Pyruvate carboxylase deficiency type C; variable presentation and beneficial effect of triheptanoin.

Pyruvate carboxylase is a mitochondrial enzyme essential for the tricarboxylic acid cycle (TCA), gluconeogenesis and fatty-acid synthesis. Pyruvate carboxylase deficiency (PCD) mostly presents with life-limiting encephalopathy (types A/B). A milder type C presentation is rare, with a comparatively favourable prognosis. Therapies remain essentially supportive. Triheptanoin is an odd-chain triglyceride, with the potential to replenish TCA intermediates (anaplerosis), and its metabolites cross the blood-brain-barrier. Outcomes of triheptanoin treatment in PCD types A/B have been disappointing, but have not been reported in type C. Here, we present two new patients with PCD type C, and report the response to treatment with triheptanoin in one. Patient 1 (P1) presented with neonatal-onset lactic acidosis and recurrent symptomatic lactic acidosis following exercise and during illnesses, with frequent hospitalisations. Speech development was delayed. MRI-brain showed delayed cerebral myelination. Patient 2 (P2) presented with episodic ketoacidosis, hyperlactataemia and hypoglycaemia at 2 years of age, with gross motor delay and mild global volume loss on MRI brain. Treatment with triheptanoin was commenced in P1 at 3 years of age with up-titration to 35 mL/day (25% of daily energy intake) over 6 months, due to transient diarrhoea. Dietary long-chain triglycerides were restricted, with fat-soluble vitamin supplementation. Subsequently, hospitalisations during intercurrent illnesses decreased, post-exertional hyperlactataemia resolved and exercise tolerance improved. Continued developmental progress was observed, and repeat MRI 18 months after initiation showed improved myelination. Triheptanoin was well-tolerated and appeared efficacious during 2 years' follow-up, and has potential to restore energy homeostasis and myelin synthesis in PCD type C.

Successful reversal of propionic acidaemia associated cardiomyopathy: evidence for low myocardial coenzyme Q10 status and secondary mitochondrial dysfunction as an underlying pathophysiological mechanism.

Dilated cardiomyopathy is a rare complication in propionic acidaemia (PA). Underlying pathophysiological mechanisms are poorly understood. We present a child of Pakistani consanguineous parents, diagnosed with late-onset PA at 18months of age. He presented a mild phenotype, showed no severe further decompensations, normal growth and psychomotor development on a low protein diet and carnitine supplementation. At 15years, a mildly dilated left ventricle was noticed. At 17years he presented after a 2-3month history of lethargy and weight loss with severe decompensated dilated cardiomyopathy. He was stabilised on inotropic support and continuous haemofiltration; a Berlin Heart biventricular assist device was implanted. He received d,l-hydroxybutyrate 200mg/kg/day, riboflavin and thiamine 200mg/day each and coenzyme Q10 (CoQ10). Myocardial biopsy showed endocardial fibrosis, enlarged mitochondria, with atypical cristae and slightly low respiratory chain (RC) complex IV activity relative to citrate synthase (0.012, reference range 0.014-0.034). Myocardial CoQ10 was markedly decreased (224pmol/mg, reference range 942-2738), with a marginally decreased white blood cell level (34pmol/mg reference range 37-133). The dose of CoQ10 was increased from 1.5 to 25mg/kg/day. Cardiomyopathy slowly improved allowing removal of the external mechanical cardiac support after 67days. We demonstrate for the first time low myocardial CoQ10 in cardiomyopathy in PA, highlighting secondary mitochondrial impairment as a relevant causative mechanism. According to these findings, a high-dose CoQ10 supplementation could be a potential adjuvant therapeutic to be considered in PA-related cardiomyopathy.

Successful Desensitisation in a Patient with CRIM-Positive Infantile-Onset Pompe Disease.

Pompe disease (PD) is a severe life-threatening disease in which enzyme replacement therapy (ERT) with alglucosidase alfa is the only treatment available. Recently it has been shown that antibody formation may have a significant adverse effect on response to ERT. We report a cross-reactive immunologic material (CRIM)-positive PD infant who developed severe infusion-associated reactions (IARs) after 15 uneventful months of ERT. We successfully got the child to tolerate the ERT by a desensitisation protocol. We diluted the total amount of standard alglucosidase alfa infusion (20 mg/kg/dose) to 1/100 (0.2 mg/kg/dose). The original infusion rates were maintained. We doubled this dose every week. No premedication was given. In 8 weeks, we reached the standard dose without any IAR. No further reactions have been observed during 6 months of follow-up. Importantly, clinical deterioration that was observed during the period of reduced enzyme delivery has almost completely reversed. We conclude that this protocol was effective in our patient, while being safe and easy to follow, and may be suitable in selected cases.

Dietary management of urea cycle disorders: European practice.

BACKGROUND: There is no published data comparing dietary management of urea cycle disorders (UCD) in different countries. METHODS: Cross-sectional data from 41 European Inherited Metabolic Disorder (IMD) centres (17 UK, 6 France, 5 Germany, 4 Belgium, 4 Portugal, 2 Netherlands, 1 Denmark, 1 Italy, 1 Sweden) was collected by questionnaire describing management of patients with UCD on prescribed protein restricted diets. RESULTS: Data for 464 patients: N-acetylglutamate synthase (NAGS) deficiency, n=10; carbamoyl phosphate synthetase (CPS1) deficiency, n=29; ornithine transcarbamoylase (OTC) deficiency, n=214; citrullinaemia, n=108; argininosuccinic aciduria (ASA), n=80; arginase deficiency, n=23 was reported. The majority of patients (70%; n=327) were aged 0-16y and 30% (n=137) >16y. Prescribed median protein intake/kg body weight decreased with age with little variation between disorders. The UK tended to give more total protein than other European countries particularly in infancy. Supplements of essential amino acids (EAA) were prescribed for 38% [n=174] of the patients overall, but were given more commonly in arginase deficiency (74%), CPS (48%) and citrullinaemia (46%). Patients in Germany (64%), Portugal (67%) and Sweden (100%) were the most frequent users of EAA. Only 18% [n=84] of patients were prescribed tube feeds, most commonly for CPS (41%); and 21% [n=97] were prescribed oral energy supplements. CONCLUSIONS: Dietary treatment for UCD varies significantly between different conditions, and between and within European IMD centres. Further studies examining the outcome of treatment compared with the type of dietary therapy and nutritional support received are required.

[Mourning a chronic disease: diagnostic error experienced by two families]. / Faire le deuil d'une maladie chronique : vécu de l'erreur diagnostique par deux familles.

We report on two pediatric cases with a diagnosis of hereditary metabolic disease established for several years and secondarily disproved. Retrospective interviews conducted 1 year after the announcement of the absence of the illness, the psychological reactions were analyzed. Through this clinical experience, the authors suggest that the traumatism caused by the announcement of the diagnosis may be similar to that which occurred when invalidation of the disease is pronounced. Four steps predominate: relief, anger, guilt, and problems mourning the disease experienced in solitude.

[New insights into perinatal hemochromatosis]. / Nouveaux concepts dans l'hémochromatose périnatale.

Perinatal hemochromatosis (PH) includes neonatal acute liver failure (ALF) with cirrhosis and extrahepatic iron overload sparing the reticuloendothelial system. This is the main cause of neonatal ALF. Prognosis is very poor, usually with neonatal death or neonatal orthotopic liver transplantation occurring in more than 70%. The recurrence rate is more than 90%. Diagnosis is hard to make and is proved after exclusion of other neonatal ALF causes. A recent physiopathological hypothesis proposed HP as a maternofetal alloimmune disease against the fetal liver. A maternal antibody may activate the terminal complement cascade, responsible for the membrane attack complex directed against fetal hepatocytes. Maternal prenatal treatment after a pregnancy complicated by PH modifies the course and the prognosis of this disease. In France, approval of prenatal IVIG treatment is required after analysis of clinical and pathological data by a national multidisciplinary committee.

[Medium-chain acyl-CoA-dehydrogenase (MCAD) deficiency: French consensus for neonatal screening, diagnosis, and management]. / Déficit en acyl-CoA-déshydrogénase des acides gras à chaîne moyenne (MCAD): consensus français pour le dépistage, le diagnostic, et la prise en charge.

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.

[Sjögren-Larsson syndrome: 2 case reports]. / Le syndrôme de Sjögren-Larsson: à propos de 2 cas.

UNLABELLED: Sjögren-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-Barré 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-Barré syndrome in the second patient is discussed.

[Chorioangiomatosis: a rare etiology of nonimmune hydrops fetalis. Obstetric and pediatric implications for patient care]. / La chorioangiomatose : une cause rare d'anasarque foetoplacentaire non immune. Implications pratiques obstétrico-pédiatriques.

UNLABELLED: We report a case of chorioangiomatosis with hydrops fetalis as a complication. OBSERVATION: Hydrops fetalis associated with fetal distress led to preterm birth at 33 GW. Resuscitation was needed at birth. A systematic histologic exam showed diffuse chorioangiomatosis. There was no congenital hemangioma. COMMENTS: We describe the features of chorioangiomatosis, a rare cause of nonimmune hydrops fetalis. Prenatal diagnosis of chorioangiomatosis before early recognition of severe maternal and fetal complications during pregnancy is infrequent, thus precluding early management of the pregnancy. Reports of associated chorioangioma and infantile hemangioma are frequent, illustrated with a recent pathophysiological hypothesis involving embolism of a placental angioblast as for the cause of congenital hemangioma. Investigations for associated cutaneous or visceral infantile hemangioma should be undertaken when chorioangioma is diagnosed.

[Long QT syndrome: an underestimated cause of sudden infant death]. / Le syndrome du QT long congénital : une cause sous-estimée de la mort subite inexpliquée du nourrisson.

Congenital long QT syndrome (LQTS) is an inherited arrhythmia that can be sporadic or familial. It predisposes to sudden cardiac death by ventricular fibrillation, which can occur at any age, particularly in neonates. Recent postmortem molecular screening surveys have shown that 10 to 12% of sudden infant death syndrome (SIDS) cases were potentially related to congenital long QT syndrome. Current SIDS etiological surveys fail to diagnose LQTS. Specific questioning and electrocardiographic screening of first-degree relatives could greatly facilitate LQTS diagnosis. We propose adding these to screening modalities after a SIDS incident. Neonatal electrocardiographic screening could allow early identification of LQTS and adapted treatment and follow-up.

[End-of-life and euthanasia, an intensive care team's experience]. / Fin de vie et euthanasie, enquête sur le vécu d'une équipe soignante de réanimation.

OBJECTIVES: The improvement in the medical techniques used in intensive care units over the last 30 years has led to a different approach towards the end of life and death. Our study has underlined the feelings of all the staff of an intensive care unit towards the various difficulties engendered by death and the question of euthanasia. RESULTS: Conducted in the particular context of an intensive care unit, this work is a survey on the staff's feelings and factual experiences, in order to promote discussions on this painful subject. Sixty-one percent of the persons surveyed declared that euthanasia was ethically acceptable. The patients take the initiative of the request (92%) and the cohesion of the team is unanimously required. Pain and corporeal deterioration are the first motivations. DISCUSSION: Euthanasia is a difficult question, sometimes impassionate, and the care units have to consider whether they are concerned by the quality of their patients' care. The press regularly issues reports on this. But beyond these quantified questions, the staff who care for these ill patients are often very discreet. The regular confrontation with this situation changes the medical team's view of the profession.