations are not equally deleterious, although genotype–phenotype correlation could not be established. Notwithstanding the rapidity of further clinical deterioration, all MPSIII patients suffer early onset devastating neurological manifestations that deserve early treatment when available. © 2010 Wiley-Liss, Inc.

La phenylcetonurie (PCU) est la maladie hereditaire du metabolisme la plus frequente. Elle se transmet sur le mode autosomique recessif et est liee a un deficit enzymatique entrainant l’accumulation de phenylalanine dans l’organisme, notamment au niveau cerebral. Non traitee, elle entraine des troubles neurologiques graves et irreversibles (deficience intellectuelle, etc.). Le devenir des patients atteints de phenylcetonurie a ete transforme par le depistage neonatal systematique. En effet, le traitement, fonde sur la mise en place precoce et continue d’un regime alimentaire pauvre en phenylalanine, garantit a ces enfants un devenir cognitif normal. Cependant, des contradictions emergent de la litterature, certaines etudes suggerant des difficultes cognitives (executives). Nous avons etudie le profil neuropsychologique de 33 patients (enfants, adolescents et adultes), depistes depuis la naissance et suivis regulierement au niveau medical. Les resultats montrent que ces patients ont effectivement de bonnes capacites cognitives, malgre une faiblesse executive, notamment chez les adolescents « non compliants » au regime. Cette etude appuie ainsi l’interet d’une evaluation neuropsychologique comprenant une evaluation de l’efficience intellectuelle, mais aussi plus specifiquement une evaluation des fonctions executives, notamment au moment de l’adolescence ou les risques de non-compliance sont accrus.

Despite recent advances in the management of phenylketonuria and hyperphenylalaninemia, important questions on the management of this disorder remain unanswered. Consensus exists on the need for neonatal screening and early treatment, yet disagreement persists over threshold levels of blood phenylalanine for starting treatment, target blood phenylalanine levels, and the management of older patient groups. The mainstay of treatment is a phenylalanine-restricted diet, but its application varies between and within countries. Beyond diet treatment, there is a lack of consensus on the use of newer treatments such as tetrahydrobiopterin. Although neonatal screening and early treatment has meant that most well-treated children grow up with near-normal IQ scores, the effect of relaxing metabolic control on cognitive and executive function later in life is still not fully understood. Although it is clear from the available literature that the active control of blood phenylalanine levels is of vital importance, there are other treatment-related factors that affect outcome. A uniform and firmly evidence-based approach to the management of phenylketonuria is required. Pediatrics 2010;126:333-341

Tay-Sachs disease (TSD) is a recessively inherited neurodegenerative disorder due to mutations in the HEXA gene resulting in a beta-hexosaminidase A (Hex A) deficiency. The purpose of this study was to characterize the molecular abnormalities in patients with infantile or later-onset forms of the disease. The complete sequencing of the 14 exons and flanking regions of the HEXA gene was performed with a unique technical condition in 10 unrelated TSD patients. Eleven mutations were identified, including five splice mutations, one insertion, two deletions and three single-base substitutions. Four mutations were novel: two splice mutations (IVS8+5G>A, IVS2+4delAGTA), one missense mutation in exon 6 (c.621T>G (p.D207E)) and one small deletion (c.1211-1212delTG) in exon 11 resulting in a premature stop codon at residue 429. The c.621T>G missense mutation was found in a patient presenting an infantile form. Its putative role in the pathogenesis of TSD is suspected as residue 207 is highly conserved in human, mouse and rat. Moreover, structural modelling predicted changes likely to affect substrate binding and catalytic activity of the enzyme. The time-saving procedure reported here could be useful for the characterization of Tay-Sachs-causing mutations, in particular in non-Ashkenazi patients mainly exhibiting rare mutations.

La litterature fait etat d’un risque de perturbation des fonctions executives (FE) chez les enfants atteints de phenylcetonurie depistes et traites precocement (PCU-TP). Neanmoins, ces resultats restent controverses a plusieurs niveaux (nature, severite, specificite). Dans ce contexte, cet article propose une revue critique et actualisee de la litterature portant sur l’hypothese dysexecutive dans la phenylcetonurie. La premiere partie synthetise la methodologie et les resultats des 42 etudes recensees, sous forme inedite d’un tableau. L’ensemble des articles est analyse sous l’angle original des modeles integratifs developpementaux des FE et des considerations methodologiques actuelles. La seconde partie amene une prospective de recherche visant a promouvoir l’interet d’une evaluation exhaustive et theoriquement guidee du fonctionnement executif. Le caractere pluriel et interdependant des processus executifs justifie d’utiliser diverses mesures impliquant les differentes facettes des FE. Il apparait egalement important de determiner les relations qu’entretiennent les FE avec d’autres concepts comme la vitesse de traitement, dans une perspective developpementale. Enfin, la comprehension des difficultes executives impliquera de passer par une analyse de leurs repercussions au quotidien. L’ensemble de ces considerations conditionne la problematique du reperage et de l’evaluation des FE chez l’enfant PCU-TP, prealables necessaires a une meilleure comprehension du phenotype neuropsychologique de la maladie.

Control of blood phenylalanine (Phe) levels throughout the life of a person diagnosed with phenylketonuria (PKU) is the biochemical management strategy necessary to provide the best potential for optimal outcome. Psychosocial support mechanisms comprise the other aspects of PKU management that are necessary to overcome the hurdles of living with this chronic disease and to adhere to the rigors of its management. Additional psychosocial support may be required, in light of increasing evidence that control of blood Phe levels in PKU can still lead to subtle but measurable cognitive function deficits as well as a predisposition to certain psychiatric symptoms and disorders. An all encompassing PKU management strategy that goes beyond simply treating blood Phe levels can empower and enable people born with PKU to achieve similar life goals as those born without PKU. This review looks at PKU management strategies that go beyond treating Phe levels, specifically (1) the roles psychologists play in managing PKU from infancy through adulthood and how they help PKU families and caregivers deal with the disease and the burden of its management; (2) understanding the challenges of transitioning into adulthood as an individual with PKU and addressing unmet needs in this population; (3) how non-traditional practices can be utilized in PKU. The objective is to emphasize that management of PKU goes well beyond addressing the biochemical nature of this disease in order to achieve optimal patient outcomes.

Objective. The purpose of this series was to evaluate the value of contrast-enhanced ultrasonography (CEUS) in the characterization of focal liver lesions (FLLs) in patients with glycogen storage diseases (GSDs). Methods. Contrast-enhanced ultrasonographic data obtained for characterization of 8 FLLs (size, 0.9–10.2 cm) in 2 patients with GSD type Ia (GSD-Ia) and lesion growth or recurrent abdominal pain were reviewed and compared with computed tomographic (CT) and magnetic resonance imaging (MRI) data. After total and left hepatectomy, pathologic examination confirmed benign adenomas in 6 of the evaluated lesions. Follow-up confirmed benignity in the 2 remaining lesions. Results. In all FLLs, CEUS showed marked hypervascularity in the early arterial phase. Centripetal filling was shown in only 1 lesion, and diffuse enhancement without any clear direction was shown in all other lesions. During the portal and late phases, 6 of the 8 lesions showed sustained enhancement, including 2 lesions that appeared heterogeneous during all phases of CT and MRI. In an aspect of 1 of these 6 large adenomas, late wash-out could be explained by sinusoid compression. The other 2 adenomas showed moderate wash-out but remained homogeneous. Conclusions. Focal liver lesions found in patients with GSD-Ia have similar patterns on CEUS compared with incidental adenomas. Global or partial hypoenhancement observed in the late phase did not indicate a transition to hepatocellular carcinoma but may have been related to ischemia. Key words: glycogen storage disease; hepatocellular adenomas; imaging; liver; ultrasonographic contrast agents.

Glutaric aciduria type 1 (GA1) is an autosomal recessive neurometabolic disorder due to glutaryl CoA dehydrogenase deficiency. Comprehensive descriptions of GA1-associated movement disorders are rare. In order to refine the description of the motor phenotype, we prospectively studied 16 consecutive pediatric and adult GA1 patients, focusing on the movement disorders and their time course. In most patients, generalized dystonia, superimposed on baseline axial hypotonia, remained the predominant feature throughout the disease course. With aging, it tended to evolve from mobile to fixed dystonia and to be associated with akinetic-rigid parkinsonism. Prominent orofacial involvement was a consistent feature in GA1 patients with movement disorders, resulting in speech disorders with features of combined hyperkinetic dysarthria and speech apraxia. The types and outcome of movement disorders in this setting should be taken into consideration during rehabilitation and for patient selection and evaluation in therapeutic trials. © 2008 Movement Disorder Society

The outcome in phenylketonuria is related to the early diagnosis and management due to neonatal screening.To assess the interest of tetrahydrobiopterin (BH4) loading test and phenylalanine hydroxylase (PAH) genotyping in the management of neonates with hyperphenylalaninemia (HPA).We evaluate the effectiveness of a BH4 loading test (20 mg/kg) in ten neonates screened for HPA. We evaluated the time required to reach a target plasma Phenylalanine (Phe) level below 300 micromol/l. We compared these ten BH4-loaded patients to the 10 previous neonates non-loaded with BH4. In all these patients, the PAH genotype was determined.One loaded patient had biopterin synthesis deficiency and has been retrieved from statistical analysis. All others patients have PAH deficiency. Between the BH4 loaded group (L) and the BH4 non-loaded group (NL), a statistically significant difference was observed in the average time required to reached the target Phe level (13.56 +/- 4.30 (L) vs. 20.6 +/- 7.59 days (NL) [p0.02]). Results of the genotyping from all but one of these 19 patients indicated that among all mutations present in this patient population, there were 4 known PAH mutations associated with BH4 responsiveness (p.R261Q, the p.V388 M, the p.E390G and the p.Y414C). These mutations were found in 4 non-loaded and 6 loaded patients. Two patients had a more than 90% reduction in their plasma Phe level within 24 h after the load. One of these patients had a PTPS deficiency. The other fully responsive patient (p.Y414C and IVS10-11GA) has been treated with BH4 from birth with an excellent metabolic control for three years now.BH4 loading test improves the management of HPA. It allows an immediate identification of the children fully responsive to BH4. Our results therefore suggest the incorporation of BH4 loading test in the management of neonates screened for HPA.

Resume L’hypervitaminose A est une cause rare d’hypercalcemie chez l’enfant. Son mode de survenue peut etre surprenant comme dans l’observation rapportee. Observation Un garcon de trois ans, presentant d’importants troubles du comportement, a ete hospitalise en raison d’une alteration de l’etat general associee a des vomissements, des cephalees, de la fievre et des anomalies cutanees. Une hypercalcemie a 168 mg/L a ete retrouvee. La seule etiologie etait une prise aberrante de vitamine A dans le cadre d’un regime « autistique » : 100 000 UI/j pendant trois mois, puis 150 000 UI/j les trois mois suivants. L’intoxication a ete confirmee par les dosages plasmatiques de vitamine A, par l’augmentation du rapport molaire de vitamine A sur RBP et par la presence de palmitate de retinol plasmatique. Un traitement en urgence par rehydratation, biphosphonates et furosemide, a permis une normalisation efficace de la calcemie. Conclusion Devant toute hypercalcemie de cause non evidente, un interrogatoire rigoureux doit rechercher une intoxication a la vitamine A. Notre observation illustre le danger de certains regimes proposes chez les enfants autistiques.

This study aimed to evaluate the response to and safety of an 8-day course of sapropterin dihydrochloride (6R-tetrahydrobiopterin or 6R-BH4) 10 mg/kg per day in patients with phenylketonuria (PKU), who have elevated blood phenylalanine (Phe) levels, and to identify a suitable cohort of patients who would respond to sapropterin dihydrochloride treatment with a reduction in blood Phe level. Eligible patients were agedor = 8 years, had blood Phe levelsor = 450 micromol/L and were not adhering to a Phe-restricted diet. Suitable patients were identified by aor = 30% reduction in blood Phe level from baseline to day 8 following sapropterin dihydrochloride treatment. The proportion of patients who met these criteria was calculated for the overall population and by baseline Phe level (600, 600 to900, 900 to1200 andor = 1200 micromol/L). In total, 485/490 patients completed the study and 20% (96/485) were identified as patients who would respond to sapropterin dihydrochloride. A reduction in Phe level was observed in all subgroups, although response was greater in patients with lower baseline Phe levels. Wide variability in response was seen across all baseline Phe subgroups. The majority of adverse events were mild and all resolved without complications. Sapropterin dihydrochloride was well tolerated and reduced blood Phe levels across all PKU phenotypes tested. Variability in reduction of Phe indicates that the response to sapropterin dihydrochloride cannot be predicted by baseline Phe level.

BackgroundLysosomal acid lipase is an essential lipid-metabolizing enzyme that breaks down endocytosed lipid particles and regulates lipid metabolism. We conducted a phase 3 trial of enzyme-replacement therapy in children and adults with lysosomal acid lipase deficiency, an underappreciated cause of cirrhosis and severe dyslipidemia. MethodsIn this multicenter, randomized, double-blind, placebo-controlled study involving 66 patients, we evaluated the safety and effectiveness of enzyme-replacement therapy with sebelipase alfa (administered intravenously at a dose of 1 mg per kilogram of body weight every other week); the placebo-controlled phase of the study was 20 weeks long and was followed by open-label treatment for all patients. The primary end point was normalization of the alanine aminotransferase level. Secondary end points included additional disease-related efficacy assessments, safety, and side-effect profile. ResultsSubstantial disease burden at baseline included a very high level of low-densit...

International audience; Background In phenylketonuria, genetic heterogeneity, frequent compound heterozygosity, and the lack of functional data for phenylalanine hydroxylase genotypes hamper reliable phenotype prediction and individualised treatment.Methods A literature search revealed 690 different phenylalanine hydroxylase genotypes in 3066 phenylketonuria patients from Europe and the Middle East. We determined phenylalanine hydroxylase function of 30 frequent homozygous and compound heterozygous genotypes covering 55% of the study population, generated activity landscapes, and assessed the phenylalanine hydroxylase working range in the metabolic (phenylalanine) and therapeutic (tetrahydrobiopterin) space.Results Shared patterns in genotype-specific functional landscapes were linked to biochemical and pharmacological phenotypes, where (1) residual activity below 3.5% was associated with classical phenylketonuria unresponsive to pharmacological treatment; (2) lack of defined peak activity induced loss of response to tetrahydrobiopterin; (3) a higher cofactor need was linked to inconsistent clinical phenotypes and low rates of tetrahydrobiopterin response; and (4) residual activity above 5%, a defined peak of activity, and a normal cofactor need were associated with pharmacologically treatable mild phenotypes. In addition, we provide a web application for retrieving country-specific information on genotypes and genotype-specific phenylalanine hydroxylase function that warrants continuous extension, updates, and research on demand.Conclusions The combination of genotype-specific functional analyses with biochemical, clinical, and therapeutic data of individual patients may serve as a powerful tool to enable phenotype prediction and to establish personalised medicine strategies for dietary regimens and pharmacological treatment in phenylketonuria.

Sapropterin dihydrochloride (Kuvan(®)), a synthetic 6R-diastereoisomer of tetrahydrobiopterin (BH4), is approved in Europe for the treatment of patients aged ≥4 years with hyperphenylalaninaemia (HPA) due to BH4-responsive phenylalanine hydroxylase (PAH) deficiency, in conjunction with a phenylalanine-restricted diet, and also for the treatment of patients with BH4 deficiency.KAMPER is an ongoing, observational, multicentre registry with the primary objective of providing information over 15 years on long-term safety of sapropterin dihydrochloride treatment in patients with HPA. Here we report initial data on characteristics from patients recruited by the time of the third interim analysis and results at 1 year.Overall, 325 patients from 55 sites in seven European countries were included in the analysis: 296 (91.1%) patients with PAH deficiency (median [Q1, Q3] age, 10.3 [7.2, 15.0] years) and 29 (8.9%) with BH4 deficiency (12.8 [6.6, 18.9] years). Fifty-nine patients (18.2%) were aged ≥18 years; 4 patients were pregnant. No elderly patients (aged ≥65 years) or patients with renal or hepatic insufficiency were enroled in the study. Twelve-month data were available for 164 patients with PAH deficiency and 16 with BH4 deficiency. No new safety concerns were identified as of May 2013.Initial data from KAMPER show that sapropterin dihydrochloride has a favourable safety profile. Registry data collected over time will provide insight into the management and outcomes of patients with PAH deficiency and BH4 deficiency, including long-term safety, impact on growth and neurocognitive outcomes and the effect of sapropterin dihydrochloride treatment on populations of special interest.

International audience; Phenylketonuria (PKU) is no longer considered merely a pediatric concern; current guidelines recommend life-long treatment. However, information on the adult PKU patient population is scarce. A survey was initiated on behalf of the European PKU Group (EPG) that focused specifically on early-treated adult patients diagnosed by neonatal screening. The online survey was sent via email to 204 healthcare professionals (HCPs) in 33 countries. Eighty-one HCPs from 24 countries responded. The main findings were that the majority of adult patients with PKU in active follow-up are under 30 years of age and are managed in centers that also treat children. Seventy-eight percent of adult PKU patients in follow-up receive treatment, mainly by diet (71 %), with BH4 treatment rarely used in adulthood. Only 26 % of responding HCPs perform routine neurocognitive testing in all their adult patients. There was little consensus regarding target blood phenylalanine (Phe) concentrations, although the majority of respondents reported that their patients achieved blood Phe concentrations below 1200 mu mol/l.Conclusion: This survey highlights the need for blood Phe concentration target recommendations and consensus guidelines, more research into adult PKU patient management, and the need to identify those patients lost to follow-up to ensure PKU is managed for life.

Resume Cette revue generale souligne l'importance d'une prise en charge nutritionnelle structuree des troubles du comportement alimentaire de l'adolescent, en particulier de l'anorexie mentale, ses bases physiopathologiques, son influence sur les pronostics a court et a long terme. Les consequences somatiques mais aussi neuropsychologiques de la denutrition, ses consequences en termes de morbidite, de mortalite et de sequelles sont soulignees. Les modalites de la renutrition, en ville et a l'hopital, l'importance de la notion de « poids cible » a atteindre et du maintien de ce poids dans les mois et les annees qui suivent en raison de la frequence encore trop importante des rechutes (50 %) sont developpees, de meme que la necessite d'une « alliance therapeutique » avec la famille et, des que possible, avec la malade et l'interet d'une collaboration etroite entre les equipes psychiatrique et pediatrique. Ils discutent plus brievement des aspects nutritionnels du traitement de la boulimie. Dans leur conclusion, les auteurs font etat de leurs resultats sur une cohorte de 161 malades dont le devenir est connu avec un recul de plus de quatre ans et dont 144 ont participe a une evaluation selon des modalites validees (68 % de bons resultats, 23,3 % de resultats moyens, 8,7 % de resultats mediocres) temoignant d'une progression sur des resultats anterieurs et plus satisfaisants que ceux de deux autres etudes utilisant des methodes d'evaluation similaires et publiees en 1991 et 2001.

Phenylketonuria (PKU) is an inherited metabolic disease affecting about one birth out of 15 000. From 1978, a national systematic neonatal screening was set up in France with a regional organisation. French rational and guidelines have been established by the national PKU group with the collaboration of all the physicians responsible for the regional centres. These guidelines specify the minimal diagnosis procedures leading to an optimal treatment of all patients. A low-phenylalanine diet must be started as soon as possible in the neonatal period for all newborns whose phenylalanine levels are above 10 mg/dl. The dietary control must keep the phenylalanine plasma levels between 2 and 5 mg/dl until 10 years of age. After this age, several data argue for a progressive and controlled relaxation of the diet, keeping the phenylalanine level below 15 mg/dl until the end of the adolescence and below 20 to 25 mg/dl in adulthood. All PKU patients must be followed up for life, in order to screen those who may not bear the diet relaxation and in order to strictly prevent maternal PKU deleterious consequences.

L-asparaginase has been an important agent of acute lymphoblastic leukemia (ALL) therapy for more than 40 years. The major adverse events of L-asparaginase are immunoallergic reaction, pancreatitis, liver cytolysis (increased ASAT, ALAT, and bilirubin), and cerebral haemorrhage or thrombosis. Hyperammonemia has already been described with L -asparaginase treatment [1]. In the present article, we report acute metabolic encephalopathy in two young boys receiving asparaginase for B ALL relapse. We discuss the pathophysiology of this metabolic encephalopathy with hyperammonemia and its medical management.

International audience; Sapropterin dihydrochloride (SD) is the first drug treatment for phenylketonuria (PKU), but due to the lack of data, its use in maternal PKU must be undertaken with caution as noted in the FDA and EMEA labels. We collected data from eight pregnancies in PKU women treated with SD and we analysed the phenotypes of these patients, their tetrahydrobiopterin (BH4) responsiveness, the indications for SD treatment, the efficacy (metabolic control, phenylalanine (Phe) tolerance and offspring outcome) and the safety data. Results showed that in the seven patients known to be responsive to BH4, the use of SD during pregnancy was efficient in terms of metabolic control and Phe tolerance. The indications for giving SD included the failure of the low-Phe diet (n = 3), the fact that some of these women had never experienced the low Phe diet (n = 2), one unexpected pregnancy in a woman currently on SD and one pregnancy where the foetus was known to have PKU. The offspring of these seven pregnancies were all normal babies with normal birth measurements and outcomes. No side effect related to SD was observed in these seven cases. In the eighth case, SD was prescribed as a rescue treatment without previous knowledge of the BH4 responsiveness to a woman who was already 8 weeks pregnant without diet. The birth occurred at 33 weeks of gestational age with Potter syndrome (probably related to the absence of metabolic control during the first trimester) and the baby died in the first hours of life. In conclusion, the data presented here provides the first evidence that treatment with pharmacological doses of SD appears to be efficient and safe in women with PKU during pregnancy. Its use should, however, be restricted to those women previously identified to be clear responders to BH4.

International audience; Respiratory chain deficiencies exhibit a wide variety of clinical phenotypes resulting from defective mitochondrial energy production through oxidative phosphorylation. These defects can be caused by either mutations in the mtDNA or mutations in nuclear genes coding for mitochondrial proteins. The underlying pathomechanisms can affect numerous pathways involved in mitochondrial physiology. By whole-exome and candidate gene sequencing, we identified 11 individuals from 9 families carrying compound heterozygous or homozygous mutations in GTPBP3, encoding the mitochondrial GTP-binding protein 3. Affected individuals from eight out of nine families presented with combined respiratory chain complex deficiencies in skeletal muscle. Mutations in GTPBP3 are associated with a severe mitochondrial translation defect, consistent with the predicted function of the protein in catalyzing the formation of 5-taurinomethyluridine (τm(5)U) in the anticodon wobble position of five mitochondrial tRNAs. All case subjects presented with lactic acidosis and nine developed hypertrophic cardiomyopathy. In contrast to individuals with mutations in MTO1, the protein product of which is predicted to participate in the generation of the same modification, most individuals with GTPBP3 mutations developed neurological symptoms and MRI involvement of thalamus, putamen, and brainstem resembling Leigh syndrome. Our study of a mitochondrial translation disorder points toward the importance of posttranscriptional modification of mitochondrial tRNAs for proper mitochondrial function.

International audience; L-2-hydroxyglutaric aciduria is a rare genetic neurometabolic disease. It occurs in childhood with mental retardation, cerebellar ataxia, and epilepsy. Macrocephaly is present in half of the cases. Diagnosis is based on clinical symptoms, biological and radiological findings, and molecular testing. Specific treatments can improve the spontaneous progression of the disease. We examined two independent patients who presented with L-2-hydroxyglutaric aciduria. Clinical presentation led to cerebral MRI and urinary organic acid chromatography. The genetic analysis confirmed the diagnosis. Under specific treatment, the progression of the disease was subsequently stopped. L-2-hydroxyglutaric aciduria shares common symptoms with other genetic and metabolic diseases. However, the association of a distinct phenotype and typical MRI abnormalities (such as a high signal in the subcortical white matter, pallidum, and dentate nuclei) should draw the clinician's attention to this diagnosis. It can easily be suspected with a simple urinary analysis and can then be confirmed by genetic testing. With this case report, we show the importance of genetic identification to begin treatment with riboflavin. Early detection of L-2-hydroxyglutaric aciduria based on MRI abnormalities can enable rapid initiation of treatment and prevent disease progression.

During intercurrent illness children with methylmalonic acidemia were found to have increased resting energy expenditure (REE). We measured REE in children with disorders of propionate metabolism (methylmalonic and propionic acidemia) when they were well and compared the values with those predicted by the Schofield equation.Prospective study in tertiary care facility. REE was measured with open-circuit indirect calorimetry under standardized conditions. Predicted REE values were calculated with the Schofield equation. Fourteen subjects with propionic acidemia (n = 3) and methylmalonic acidemia (n = 11) were studied.The median REE was 690 kcal/d (range 186 to 1687 kcal/d), which is significantly reduced, representing 80% +/- 18% of that predicted by the Schofield height and weight equation (P.01). REE was significantly lower in female compared with male patients for unknown reasons. There were no differences with age or neurologic state. REE was not further reduced in those with chronic renal failure.REE in patients with disorders of propionate metabolism is reduced when they are well.

Normal or high levels of cholesterol have been measured in patients with anorexia nervosa (AN). Given that cholesterol intake in AN is usually very low, the reasons for this anomaly are not clearly understood. We studied lipid and lipoprotein profiles and endogenous cholesterol synthesis, estimated by serum lathosterol, in a population of 14 girls with AN, before and during a period of 30 days refeeding. The initial body mass index (BMI) of the patients was 13.41±1.62 kg/m 2 . No changes were observed during refeeding in endocrine parameters (ACTH, cortisol and estradiol). At Day 0 the lipids data measured here showed normal levels of triglycerides, and total cholesterol at the upper limits of the normal range (5.44±1 mmol/l). At this time, total and LDL cholesterol were negatively correlated with transthyretin and BMI. Serum lathosterol (a precursor in cholesterol synthesis pathway) increased significantly (5.99±1.75 (Day 0) vs. 8.39±2.96 (Day 30); P =0.02) while there was a significant decrease in apo B (0.79±0.33 (Day 0) vs. 0.60±0.17 g/l (Day 30), P =0.02) with refeeding. Thus, patients with initial high cholesterol levels have the worst nutritional status and high cholesterol levels are not related to a de novo synthesis. This profile returns to normal with refeeding. An increase of cellular cholesterol uptake may be responsible for this apparently paradoxical evolution with increase of cholesterol synthesis and decrease of apo B during renutrition.

We describe an assay which determines simultaneously riboflavin (RF), flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) in plasma, using galactoflavin (GF) as an internal standard. The flavins were extracted on a C18 Sep-Pack cartridge after protein precipitation with 10% trichloroacetic acid, and were analyzed on a C18 RP-HPLC with 85% phosphate-magnesium acetate buffer (pH 3.4) and 15% acetonitrile. FAD, FMN, GF and RF extraction recoveries were 101.0-5.6, 97.0-6.5, 97.0-2.0 and 95.0-4.1%, and reproducibilities were 5.9, 6.8, 2.1 and 4.3%, respectively. FAD, FMN and RF values in infant and adolescent plasma were in the range 53.5-108.2, 9.0-25.1 and 12.7-53.4 nM, and 36.5-157.20, 7.1-24.6 and 8.2-57.8 nM, respectively. Using GF as an internal standard improved the quantification of these B2 vitamers.

Hyperphenylalaninemia (HPA) is the most frequently inherited disorder of amino acid metabolism (prevalence 1:10,000). In France, a nationwide neonatal screening was organized in 1978 to control its efficacy and patient follow-up. Phenylketonuria (PKU) was diagnosed in 81.6% of screened patients, the remaining affected with either non-PKU HPA (17.2%) or with cofactor deficiency (1.1%). French guidelines were established to specify the minimal diagnosis procedures and optimal treatment of patients. A low-phenylalanine diet must be started within the first days of life for all newborns whose blood phenylalanine levels are above 10 mg/dL (600 micromol/L). The dietary control must keep the phenylalanine levels between 2 and 5 mg/dL (120 and 300 micromol/L) until 10 y of age. Thereafter, a progressive and controlled relaxation of the diet is allowed, keeping levels below 15 mg/dL until the end of adolescence and below 20 mg/dL (1200 micromol/L) in adulthood. A lifelong follow-up is recommended for PKU women to prevent for maternal PKU.

International audience; The cblG and cblC disorders of cobalamin (Cbl) metabolism are two inherited causes of megaloblastic anaemia. In cblG, mutations in methionine synthase (MTR) decrease conversion of hydroxocobalamin (HOCbl) to methylcobalamin, while in cblC, mutations in MMACHC disrupt formation of cob(II)alamin (detected as HOCbl). Cases with undetectable methionine synthase (MS) activity are extremely rare and classified as 'cblG-variant'. In four 'cblG-variant' cases, we observed a decreased conversion of cyanocobalamin to HOCbl that is also seen in cblC cases. To explore this observation, we studied the gene defects, splicing products and expression of MS, as well as MS/MMACHC protein interactions in cblG-variant, cblG, cblC and control fibroblasts. We observed a full-size MS encoded by MTR-001 and a 124 kDa truncated MS encoded by MTR-201 in cblG, cblC, control fibroblasts and HEK cells, but only the MTR-201 transcript and inactive truncated MS in cblG-variant cells. Co-immunoprecipitation and proximity ligation assay showed interaction between truncated MS and MMACHC in cblG-variant cells. This interaction decreased 2.2, 1.5 and 5.0-fold in the proximity ligation assay of cblC cells with p.R161Q and p.R206W mutations, and HEK cells with knock down expression of MS by siRNA, respectively, when compared with control cells. In 3D modelling and docking analysis, both truncated and full-size MS provide a loop anchored to MMACHC, which makes contacts with R-161 and R-206 residues. Our data suggest that the interaction of MS with MMACHC may play a role in the regulation of the cellular processing of Cbls that is required for Cbl cofactor synthesis.

OBJECTIVE: Sapropterin dihydrochloride, the synthetic form of 6R-tetrahydrobiopterin (BH4), is an approved drug for the treatment of patients with BH4-responsive phenylketonuria (PKU). The purpose of this study was to assess genotypes and data on the long-term effects of BH4/sapropterin on metabolic control and patient-related outcomes in 6 large European countries. METHODS: A questionnaire was developed to assess phenotype, genotype, blood phenylalanine (Phe) levels, Phe tolerance, quality of life, mood changes, and adherence to diet in PKU patients from 16 medical centers. RESULTS: One hundred forty-seven patients, of whom 41.9% had mild hyperphenylalaninemia, 50.7% mild PKU, and 7.4% classic PKU, were followed up over ≤12 years. A total of 85 different genotypes were reported. With the exception of two splice variants, all of the most common mutations were reported to be associated with substantial residual Phe hydroxylase activity. Median Phe tolerance increased 3.9 times with BH4/sapropterin therapy, compared with dietary treatment, and median Phe blood concentrations were within the therapeutic range in all patients. Compared with diet alone, improvement in quality of life was reported in 49.6% of patients, improvement in adherence to diet was reported in 47% of patients, and improvement in adherence to treatment was reported in 63.3% of patients. No severe adverse events were reported. CONCLUSIONS: Our data document a long-term beneficial effect of orally administered BH4/sapropterin in responsive PKU patients by improving the metabolic control, increasing daily tolerance for dietary Phe intake, and for some, by improving dietary adherence and quality of life. Patient genotypes help in predicting BH4 responsiveness.

Fluctuations in blood phenylalanine concentrations may be an important determinant of intellectual outcome in patients with early and continuously treated phenylketonuria (PKU). This review evaluates the studies on phenylalanine fluctuations, factors affecting fluctuations, and if stabilizing phenylalanine concentrations affects outcomes, particularly neurocognitive outcome. Electronic literature searches of Embase and PubMed were performed for English-language publications, and the bibliographies of identified publications were also searched. In patients with PKU, phenylalanine concentrations are highest in the morning. Factors that can affect phenylalanine fluctuations include age, diet, timing and dosing of protein substitute and energy intake, dietary adherence, phenylalanine hydroxylase genotype, changes in dietary phenylalanine intake and protein metabolism, illness, and growth rate. Even distribution of phenylalanine-free protein substitute intake throughout 24 h may reduce blood phenylalanine fluctuations. Patients responsive to and treated with 6R-tetrahydrobiopterin seem to have less fluctuation in their blood phenylalanine concentrations than controls. An increase in blood phenylalanine concentration may result in increased brain and cerebrospinal fluid phenylalanine concentrations within hours. Although some evidence suggests that stabilization of blood phenylalanine concentrations may have benefits in patients with PKU, more studies are needed to distinguish the effects of blood phenylalanine fluctuations from those of poor metabolic control. (C) 2013 The Authors. Published by Elsevier Inc. All rights reserved.

International audience; BACKGROUND: Sapropterin dihydrochloride, an EMEA-approved synthetic formulation of BH4, has been available in Europe since 2009 for PKU patients older than 4 years, but its use with younger children is allowed in France based on an expert recommendation. We report the cases of 15 patients treated under the age of 4 years and demonstrate the safety and efficacy of this treatment for patients in this age group. PATIENTS AND METHOD: We report the use of BH4 in 15 PKU patients treated before the age of 4 years. RESULTS: Fifteen patients were enrolled in this retrospective study. Mean phenylalaninemia at diagnosis was 542±164 μM and all patients had mild PKU (maximal phenylalaninemia: 600-1200 μM). BH4 responsiveness was assessed using a 24-hour BH4 loading test (20 mg/kg), performed during the neonatal period (n = 11) or before 18 months of age (n = 4). During the test, these patients exhibited an 80±12% decrease in phenylalaninemia. Long-term BH4 therapy was initiated during the neonatal period (n = 7) or at the age of 13±12 months (n = 8). The median duration of treatment was 23 months [min 7; max 80]. BH4 therapy drastically improved dietary phenylalanine tolerance (456±181 vs 1683±627 mg/day, p