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UNLABELLED: Sjogren-Larsson syndrome (SLS) is a neurocutaneous autosomal recessive disease caused by fatty aldehyde dehydrogenase (FADH) deficiency. This enzyme is involved in the biosynthesis pathways of some fatty acids, phytanic acid, and leukotrienes. The main features of the disease are its association with congenital ichthyosis, mental retardation, and spastic tetraplegia. METHODS: We report on the diagnostic and therapeutic management of 2 cases of SLS. RESULTS: The diagnosis of SLS was suspected in the first patient at 2 years of age before the clinical triad appeared and confirmed at 4 years of age by the culture of fibroblasts and the peak of lipids on 1.3 ppm spectroscopy. After 3 months of treatment with zileuton, an inhibitor of leukotriene synthesis, moderate clinical efficacy for pruritus and ichthyosis was observed. The second patient was diagnosed at 1 year of age with the association of psychomotor retardation and congenital ichthyosis, in accordance with acute Guillain-Barre syndrome. Diagnosis was confirmed with enzymology, and cerebral spectro-MRI featured an abnormal lipidic peak. Zileuton therapy was initiated at the time of diagnosis and was effective for pruritus after 6 months of treatment. CONCLUSION: We report 2 cases of SLS with delayed diagnosis, due to non neonatal symptoms. Treatment with zileuton shows partial efficacy especially in pruritus. The uncommon association of this rare dysmyelinating disease with Guillain-Barre syndrome in the second patient is discussed.

A 22 year-old woman with tyrosinemia type I (HT1) married her first cousin who is heterozygous for the same FAH mutation for which the patient is homozygous. During her pregnancy she was treated with diet (prescribed tyrosine intake 300 mg/day), and nitisinone (60 mg/day). Median plasma tyrosine levels were 560 μmol/L (range: 375-838, n = 21) and nitisinone 51 μmol/L (range: 41-57, n = 3) during pregnancy. She gave birth to a clinically healthy girl affected with tyrosinemia type 1. Birth was normal (birth weight 2615 g) and the baby had normal liver function, normal plasma alpha-fetoprotein concentrations, low urinary excretion of phenolic acids and no detectable succinylacetone. At birth, the baby had hypertyrosinemia (860 μmol/L in blood cord) and nitisinone levels of 14 μmol/L. Following molecular confirmation of the diagnosis of HT1 specific treatment began on day 15 by which time she had detectable urinary succinylacetone.

Resume La maladie de Niemann-Pick type C (NPC) est une maladie de surcharge lysosomale neuroviscerale, rare, autosomique recessive, liee a une anomalie du trafic intracellulaire de lipides conduisant a leur accumulation dans le cerveau, le foie, la rate et aussi le poumon. La presentation clinique de la maladie est heterogene et varie selon l’âge de debut. Chez l’enfant, on distingue les formes perinatales viscerales et les formes neurologiques infantiles precoces, infantiles tardives et juveniles. L’atteinte neurologique est progressive et souvent aspecifique mais quatre signes ont une grande valeur d’orientation diagnostique : une cholestase neonatale prolongee, une splenomegalie, des acces cataplectiques et surtout une paralysie supranucleaire verticale du regard. La confirmation du diagnostic necessite une culture de fibroblastes et l’etude moleculaire des genes NPC1 et NPC2. L’approbation recente d’un traitement specifique, qui reduit la progression de l’atteinte neurologique, rend essentiel un diagnostic precoce de NPC.

This paper describes MRI aspects of a leukodystrophy due to the Mitochondrial Neurogastrointestinal Encephalomyopathy syndrome in an adolescent girl investigated for nocturnal recurrent emesis leading to major cachexia.

In a series of 137 patients with methylmalonic acidaemia (MMA) and propionic acidaemia (PA) diagnosed since the early 1970s, we report in more detail 81 patients (51 MMA and 30 PA) diagnosed between 1988 and 2005. In this series, 14% of patients died at initial access revealing the disease before or despite treatment, 18% died later, and the remainder (68%) are still alive. All patients were treated with the same protocol of enteral feeds with a low-protein diet adjusted to individual tolerance, carnitine, antibiotics, and only occasional use of an amino acid (AA) mixture. There was intensive follow-up and monitoring using measurements of urinary urea. Thirty-nine patients with severe forms, followed for more than 3 years, are analysed in particular detail. Of the 17 PA patients, 6 had moderate disability (all neonatal-onset forms), whereas 11 were normal or slightly delayed in their mental development. Four presented with cardiomyopathy, of whom 2 died. Of the 22 MMA patients, 13 presented in the neonatal period, of whom 3 died later, 2 are in renal failure and only 5 are still alive and have a normal or slightly delayed mental development. In the 9 patients with late-onset forms, there were no deaths and all patients but one have normal mental development. Among the 39 patients, only 40% were given an AA supplement at 3 years, and 50% between 6 and 11 years. The actual intake of natural protein was 0.92, 0.78 and 0.77 g/kg per day at 3, 6 and 11 years, respectively, in patients without AA supplementation, whereas it was 0.75, 0.74 and 0.54 g/kg per day in the group who received small quantities of AA (0.4-0.6 g/kg per day). In both groups, feeding disorders were frequent: 55% at 3 years, 35% at 6 years and 12% at 11 years. Many patients were given a food supplement by tube overnight or were even exclusively tube fed: 60% at 3 years, 48% at 6 years and still 27% at 11 years. Growth velocity was near the normal values. Plasma valine and isoleucine were low to very low, as were leucine and phenylalanine but to a lesser extent. Albumin, vitamins, trace elements and markers of bone metabolism were within the normal values. IGF1, 24-hour urine calcium and body mass density were low. Body composition showed a normal to low lean mass and a normal to high fat mass.

Organic acidurias comprise many various disorders. Methylmalonic aciduria (MMA) and propionic aciduria (PA) are the most frequent diseases and the two organic acidurias for which we have better knowledge of the long-term outcome. Comparing the outcome of patients born before and after 1990, it appears that better neonatal and long-term management have improved the survival rate. Less than 20% of the patients died in either the neonatal period or before the age of 10 years. However, most surviving patients showed poor nutritional status with growth retardation and about 40% present some kind of visceral or neurological impairment. The developmental outcome may have improved in MMA patients, with IQ higher than 75 in about 40% patients aged more than 4 years. Conversely, poor intellectual development is the rule in PA patterns, with 60% having an IQ less than 75 and requiring special education. Successful liver and/or renal transplantations, in a few patients, have resulted in better quality of life but have not necessarily prevented neurological and various visceral complications. These results emphasize the need for permanent metabolic follow-up whatever the therapeutic strategy.

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.

Haematological symptoms can be helpful for the diagnosis of metabolic diseases. A megaloblastic anemia orientates to folate and cobalamine anomalies when associated with homocystinemia and decreased plasma methionine levels, or to congenital oroticuria (hypochromia), Pearson syndrome (sideroblasts and vacuolisation of precursors) and thiamine transporter abnormality (sideroblasts) in the absence of homocystinuria. An hemolytic anemia orientates to anomalies of anaerobic glycolysis, heme synthesis, or iron metabolism, and Wilson disease. A pancytopenia orientates to organic aciduria, lysinuric protein intolerance, mevalonic aciduria and lysosomal storage diseases (Gaucher, Niemann Pick, Wolman) when hepatosplenomegaly is present. Uremic hemolytic syndrome and hemophagocytic lymphohistiocytosis respectively orientate to B12 anomalies, lysinuric protein intolerance, lysosomal storage diseases and organic aciduria.

Branched chain organic acidurias are a group of disorders that result from an abnormality of specific enzymes involving the catabolism of branched chain amino acids (leucine, isoleucine, valine). Maple syrup urine disease (MSUD), isovaleric acidaemia (IVA), propionic aciduria (PA) and methylmalonic aciduria (MMA) represent the most commonly encountered abnormal organic acidurias. All these four disorders present in neonates as a neurologic distress of the intoxication type with either ketosis or ketoacidosis and hyperammonaemia. There is a free interval between birth and clinical symptoms. MMA, PA and IVA present with a severe dehydration, leuconeutropenia and thrombopenia which can mimic sepsis. All these disorders can be diagnosed by identifying acylcarnitine and other organic acid compounds in plasma and urine by gas chromatography mass spectrometry or tandem MS-MS. These disorders are amenable to treatment by removing toxic compounds and by using special diets and carnitine.

The cobalamin type C deficiency is a rare condition that results from impaired biosynthesis of both methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl). Hemizygous mutations of the HCFC1 gene explain the majority of clinically and biologically compatible cblC patients without MMACHC mutations (OMIM 309541). We report a family with two maternal half-brothers with multiple congenital anomalies and HCFC1 gene mutation in the second Kelch domain. Both presented with dysmorphic features (flat profile, cleft lip for one), increased nuchal translucency, prenatal onset microcephaly and hypospadias. Additionally to early onset intractable epilepsy and profound neurocognitive impairment, this familial observation suggests that HCFC1 gene should be considered in boys with midline malformations, even without proven cobalamin C deficiency.

Resume La tyrosinemie hereditaire de type I est une maladie de pronostic severe. Les causes principales de deces sont l'insuffisance hepatique, les crises neurologiques et l'hepatocarcinome. Le NTBC, en inhibant la 4-hydroxyphenylpyruvate dioxygenase, previent la formation des metabolites toxiques impliques dans les lesions hepatiques, renales et neurologiques. Observations Nous rapportons les resultats du NTBC chez trois nourrissons atteints de tyrosinemie de type I revelee par une insuffisance hepatique aigue severe. Le diagnostic a ete confirme par la mise en evidence d'une concentration plasmatique elevee de tyrosine et de methionine et d'une excretion urinaire anormale de succinyl acetone et d'acide δ-aminolevulinique. Le traitement par NTBC a ete debute 2 a 8 jours apres le debut des symptomes. La correction des fonctions de synthese hepatique a ete notee des la 3 e semaine de traitement. Apres 12 a 39 mois de recul, l'evolution reste favorable. Conclusion Ces resultats illustrent l'efficacite du NTBC dans les formes aigues de la maladie. Toutefois, les resultats a long terme restent a determiner, notamment en termes de prevention de l'hepatocarcinome et de toxicite propre au medicament.

A case of holocarboxylase synthetase (HCS) deficiency of late-infantile onset is presented and compared with the common manifestations in previously reported patients. Our patient had her first episode at 20 months followed by recurrent episodes of metabolic acidosis with ketolactic acidosis responding dramatically to a short trial of biotin and thiamin. The main clinical findings were metabolic acidosis with alteration in consciousness and respiration, which are in accordance with findings in earlier reported patients with both neonatal-onset and infantile-onset forms of HCS deficiency. The diagnosis of HCS deficiency was made only at the age of 5.5 years during a metabolic work-up when organic acid analysis was performed. This revealed elevated urinary excretion of the characteristics metabolites, 3-hydroxypropionate, 3-hydroxyisovalerate and methylcitrate, suggesting multiple carboxylase deficiency (MCD). MCD was demonstrated in fibroblasts of our patient, but only when the cells were grown in a medium with a very low biotin concentration of 10(-10) mol/L. Kinetics studies of reactivation of deficient propionyl-CoA carboxylase activity with biotin in intact fibroblasts revealed a midly decreased reactivation rate and only a 3-5 times higher biotin requirement as compared with controls. These findings are in accordance with a mild form of HCS deficiency. This child responded to 10 mg/day of biotin with normal lymphocyte carboxylase activities and adequate school performance at 10 years of age.

Primary persistent hyperinsulinaemic hypoglycaemia of infancy is rare. Diazoxide treatment remains the mainstay of medical therapy in long-term management. We reviewed 77 cases of primary persistent hyperinsulinism in neonates and infants who were treated with diazoxide and studied criteria predictive of therapeutic efficacy. The only criterion identified was age at manifestation. All but 1 of the 31 neonatal cases were unresponsive to diazoxide. Responsiveness increased with age: 12 of 39 early-infantile cases, and all seven late-infantile cases were diazoxide-responsive. In responders, a diazoxide dose of 10-15 mg/kg per day was always effective, suggesting an "all or none" response. Diazoxide-resistant hyperinsulinism is characterized by its severity with higher plasma insulin levels. The analysis of 46 surgically treated patients showed that the efficacy of diazoxide is not related to the aetiology of the pancreatic lesions. In six cases, after many years of management, diazoxide treatment was stopped without recurrence of hypoglycaemia. CONCLUSION: Diazoxide is an efficient treatment in the long-term management of most persistent hyperinsulinaemic hypoglycaemia of infancy revealed in infants and children but is usually ineffective in neonatal forms. Drug efficacy does not correlate with anatomical lesions. Medical treatment can sometimes be stopped after many years of management without recurrence of disease manifestations.

Resume Les myelogrammes des enfants presentant une intolerance aux proteines dibasiques avec lysinurie sont habituellement normaux, meme si des aspects d'autoerythrophagocytose ont ete decrits chez certains d'entre eux. Observation. — Un diagnostic d'intolerance aux proteines dibasiques avec lysinurie a ete porte chez deux freres âges de 12 et 15 ans a la suite d'une investigation immunohematologique. La symptomatologie avait debute en periode neonatale par une association de signes compatibles avec un diagnostic de syndrome d'activation macrophagique. Il existait une hepatosplenomegalie, une pancytopenie, une hypofibrinogenemie, une hypertriglyceridemie. Ulterieurement, l'hypothese d'une lymphohistiocytose familiale avait ete recusee devant l'evolution inhabituellement favorable et le caractere intermittent du syndrome d'activation macrophagique. Durant les annees qui ont suivi, outre les anomalies hematologiques, l'evolution s'etait caracterisee par l'installation d'une anorexie elective pour les proteines, avec retard de croissance, osteoporose et retard psychomoteur. Ce n'est qu'a 12 et 15 ans que l'investigation clinique et biologique de ces patients a permis de mettre en evidence une hyperammoniemie chronique. La supplementation en L-citrulline, en faisant apparaitre une hyperaminoacidurie specifique (arginine, ornithine, lysine), a permis le diagnostic. L'analyse des medullogrammes, pratiques en periode neonatale et lors du diagnostic, a revele une phagocytose particuliere des erythroblastes et des polynucleaires neutrophiles simultanement par des macrophages et des progeniteurs granuleux. Conclusions. — Cet aspect du myelogramme pourrait etre un des signes specifiques de la maladie. Ces donnees suggerent l'importance des investigations metaboliques devant tout syndrome d'activation macrophagique inexplique.

Resume L'hyperphenlalaninemie maternelle expose les femmes enceintes a un risque eleve d'avortement spontane et les enfants a naitre a un risque de microcephalie, d'arrieration mentale et de malformations congenitales, en particulier cardiaques. Quatre-vingt-quinze pour cent des meres dont la phenylalaninemie excede 20 mg/100 mL (1 200 μmol/L) ont au moins un enfaut mentalement retarde. La remise a un regime strict avant la conception et le controle de la phenylalaninemie tout au long de la grossesse reduisent ces risques. Les parametres de croissance de l'enfant, notamment son perimetre crânien, sont mieux conserves chez les femmes dont la phenylalaninemie a ete maintenue en dessous de 6 mg/100 mL (360 μmol/L) que chez celles dont la phenylalaninemie a ete plus souvent comprise entre 6 et 10 mg/100 mL (360–600 μmol/L). Il est par consequent hautement souhaitable que la grossesse soit programmee et qu'une contraception systematique soit mise en œuvre chez les jeunes femmes en âge de procreer, jusqu'a ce que la decision de mise en route d'une grossesse ait ete prise. Dans ce but, une information de ces jeunes filles et de leurs parents devrait etre realisee sans tarder et tous les efforts devraient etre entrepris afin de recenser les jeunes femmes hyperphenylalaninemiques depistees a la naissance et en âge de procreer, qu'elles aient ete traitees ou non par un regime de restriction. Enfin les medecins generalistes, les pediatres, les gynecologues-obstetriciens et les sages-femmes devraient etre sensibilises au risque de recurrence chez les femmes qui ont donne naissance a un enfant microcephale et/ou malforme, situation qui justifie pleinement un depistage « cible a. Une information dans la presse specialisee serait sans doute aussi d'une grande utilite.

We report 8 cases of severe cytochrome c oxidase deficiency with onset in the neonatal period. Clinical symptoms were heterogeneous: antenatal cerebral malformations, neurological distress with ketoacidosis, severe myopathy, or isolated respiratory control failure. Lactic acid was elevated in blood and/or CSF in 7 cases. Muscle biopsy (7 patients), liver biopsy (4 patients), and cultured skin fibroblasts (7 patients) were used to assess the cytochrome c oxidase deficiency. Among the patients, the enzymatic defect differed in the level of residual activity, expression in different tissues and subunit composition in muscle (as analysed by immunohistochemistry). Southern blot analysis of the mitochondrial DNA was normal in 7 patients. The heterogeneity of cytochrome c oxidase deficiency was therefore demonstrated by these clinical presentations and by the biochemical assessment of the enzyme defect. This reflects, most probably, the diverse nature of the causal mutations.

We report our cumulative experience for the prenatal diagnosis of succinic semialdehyde dehydrogenase (SSADH) deficiency in seven 'at-risk' pregnancies from four unrelated families. Prenatal diagnosis was performed by determination of 4-hydroxybutyric acid (4-HBA) concentration in amniotic fluid using isotope-dilution gas chromatography-mass spectrometry in conjunction with assay of SSADH activity in biopsied chorionic villus and/or cultured amniocytes. In three of four pregnancies predicted as affected, confirmation was obtained by demonstration of deficient SSADH activity in fetal tissues. Our results suggest that determination of 4-HBA concentration in amniotic fluid combined with enzyme determination in cultured or biopsied tissue represents a reliable method for the prenatal diagnosis of SSADH deficiency.

The clinical and morphologic findings of three patients with metabolic acidosis, methylmalonic aciduria, and homocystinuria are presented. The clinical evolution of the patients was similar and was characterized in the first weeks of life by failure to thrive, hypotonia, and lethargy associated with pancytopenia and hepatic dysfunction, eventually progressing to severe respiratory insufficiency and renal failure consistent with a hemolytic-uremic syndrome. The patients died at 40, 45, and 75 days of age. Biochemical analyses and complementation studies revealed a congenital anomaly of vitamin B12 metabolism (cobalamin C disease). Postmortem morphologic findings in all three cases were dominated by a thrombotic microangiopathy of the kidneys and lungs, diffuse hepatic steatosis, and megaloblastic changes in the bone marrow. A severe gastritis with striking cystic dysplastic mucosal changes and total absence of parietal and chief cells was a consistent finding in all three cases, the rest of the gastrointestinal tract appearing essentially normal. Cobalamin C disease is an intracellular defect of cobalamin metabolism with possible recessive inheritance that can result in multiorgan failure early in life, with a thrombotic microangiopathy and unusual changes in the gastric mucosa.

Diabetes mellitus is occasionally observed in patients with skeletal muscle respiratory chain deficiency, suggesting that skeletal muscle mitochondrial dysfunction might play a pathogenic role in type 2 diabetes (T2D). In support of this hypothesis, decreased muscle mitochondrial activity has been reported in T2D patients and in mouse models of diabetes. However, recent work by several groups suggests that decreased muscle mitochondrial function may be a consequence rather than a cause of diabetes, since decreased mitochondrial function in mice affords protection from diabetes and obesity. We review the data on this controversial but important issue of potential links between mitochondrial dysfunction and diabetes.

Hyperargininaemia is a rare inborn error of metabolism due to a defect in the final step of the urea cycle. Infantile onset is the most common presentation with recurrent vomiting and psychomotor delay associated with spastic paraparesis; chronic hyperammonaemia is often overlooked. Neonatal and early-onset presentations are very uncommon and their clinical course not well-described. We report on a 3-week-old hyperargininaemic girl who presented with neurological deterioration associated with liver failure and 47-day ammonia intoxication before diagnosis could be made and treatment started. Despite appropriate but delayed treatment, our patient exhibited severe psychomotor delay at age 1 year. Conclusion Early identification and management of this rare but potentially treatable affection is crucial as delayed management may result in poor neurological outcome.

Resume L'âge de decouverte et la symptomatologie revelatrice de l'intolerance aux proteines du lait de vache (IPLV) sont varies; l'acidose lactique y est exceptionnelle. Observation Un nourrisson de 32 jours avait ete affecte d'un malaise grave avec acidose metabolique et hyperlactacidemie. Cette enfant, sans antecedent neonatal et familial particulier, sevree a j25, avait eu a j29 un pic de fievre, puis une degradation neurologique progressive avec deux episodes de pâleur, puis perte de connaissance breve imposant l'hospitalisation. A l'admission, l'enfant etait lethargique et hypotonique. Le bilan infectieux etait negatif ainsi que les explorations neuroradiographiques. Il existait une acidose metabolique compensee avec une hyperlactacidemie (5,96 mmol/L). La recherche d'un reflux gastro-œsophagien, d'une hypertonie vagale et, compte tenu de l'atteinte neurologique avec acidose, d'une cytopathie mitochondriale etait negative. Apres 24 heures d'arret alimentaire, l'etat clinique s'est ameliore progressivement pour se normaliser a h48. L'enfant est sortie du service sous hydrolysat de proteines. La mere a tente une reintroduction « sauvagedes proteines de lait de vache (PLV) a j64, entrainant immediatement des manifestations allergiques de type reaginique. Malgre l'absence de tests biologiques specifiques, l'evolution clinique est en faveur d'une intolerance aux proteines du lait de vache. Conclusion Ce mode de revelation (tableau neurologique et hyperlactacidemie) est rare. L'origine de cette hyperlactacidemie reste meconnue, probablement liee a la souffrance tissulaire de la muqueuse intestinale, organe glycolytique exclusif.

International audience; BACKGROUND: Cobalamin C disease is the most common inborn error of cobalamin metabolism with an autosomal recessive mode of inheritance and mutations within the MMACHC gene. Clinical features, including systemic, haematological and neurological abnormalities, usually occur in the first year of life. Adolescent and adult onset presentations are rare. METHODS: We report on the clinical, molecular and imaging features in three patients aged 40, 42 and 42 years at the last follow-up. We examine these cases together with eight previously described cases to determine the clinical and molecular features of the disease in adults. RESULTS: Mean age at onset of clinical symptoms was 26 years; clinical features included predominant neurological disturbances and thromboembolic complications. White matter abnormalities on brain MRI were sometimes observed. Most patients (eight of nine patients investigated) were compound heterozygotes for the 271dupA mutation and a missense mutation. Intramuscular or intravenous hydroxycobalamin therapy stopped the progression of the disease and resulted in a better clinical outcome and favourable biological status in 7/9 treated cases, while the two untreated patients died quickly. CONCLUSIONS: As cobalamin C disease and related disorders of homocysteine metabolism are treatable conditions, homocysteinaemia should be included in the investigations of patients with progressive neurological deterioration, unexplained psychiatric disturbances or recurrent thromboembolic events.

We report on a 1-year-old boy, with carbohydrate-deficient glycoprotein (CDG) syndrome type I due to phosphomannomutase deficiency. Radiologic examination of the skeleton revealed previously unreported bone abnormalities that could be included in a dysostosis multiplex: wide ribs, squared iliac wings, horizontal acetabular roofs, widening and modeling abnormalities of ischial and pubic bones, dorsolumbar kyphosis, and slight hook-like dysplasia of the first lumbar vertebrae. Wormian bones were also present. We suggest that these features may be due to hypoglycosylation of bone proteins and that CDG syndrome type I should be included in the differential diagnosis of dysostosis multiplex.

Thiamin deficiency can lead to various clinical presentations, such as classical beriberi, Wernicke's encephalopathy, acute thiamin deficiency syndrome (ATD) and cardiovascular shock (Nakasaki et al 1997; Remond et al 1999; Romanski and MacMahon 1999; Svahn et al 2003). Characteristics of total parenteral nutrition (TPN)-induced ATD include a history of TPN with 10-30 days without vitamin supplementation, severe lactic acidosis refractory to massive doses of bicarbonate, α-ketoacid accumulation in plasma and urine, resolution of clinical and metabolic features within a few hours following the injection of thiamin, and rapid progression of the disease and fatal outcome without thiamin supplementation. The diagnosis can be confirmed by demonstrating a low thiamin concentration in a total blood sample (Kitamura et al 1996). To date, only two cases of ATD during TPN in the neonatal period have been reported (Matern et al 1996). Here, we report on a series of 11 neonates with strongly suspected or confirmed severe lactic acidosis related to ATD during TPN, collected from 1973 to 2001 following a French collaborative study (Table 1). The ages of the patients ranged from birth to 3.5 months of life. In all cases, the underlying disease for which TPN was investigated was bowel intolerance or malformation. There were no features of primary haemodymamic or septic distress. Clinical features appeared from 11 to 29 days (average = 17.8 days) after the beginning of TPN without thiamin supplementation (or after the end of thiamin supplementation), and included tachypnoea, hypotension, tachycardia, haemodynamic distress, vomiting, agitation, hypotonia and lethargy. Only one patient did not present anv clinical features during the 7-day period of thiamin deficiency-related lactic acidosis.

The authors report 7 years of follow-up evaluation of a patient with coenzyme Q 10 (CoQ 10 ) deficiency. Initial symptoms of exercise intolerance and hyperlactatemia improved markedly with substitutive treatment. However, CoQ 10 supplementation did not prevent the onset of a cerebellar syndrome. A switch to idebenone treatment resulted in clinical and metabolic worsening, which disappeared with subsequent CoQ 10 treatment. CoQ 10 defects may cause progressive neurologic disease despite supplementation.

OBJECTIVE To assess the prevalence of in vivo detectable abnormalities of lactate metabolism in mitochondrial disorders. DESIGN Retrospective study in a metabolic investigation unit. PATIENTS 28 patients with a respiratory chain disorder identified from biochemical or genetic analyses, or both, and 133 age matched controls. Controls were children in whom causes of secondary hyperlactataemia and/or disorders, affecting the energy pathways could be excluded. METHODS Lactate and pyruvate were measured in blood, together with other intermediary metabolism indices, before and one hour after four meals each day. Lactate and creatinine in a 24 hour urine sample collected at the same time were analysed. When basal hyperlactataemia was not evident, an intravenous glucose or pyruvate loading test was performed as a provocative test. RESULTS Abnormal lactate metabolism was found in 25 of 28 patients thus demonstrating the potential usefulness of these investigations in the diagnosis of mitochondrial diseases. Moderate lactate accumulation was present in relatively mild disease, associated with a mitochondrial DNA mutation and combined respiratory complexes deficiency. By contrast, high lactate concentrations were observed in very young children, with severe disease, isolated complex deficiency, and no apparent mitochondrial DNA defect.

A retrospective study was performed on the clinical outcome and long-term treatment of 17 patients with propionic acidaemia diagnosed during the last 20 years in our hospital. The study group consisted of 12 patients with early onset type of disease and 5 patients with late onset. Seven (41%) patients died, five with early onset and two with late onset. The deceased early onset patients had a median survival of 0.4 years while the deceased late onset patients died at the age of 2.8 and 4 years respectively. Median age of the living early onset patients was 5.2 (1-9.25) years, the late onset patients were 4, 7 and 23 years old. Patients were all treated with natural protein restriction and in most cases carnitine and metronidazole were added. The early onset patients were almost all treated with daily home tube feeding. The mean natural protein intake of early onset patients (6.3 +/- 1.5 g/day) was significantly lower than the natural protein intake of late onset patients (17.6 +/- 5.3 g/day). Supplemental protein intake was higher in early onset patients. The general neurological outcome of our study group was satisfactory with a better outcome for early onset patients. As to growth, many patients showed a failure to thrive, this was particularly for height. The strong protein restriction during the first years of life probably contributed to this.The prognosis for patients with propionic acidaemia appeared to be satisfactory in terms of survival and outcome characteristics such as neurological and mental development. Despite these results the authors feel that the prognosis and quality of life of these patients might be improved with liver transplantation or possibly somatic gene therapy in the future.

This paper underscores the contribution of routine morphological examination of skeletal muscle in patients with lactic acidosis. Mitochondrial disorders are by far the most common causes of primary lactic acidosis, in which muscle biopsy analysis helps in diagnosis and in the search for the molecular anomalies. Thus, we focus our attention on one particular point: the contribution of the morphological study of muscle biopsy in primary lactic acidosis due to mitochondrial disorders, especially mitochondrial respiratory-chain diseases.

Carnitine-acylcarnitine translocase deficiency is a newly recognized inborn error of metabolism that involves transport of long-chain fatty acids into mitochondria, which in turn impairs mitochondrial beta-oxidation, and ketogenesis. We report a new familial example; the affected twins had neonatal distress, hyperammonemia, and transient intracardiac conduction defects. Clinical and biochemical analysis of both our patients and the two previously reported patients revealed that this inherited defect could be manifested during the neonatal period without any of the signs classically associated with fatty oxidation defects. In contrast, all four patients had sustained and "isolated" hyperammonemia, which could be misinterpreted as being caused by urea cycle defects. We conclude that carnitine-acylcarnitine translocase deficiency is a potential differential diagnosis in neonates with unexplained neonatal hyperammonemia. Cardiac and muscle involvement may represent further early pivotal symptoms.

Two brothers, aged 27 and 20 months, born from consanguineous healthy parents, presented with cardiomyopathy, lactic acidosis and carnitine abnormalities in serum and muscle, without clinical evidence of muscle involvement. The histochemical reaction for cytochrome c oxidase (COX) activity was negative in all muscle fibres, although the holoenzyme and subunits were present at a normal level, as shown by immunocytochemistry. The COX activity was, respectively, 5 and 25% of control values, in muscle biopsies. Partial deficiency of complex IV was confirmed in fresh isolated muscle mitochondria from patient 2 and was associated with a defect of complex I. Patient 1 died at age 3 yr 6 months. Partial improvement of cardiomyopathy in patient 2 was obtained under carnitine therapy, but seizures occurred and CT scan and magnetic resonance imaging (MRI) revealed thalamic hypodensity. Thus, the disorder appears to be progressive despite the clinical stabilization of the cardiomyopathy. This further demonstrates the complexity and clinical heterogeneity of combined respiratory chain complex deficiencies.

We describe two asymptomatic newborns with nutritional vitamin B12 deficiency in whom increased urinary methylmalonic acid was detected by routine neonatal screening at 3 weeks of age. Both infants were exclusively breast-fed. One mother suffered from pernicious anaemia, and the other was a strict vegetarian. Both mothers had no clinical or haematological abnormality, aside from a borderline mean corpuscular volume for the vegetarian mother. This report illustrates the early appearance of functional vitamin B12 deficiency in breast-fed infants of vitamin B12-depleted mothers. It also demonstrates that urinary methylmalonic acid measurement is a sensitive indicator of tissue vitamin B12 deficiency.

We describe a patient with severe muscle cytochrome c oxidase deficiency who had de Toni-Fanconi-Debre syndrome and acute neurologic deterioration resembling Leigh syndrome, without clear evidence of muscle abnormality. Metabolic investigations revealed elevated cerebrospinal fluid lactate values contrasting with normal blood lactate, and high 3-hydroxybutyrate/acetoacetate ratio with normal lactate/pyruvate ratio. This case emphasizes the importance of performing metabolic and biochemical investigations in every patient with Leight syndrome, even in the absence of hyperlactatemia or myopathy.

Peroxisomes were visualized by cytochemical staining for catalase or/and electron microscopy in liver biopsies of two boys with childhood adrenoleukodystrophy (ALD), and of two girls with autopsy confirmed neonatal adrenoleukodystrophy (NALD). In a third patient previously described as NALD, unusual organelles were seen which may be large abnormal microbodies. Enlarged peroxisomes (determined by morphometry) were also present in the livers of the other two NALD patients. In the ALD patient whose clinical disease was more severe, peroxisomes were larger than in the older ALD case. Catalase staining was diminished and markedly heterogeneous. Additional unusual features such as a separate population of tubular forms, contact with fat droplets, of tubular forms, contact with fat droplets, marginal plate and invaginations containing glycogen were seen in the neonatal cases. These data are compared to the enlarged or elongated peroxisomes and heterogeneous staining in the thiolase-deficient "pseudo-Zellweger" patient (Goldfischer et al. 1986) and in 2 siblings with acylCoA oxidase deficiency (Poll-Thé et al. 1986, 1988). Enlarged peroxisomes are a common feature in this group of patients with peroxisomal deficiency disorders, suggesting that increased size and lowered metabolic capacity are associated. Nevertheless a marked morphopathological heterogeneity of peroxisomes thus exists in syndromes described as NALD including previously published cases. Most likely this heterogeneity reflects different enzymatic deficiencies, as confirmed by the biochemical data available. Clinically similar syndromes cover divergent microscopical and enzymatic peroxisomal patterns, and naming of the disease should be adapted to reflect such data. Cytochemical studies are urged in every suspected patient.

Summary Of 61 newborns with disorders in amino acid metabolism, 20 had seizures; 15 of them have been recorded. Clinically, seizures are mostly partial clonic jerks. There seems to be some homogeneity of EEG features in relation to causal amino acidopathy. In every case where seizures, either electroclinical or only infraclinical, occurred the evolution was very poor, even in those diseases that would have had a good prognosis. Therefore the EEG in the newborns is especially interesting, both as an aid to diagnosis by interictal recording and as a prognostic tool by registration of seizures.

Infantile Refsum's disease was diagnosed in three male patients, presenting with facial dysmorphia, retinitis pigmentosa, neurosensory hearing loss, hepatomegaly, osteopenia and delayed growth and psychomotor development. An elevated plasma phytanic acid concentration and a deficient phytanic acid oxidase activity in fibroblasts were found with an accumulation of very long chain fatty acids in plasma and fibroblasts. There were elevated pipecolic acid levels in plasma, urine and CSF, and abnormal bile acid metabolites in plasma. Deficient activity of acylCoA: dihydroxyacetone phosphate acyl transferase was found in thrombocytes and fibroblasts of these patients as well as an impaired de novo plasmalogen biosynthesis in fibroblasts. These biochemical abnormalities, previously described in the Zellweger syndrome, suggest multiple peroxisomal dysfunction in our patients.

Every newborn with unexplained neurological deterioration, ketosis, metabolic acidosis or hypoglycaemia should be suspected of having an inherited error of intermediary metabolism. Many of these conditions can be diagnosed clinically with the aid of simple laboratory investigations. Since a substantial number of these diseases respond well to treatment but may otherwise be fatal, and in order to assure adequate prenatal diagnosis in subsequent pregnancies, a high index of suspicion and rapid diagnosis are necessary in the face of the clinical presentations described. According to three major clinical presentations observed in 218 neonates with inborn errors of intermediary metabolism (neurological distress 'intoxication' type, neurological distress 'energy-deficiency' type and hypoglycaemia with liver dysfunction) and according to the proper use of few laboratory investigations, we propose a method of diagnosis which groups these children into five categories. Initial therapy, and sophisticated investigations can be planned on the basis of this grouping.

Hyperammonia has been reported in several disorders of branched chain amino acids metabolism including propionic, isovaleric, methylmalonic acidemia and B ketothiolase deficiency 1. Nevertheless the true incidence of hyperammonemia and its variation during the course of these diseases are not yet well known. The purpose of this study was to compare the blood ammonia concentrations and the concomitant serum organic acid accumulation in patients with propionic, isovaleric and methylmalonic acidemia.