Pregnancy management and outcome in patients with four different tetrahydrobiopterin disorders.

INTRODUCTION: Inborn errors of tetrahydrobiopterin (BH4) biosynthesis or recycling are a group of very rare neurometabolic diseases. Following growing awareness and improved availability of drug treatment the number of patients with BH4 disorders reaching adulthood is constantly increasing. Pregnancy care of patients with these disorders is therefore a new challenge for clinicians. METHODS: This retrospective study summarises for the first time clinical and biochemical monitoring data of 16 pregnancies in seven women with different disorders of BH4 metabolism and evaluates treatment regimens before and during pregnancy in relation to the obstetrical outcome and paediatric follow-up. RESULTS: Worsening of pre-existing neurological symptoms or occurrence of new symptoms during pregnancy was not observed in most of the cases. Treatment regimens remained mostly unchanged. Pregnancies were not complicated by disease-specific features. Organ abnormalities, miscarriage, prematurity, IUGR and chromosomal changes were occasionally reported, without showing any association with the standard drug treatment for BH4 deficiencies. CONCLUSION: Although our data on 16 pregnancies in seven patients did not present any association of standard drug treatment with an increased rate of pregnancy complications, abnormal obstetrical or paediatric outcome, an intensive clinical and biochemical supervision by a multidisciplinary team before, during and after the pregnancy in any BH4 deficiency is essential since available data on pregnancies in patients with BH4 deficiencies is limited.

Mammary candidiasis: molecular-based detection of Candida species in human milk samples.

In this prospective and monocentric study, we investigated the performance of a commercialized real-time polymerase chain reaction (RT-PCR) test system for the specific detection of DNA from Candida albicans, C. dubliniensis, C. glabrata, C. krusei, C. lusitaniae, C. parapsilosis, and C. tropicalis in human milk samples of patients suspicious of mammary candidiasis. For this purpose, 43 breast-feeding women with characteristic symptoms of mammary candidiasis and 40 asymptomatic controls were enrolled. By culture, Candida spp. were detected in 8.8 % (4/46) and 9.3 % (4/43) of patient and control samples, respectively. Candida albicans (2/46), C. parapsilosis (1/46), and C. guilliermondii (1/46) were present in patient samples, and C. lusitaniae (3/43) and C. guilliermondii (1/43) were present in the controls. After RT-PCR was applied, Candida spp. were found to be present in 67.4 % (31/46) and 79.1 % (34/43) of patient and control samples investigated, respectively. PCR detection of C. albicans and C. parapsilosis revealed only a low sensitivity and specificity of 67.4 % and 41.9 %, respectively. Our data do not support the use of Candida RT-PCR for sensitive and specific diagnosis of mammary candidiasis.

Ketogenic diets in patients with inherited metabolic disorders.

Ketogenic diets (KDs) are diets that bring on a metabolic condition comparable to fasting, usually without catabolism. Since the mid-1990s such diets have been widely used in patients with seizures/epilepsies, mostly children. This review focuses on the use of KDs in patients with various inherited metabolic disorders (IMD). In glucose transporter type 1 deficiency syndrome (GLUT1-DS) and pyruvate dehydrogenase complex (PDHc) deficiency, KDs are deemed the therapy of choice and directly target the underlying metabolic disorder. Moreover, in other IMD, mainly of intermediary metabolism such as glycogen storage diseases and disorders of mitochondrial energy supply, KDs may ameliorate clinical symptoms and laboratory parameters. KDs have also been used successfully to treat symptoms such as seizures/epilepsy in IMD, e.g. in urea cycle disorders and non-ketotic hyperglycinemia. As a note of caution, catabolism may cause the condition of patients with IMD to deteriorate and should thus be avoided during KDs. For this reason, careful monitoring (clinical, laboratory and apparatus-supported) is warranted. In some IMDs specific macronutrient supply is critical. Therefore, in cases of PDHc deficiency the carbohydrate intake tolerated without lactate increase and in urea cycle disorders the protein tolerance should be determined. Considering this, it is particularly important in patients with IMD that the use of KDs be individualized and well documented.

Chromosomal microaberrations in patients with epilepsy, intellectual disability, and congenital anomalies.

Epilepsy is a common finding in patients with chromosomal macro- and micro-rearrangements but only few aberrations show a constant pattern of seizures. DNA array-based studies have reported causative copy number variations (CNVs) in 5-30% of patients with epilepsy with or without co-morbidities. The interpretation of many of the detected CNVs remains challenging. In order to identify CNVs carrying epilepsy-related genes we investigated 43 children with various patterns of epileptic seizures, intellectual disability (ID), and minor dysmorphism, using the Illumina® Infinium Human1M-DuoV1 array. In three patients we found likely causative de novo CNVs, i.e. deletions in 1q41q42.12 (3.4 Mb) and 19p13.2 (834 kb), and a mosaic two-segment duplication in 17p13.2 (218 kb) and 17p13.1 (422 kb). In six additional patients there were aberrations (a deletion in one and duplications in five patients) with uncertain clinical consequences. In total, the finding of causative chromosomal micro-rearrangements in 3 out of 43 patients (7%) and potentially causative CNVs in 6 additional patients (14%) with epilepsy and ID but without major malformations confirms the power of DNA arrays for the detection of new disease-related genetic regions.

Propionic acidemia: neonatal versus selective metabolic screening.

BACKGROUND: Whereas propionic acidemia (PA) is a target disease of newborn screening (NBS) in many countries, it is not in others. Data on the benefit of NBS for PA are sparse. STUDY DESIGN: Twenty PA patients diagnosed through NBS were compared to 35 patients diagnosed by selective metabolic screening (SMS) prompted by clinical findings, family history, or routine laboratory test results. Clinical and biochemical data of patients from 16 metabolic centers in Germany, Austria, and Switzerland were evaluated retrospectively. Additionally, assessment of the intelligent quotient (IQ) was performed. In a second step, the number of PA patients who have died within the past 20 years was estimated based on information provided by the participating metabolic centers. RESULTS: Patients diagnosed through NBS had neither a milder clinical course regarding the number of metabolic crises nor a better neurological outcome. Among NBS patients, 63% were already symptomatic at the time of diagnosis, and <10% of all patients remained asymptomatic. Among all PA patients, 76% were found to be at least mildly mentally retarded, with an IQ <69. IQ was negatively correlated with the number of metabolic decompensations, but not simply with the patients' age. Physical development was also impaired in the majority of patients. Mortality rates tended to be lower in NBS patients compared with patients diagnosed by SMS. CONCLUSION: Early diagnosis of PA through NBS seems to be associated with a lower mortality rate. However, no significant benefit could be shown for surviving patients with regard to their clinical course, including the number of metabolic crises, physical and neurocognitive development, and long-term complications.

Mutation analysis in 54 propionic acidemia patients.

Deficiency of propionyl CoA carboxylase (PCC), a dodecamer of alpha and beta subunits, causes inherited propionic acidemia. We have studied, at the molecular level, PCC in 54 patients from 48 families comprised of 96 independent alleles. These patients of various ethnic backgrounds came from research centers and hospitals in Germany, Austria and Switzerland. The thorough clinical characterization of these patients was described in the accompanying paper (Grünert et al. 2012). In all 54 patients, many of whom originated from consanguineous families, the entire PCCB gene was examined by genomic DNA sequencing and in 39 individuals the PCCA gene was also studied. In three patients we found mutations in both PCC genes. In addition, in many patients RT-PCR analysis of lymphoblast RNA, lymphoblast enzyme assays, and expression of new mutations in E.coli were carried out. Eight new and eight previously detected mutations were identified in the PCCA gene while 15 new and 13 previously detected mutations were found in the PCCB gene. One missense mutation, p.V288I in the PCCB gene, when expressed in E.coli, yielded 134% of control activity and was consequently classified as a polymorphism in the coding region. Numerous new intronic polymorphisms in both PCC genes were identified. This study adds a considerable amount of new molecular data to the studies of this disease.

Successful implementation of classical ketogenic dietary therapy in a patient with Niemann-Pick disease type C.

BACKGROUND: Niemann-Pick disease type C (NP-C) is a neurodegenerative disease for which only palliative treatment exists, and only miglustat is effective in stabilizing neurological manifestations of NP-C. Ketogenic dietary therapies (KDT) are successfully used in patients with seizure disorders, including those associated with various inherited metabolic diseases (IMD), to reduce seizure frequency and medication requirement as well as to confer neuroprotection. Since patients with NP-C suffer pharmacorefractory seizures associated with ongoing neurodegeneration, KDT might be beneficial. The concomitant use of miglustat and KDT in patients with NP-C has not been reported. CASE PRESENTATION: We describe our experience in a now 17-year-old female with NP-C manifest early in childhood who has been successfully and continuously treated with miglustat and KDT in a palliative care setting for 3y. Although the neurodegeneration of NP-C progressed, she benefited from a reduction in seizure activity, fewer hospital stays related to seizure exacerbation, and increased alertness. CONCLUSION: KDT could be safely deployed in our patient with NP-C, in whom its effects have been beneficial. Generally KDT is demonstratedly efficacious in patients with epilepsy and IMD. It reduces seizure activity and medication requirements and confers neuroprotection. Intracellular cholesterol trafficking and regulation of cholesterol biosynthesis are impaired in NP-C, which may prompt caution with respect to dietary lipid intake.

Assessment of the Clinical Impact of a Liver-Specific, BCAA-Enriched Diet in Major Liver Surgery.

BACKGROUND: The relationship between nutrition and liver disease is relevant for the outcome after surgery. Patients with liver cirrhosis characteristically show protein-energy malnutrition with decreased levels of branched-chain amino acids (BCAA) and increased levels of aromatic amino acids. MATERIALS AND METHODS: We conducted a prospective controlled clinical trial including 57 patients after liver transplantation or major liver resection surgery in order to test the effect of early postoperative nutrition on the outcome and nutrition profile of these patients. The test group received a dietetic program composed of ingredients naturally rich in BCAA (BCAA group), and the control group received standard hospital meals. Patient survival, liver function tests, subjective well-being, and a nutritional status including amino acid profiles were analyzed immediately and 14 days after major liver surgery (secondary end points). General health and well-being were assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (primary end point). RESULTS: In-depth analysis of amino acid profiles was performed for patients undergoing liver resection (n = 21) and liver transplantation (n = 36). Interestingly, amino acid profiles did not correlate with body mass index or the Model for End-Stage Liver Disease score. Patients scheduled for liver transplantation showed significantly lower levels of BCAA pretransplant compared to patients undergoing liver resection. Patients in the liver resection subgroup were more likely to benefit from the BCAA cuisine in terms of significantly higher food intake and subjective rating. The clinical liver function tests, however, did not show statistical difference between the BCAA group and the control group in the examination period of 14 days. CONCLUSION: Our specifically designed BCAA-enriched diet resulted in greater patient satisfaction and compliance with nutrition. A larger trial or longer-term follow-up may be required to identify an effect on survival, recovery, surgical complications, protein profiles, and amino acid profiles.

Treatment recommendations in long-chain fatty acid oxidation defects: consensus from a workshop.

Published data on treatment of fatty acid oxidation defects are scarce. Treatment recommendations have been developed on the basis of observations in 75 patients with long-chain fatty acid oxidation defects from 18 metabolic centres in Central Europe. Recommendations are based on expert practice and are suggested to be the basis for further multicentre prospective studies and the development of approved treatment guidelines. Considering that disease complications and prognosis differ between different disorders of long-chain fatty acid oxidation and also depend on the severity of the underlying enzyme deficiency, treatment recommendations have to be disease-specific and depend on individual disease severity. Disorders of the mitochondrial trifunctional protein are associated with the most severe clinical picture and require a strict fat-reduced and fat-modified (medium-chain triglyceride-supplemented) diet. Many patients still suffer acute life-threatening events or long-term neuropathic symptoms despite adequate treatment, and newborn screening has not significantly changed the prognosis for these severe phenotypes. Very long-chain acyl-CoA dehydrogenase deficiency recognized in neonatal screening, in contrast, frequently has a less severe disease course and dietary restrictions in many patients may be loosened. On the basis of the collected data, recommendations are given with regard to the fat and carbohydrate content of the diet, the maximal length of fasting periods and the use of l-carnitine in long-chain fatty acid oxidation defects.

Management and outcome in 75 individuals with long-chain fatty acid oxidation defects: results from a workshop.

At present, long-chain fatty acid oxidation (FAO) defects are diagnosed in a number of countries by newborn screening using tandem mass spectrometry. In the majority of cases, affected newborns are asymptomatic at time of diagnosis and acute clinical presentations can be avoided by early preventive measures. Because evidence-based studies on management of long-chain FAO defects are lacking, we carried out a retrospective analysis of 75 patients from 18 metabolic centres in Germany, Switzerland, Austria and the Netherlands with special regard to treatment and disease outcome. Dietary treatment is effective in many patients and can prevent acute metabolic derangements and prevent or reverse severe long-term complications such as cardiomyopathy. However, 38% of patients with very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency had intermittent muscle weakness and pain despite adhering to therapy. Seventy-six per cent of patients with disorders of the mitochondrial trifunctional protein (TFP)-complex including long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency, had long-term myopathic symptoms. Of these, 21% had irreversible peripheral neuropathy and 43% had retinopathy. The main principle of treatment was a fat-reduced and fat-modified diet. Fat restriction differed among patients with different enzyme defects and was strictest in disorders of the TFP-complex. Patients with a medium-chain fat-based diet received supplementation of essential long-chain fatty acids. l-Carnitine was supplemented in about half of the patients, but in none of the patients with VLCAD deficiency identified by newborn screening. In summary, in this cohort the treatment regimen was adapted to the severity of the underlying enzyme defect and thus differed among the group of long-chain FAO defects.

Stroke-like episodes in propionic acidemia caused by central focal metabolic decompensation.

Propionic acidemia caused by propionyl-CoA carboxylase deficiency frequently leads to neurologic complications. Herein we report an eleven-year-old patient with propionic acidemia having three stroke-like episodes during a period of 13 months characterized by acute reversible hemiplegia and vegetative symptoms like bradycardia or drowsiness. No biochemical signs of severe metabolic decompensation were detectable in plasma. At all three episodes, EEG was not indicative for status epilepticus, but in the acute episode it showed slowing of background activity emphasized on one side. MRI revealed reversible hyperintensities in cortical grey matter and basal ganglia. During the third episode a lumbar puncture was done in parallel with venous puncture. Concentrations of glutamine (902 micromol/L), glycine (24 micromol/L) and alanine (78 micromol/L) were elevated in CSF. In plasma glycine (1 859 micromol/L) and alanine (608 micromol/L) concentrations were also elevated, whereas the glutamine (458 micromol/L) concentration was normal. CSF/plasma ratios were elevated for glutamine (1.97) and alanine (0.13) and normal for glycine (0.01). We assume that the stroke-like episodes in our patient may be caused by an acute focal cerebral metabolic decompensation, which is detectable by unspecific changes in MRI and by measuring amino acids and lactate in CSF versus plasma.

Epilepsy in patients with propionic acidemia.

Propionic acidemia (PA) is an autosomal recessively inherited defect of propionyl-CoA carboxylase with an incidence of approximately 1:50 000. There are few reports on the occurrence of EEG findings and development of epilepsy in patients with PA. Retrospectively, the data of 17 patients with PA from one Italian and four Austrian centers were evaluated concerning EEG findings and the development of epilepsy. Nine patients showed a disturbance of background activity, as well as epileptiform discharges. All nine patients with pathological EEG discharges developed seizures compatible with the definition of symptomatic epilepsy. Five of these nine patients showed fever induced seizures at the beginning. Two of them suffered from symptomatic absence epilepsy. Six of the nine patients with seizures were treated with antiepileptic drugs (AED), which were tolerated without side-effects. Four patients showed photosensitivity, which so far has never been reported in PA. We hypothesize that patients with PA are prone to cortical dysfunction caused by one or several pathological metabolites - leading to changes in background and epileptiform activity with a high manifestation rate of clinical seizures.

The relation of cerebrospinal fluid and plasma glycine levels in propionic acidaemia, a 'ketotic hyperglycinaemia'.

The characteristic elevation of plasma glycine concentrations observed in propionic acidaemia (PA) and other 'ketotic hyperglycinaemias' has been attributed to secondary inhibition of the hepatic glycine cleavage system (GCS) by accumulating CoA derivatives of branched-chain amino acid metabolites. In nonketotic hyperglycinaemia (NKH), cerebrospinal fluid (CSF) and plasma glycine levels and their ratio are increased due to primary deficiency of central nervous system (CNS) as well as hepatic GCS. Whether the GCS in the CNS is also inhibited in PA is unclear, as there are scant data available on CSF glycine levels in this disorder. We studied the relation of CSF and plasma glycine levels in 6 paired samples from 4 PA patients, including one PA patient with bacterial meningitis who underwent ventriculoperitoneal shunting and multiple CSF analyses (n = 26). In contrast to the CSF glycine levels which were generally elevated in all four PA patients, the CSF/plasma glycine concentration ratios in paired samples were normal (0.016-0.029), with the exception of a single sample (0.132) with extremely high CSF protein concentration (2010 mg/L) during the course of meningitis indicating a disturbed blood-brain barrier. This finding of normal CSF/plasma glycine ratio in PA suggests that the observed elevations of CSF glycine levels are a reflection of the concurrent hyperglycinaemia resulting from secondary inhibition of hepatic GCS, but that brain GCS is not affected, in contrast to the situation in NKH. The neurological sequelae in PA are therefore unlikely to be related to disturbed glycine metabolism.

Amino acids in CSF and plasma in hyperammonaemic coma due to arginase1 deficiency.

UNLABELLED: We report the CSF and plasma amino acid concentrations and their ratios in a male patient with arginase1 deficiency with an unusual early presentation at 34 days of age. He developed hyperammonaemic coma (ammonia >400 µmol/L; normal <90 µmol/L) on postnatal day 35. CSF and plasma concentrations were assayed by ion-exchange chromatography on day 36. Arginine was increased both in plasma (971 µmol/L; controls (mean ± 2SD) 50 ± 42) and in CSF (157 µmol/L; controls 19 ± 8.6), resulting in a normal CSF/plasma ratio of 0.16 (controls 0.41 ± 0.26). Interestingly, glutamine was disproportionately high in CSF (3114 µmol/L; controls 470 ± 236) but normal in plasma (420 µmol/L; controls 627 ± 246); the ratio exceeded unity (7.4; controls 0.76 ± 0.31). The CSF/plasma ratios of most neutral amino acids were elevated but not those of the imino- and of the dibasic amino acids lysine and ornithine. The mechanism leading to the increase of most neutral amino acids in brain is not known. CONCLUSION: A normal glutamine in plasma does not exclude an increased concentration in CSF; it could be useful to ascertain by MRS that a high CSF glutamine concentration truly reflects a high concentration in brain tissue for better understanding its pathogenesis.

Effect of valproic acid treatment on body composition, leptin and the soluble leptin receptor in epileptic children.

PURPOSE: The aim of the study was to determine the influence of valproic acid (VPA) treatment on leptin, the soluble leptin receptor (sOB-R), the sOB-R/leptin ratio, body composition and insulin resistance in epileptic children. METHODS: A cross-sectional cohort study was conducted at the Medical University Innsbruck, Austria. Children >6 years with idiopathic epilepsy and antiepileptic drug therapy since at least six months were eligible. Leptin concentration, the sOB-R, the sOB-R/leptin ratio, body composition and glucose homeostasis were determined. RESULTS: 87 children (median [range] age 12.8 years [6.0-18.6]) were on treatment with VPA, 55 (12.3 years [6.4-18.3]) on other AEDs, comprising the non-VPA group. VPA-treated children had higher leptin concentrations, body-mass-index standard-deviation score (SDS), body fat (each p<0.001), serum insulin concentrations (p=0.014) and homeostasis model assessment (HOMA) index (p=0.009), as well as a lower sOB-R/leptin ratio (p<0.001) when compared to the non-VPA group. Overweight VPA-treated children showed lower sOB-R concentrations and a lower sOB-R/leptin ratio (each p<0.001) as well as higher body fat and leptin levels (each p<0.001) compared to lean VPA-treated children. CONCLUSION: VPA monotherapy was associated with higher body weight, body fat and serum leptin concentrations as well as impaired glucose homeostasis. Low sOB-R concentrations and a low sOB-R/leptin ratio in overweight VPA-treated patients might contribute to disturbances in glucose homeostasis and to the development of the metabolic syndrome in these children later in life.

Sports in LCHAD Deficiency: Maximal Incremental and Endurance Exercise Tests in a 13-Year-Old Patient with Long-Chain 3-Hydroxy Acyl-CoA Dehydrogenase Deficiency (LCHADD) and Heptanoate Treatment.

Exercise and subsequent catabolism is a potential trigger for creatine kinase (CK) concentration increase (rhabdomyolysis) in patients with LCHADD, therefore we evaluated the clinical and biochemical stability under physical exertion conditions at the age of 13 years in a currently 14-year-old LCHADD patient treated with heptanoate.LCHADD was diagnosed during first decompensation at age 20 months. In the following 2 years, the patient had several episodes of rhabdomyolysis. Heptanoate 0.5-1 g/kg/day was started at 4 years, with no further CK elevations since. He is clinically stable, has retinopathy without vision impairment or polyneuropathy. Maximal incremental and endurance exercise tests were performed to evaluate both clinical and metabolic stability during and after exertion.Physical fitness was adequate for age (maximum blood lactate 7.0 mmol/L, appropriate lactate performance curve, maximum heart rate of 196 bpm, maximum power 139 Watt = 2.68 Watt/kg body weight). There were no signs of clinical (muscle pain, dark urine) or metabolic derangement (stable CK, acyl carnitine profiles, blood gas analyses) - neither after maximal incremental nor endurance exertion.This case illustrates that both under maximal incremental and endurance exertion, clinical and biochemical parameters remained stable in this currently 14-year-old LCHADD patient receiving heptanoate treatment.

Peripheral neuropathy as the sole initial finding in three children with infantile metachromatic leukodystrophy.

Metachromatic leukodystrophy (MLD) is a progressive white matter disease caused by arylsulfatase A deficiency. Demyelination in the nervous system is detected by cerebral magnetic resonance imaging (MRI) and neurophysiological studies. We present three children with infantile MLD, who had difficulties in standing and walking with absent reflexes. Protein levels in cerebral spinal fluid (CSF) were elevated and nerve conduction studies revealed slowing down of motor nerve conduction velocity. Initial cerebral MRIs showed no white matter changes. Consecutively, all three children developed clinical symptoms of neurodegenerative disease. Follow-up MRI and arylsulfatase A testing led to diagnosis of MLD. We conclude, that in young children who present with an acute/subacute demyelinating polyneuropathy, MLD is a differential diagnosis.