A novel mutation in sphingosine-1-phosphate lyase causing congenital brain malformation.

INTRODUCTION: Recently recessive mutations in sphingosine-1-phosphate lyase (SGPL1) have been published as a cause of syndromic congenital nephrotic syndrome with adrenal insufficiency. We have identified a case with fetal hydrops and brain malformations due to a mutation in SGPL1. CASE REPORT: We report a patient presenting with severe fetal hydrops, congenital nephrotic syndrome and adrenal calcifications. MRI imaging showed generalized cortical atrophy with simplified gyral pattern and hypoplastic temporal lobes as well as cerebellar hypoplasia and hyperintensity in the pons. The boy deceased at 6 weeks of age. Via whole exome sequencing, we identified a novel homozygous frameshift mutation c.1233delC (p.Phe411Leufs∗56) in SGPL1. CONCLUSION: In our patient, we describe a novel mutation in sphingosine-1-phosphate lyase (SGPL1) leading to severe brain malformation. Neurodevelopmental phenotypes have been reported earlier, but not described in detail. To this end, we present a review on all published SGPL1-mutations and genotype-phenotype correlations focusing on neurodevelopmental outcomes. We hypothesized on the severe neurological phenotypes, which might be due to disruption of neuronal autophagy. Mutations in SGPL1 shall be considered in the differential diagnosis of fetal hydrops as well as congenital brain malformations and neuropathies.

Multicenter study on the effectiveness of the pre-epiglottic baton plate for airway obstruction and feeding problems in Robin sequence.

BACKGROUND: Treatment of Robin sequence is often either invasive or of unproven effectiveness. The pre-epiglottic baton plate (PEBP) is a well-studied alternative, yet is not widely applied internationally. We report on a prospective 3-center cohort study investigating this treatment. Based on an agreed protocol, parents of infants with Robin sequence referred to participating centers were offered enrollment, which involved taking a maxillary cast followed by endoscopy to fit the plate and sleep studies to monitor its effectiveness. Recordings were centrally analyzed by sleep specialists blinded to timing and center. Primary outcome was the mixed-obstructive apnea index, defined as the number of such apneas/h of sleep; secondary outcomes included the desaturation index to <80% pulse oximeter saturation and weight gain. RESULTS: Of 75 infants referred, 49 could be included; 1 center failed to perform appropriate sleep studies. Within a mean hospitalization of 3 weeks, the mixed-obstructive apnea index decreased (median; interquartile range) from 15.9 (6.3-31.5) to 2.3 (1.2-5.4); it decreased further to 0.7 (0.1-2.4) in the 32 infants who had a successful 3-month follow-up sleep study performed. The desaturation index normalized (from 0.38 (0-2.7) to 0.0 (0-0.1)). Mean standard deviation score for weight remained unchanged between admission and follow-up, while the proportion of tube-fed infants decreased from 74 to 14%. CONCLUSIONS: This prospective multi-center cohort study confirms retrospective audits on the effectiveness of PEBP treatment in improving upper airway obstruction and feeding problems, the main clinical problems of infants with Robin sequence. International collaboration is required to compare this with other treatment approaches. TRIAL REGISTRATION: Number NCT02266043 , Registered 30/09/2014; registered partially retrospectively.

Disorders of fatty acid oxidation and autosomal recessive polycystic kidney disease-different clinical entities and comparable perinatal renal abnormalities.

BACKGROUND: Differential diagnosis of prenatally detected hyperechogenic and enlarged kidneys can be challenging as there is a broad phenotypic overlap between several rare genetic and non-genetic disorders. Metabolic diseases are among the rarest underlying disorders, but they demand particular attention as their prognosis and postnatal management differ from those of other diseases. METHODS: We report two cases of cystic, hyperechogenic and enlarged kidneys detected on prenatal ultrasound images, resulting in the suspected diagnosis of autosomal recessive polycystic kidney disease (ARPKD). Postnatal clinical course and work-up, however, revealed early, neonatal forms of disorders of fatty acid oxidation (DFAO) in both cases, namely, glutaric acidemia type II, based on identification of the novel, homozygous splice-site mutation c.1117-2A > G in the ETFDH gene, in one case and carnitine palmitoyltransferase II deficiency in the other case. RESULTS: Review of pre- and postnatal sonographic findings resulted in the identification of some important differences that might help to differentiate DFAO from ARPKD. In DFAO, kidneys are enlarged to a milder degree than in ARPKD, and the cysts are located ubiquitously, including also in the cortex and the subcapsular area. Interestingly, recent studies have pointed to a switch in metabolic homeostasis, referred to as the Warburg effect (aerobic glycolysis), as one of the underlying mechanisms of cell proliferation and cyst formation in cystic kidney disease. DFAO are characterized by the inhibition of oxidative phosphorylation, resulting in aerobic glycolysis, and thus they do resemble the Warburg effect. We therefore speculate that this inhibition might be one of the pathomechanisms of renal hyperproliferation and cyst formation in DFAO analogous to the reported findings in ARPKD. CONCLUSIONS: Neonatal forms of DFAO can be differentially diagnosed in neonates with cystic or hyperechogenic kidneys and necessitate immediate biochemical work-up to provide early metabolic management.

Mendeliome sequencing enables differential diagnosis and treatment of neonatal lactic acidosis.

BACKGROUND: Neonatal lactic acidosis can be associated to severe inborn errors of metabolism. Rapid identification of the underlying disorder may improve the clinical management through reliable counseling of the parents and adaptation of the treatment. METHODS: We present the case of a term newborn with persistent hypoglycemia on postnatal day 1, who developed severe lactic acidosis, aggravating under intravenous glucose administration. Routine metabolic investigations revealed elevated pyruvate and lactate levels in urine, and magnetic resonance spectroscopy showed a lactic acid peak and decreased N-acetylaspartate levels. Mitochondrial disorders, e.g., pyruvate dehydrogenase (PDH) deficiency, were the major differential diagnoses. However, both hypoglycemia and the elevated lactate to pyruvate ratio in serum (=55.2) were not typical for PDH deficiency. We used "Mendeliome sequencing", a next-generation sequencing approach targeting all genes which have been previously linked to single-gene disorders, to obtain the correct diagnosis. RESULTS: On day 27 of life, we identified a homozygous stop mutation in the PDHX gene, causing pyruvate dehydrogenase E3-binding protein deficiency. After starting the ketogenic diet, the infant recovered and is showing delayed but progressive development. CONCLUSIONS: Mendeliome sequencing was successfully used to disentangle the underlying cause of severe neonatal lactic acidosis. Indeed, it is one of several targeted sequencing approaches that allow rapid and reliable counseling of the parents, adaptation of the clinical management, and renunciation of unnecessary, potentially invasive and often costly diagnostic measures.

The pericardial reflection and the tip of the central venous catheter - topographical analysis in stillborn babies.

BACKGROUND: Central venous cannulation is widely used in neonatal critical care. Pericardial tamponade caused by vessel wall perforation can occur if the catheter tip induces extravasation at the level of the pericardium. OBJECTIVE: To investigate the level of the superior pericardial reflection in stillborn babies. MATERIALS AND METHODS: We dissected 20 bodies (11 female, mean gestational age 33 6/7 weeks, range 25-43 weeks), with careful opening of the thoracic area. After injecting contrast medium into the pericardial sac, we introduced a catheter through the right internal jugular vein. We then took radiographs to analyse the relationship between visual osseous landmarks and the pericardium. RESULTS: Mean distance between the pericardial reflection at its upper end and the first thoracic vertebra was 1.3 cm (standard deviation [SD]: 0.3 cm) and did not extend over the 3rd intercostal space. The mean distance from the entry of the superior vena cava into the pericardial sac and the 1st thoracic vertebra was 2.3 cm (SD: 0.5). CONCLUSION: The upper end of the pericardial reflection in neonates at autopsy lies below the middle of the 3rd thoracic vertebra. The tip of an upper inserted catheter should not extend below the level of the 3rd intercostal space.

Increased Risk of Interstitial Lung Disease in Children with a Single R288K Variant of ABCA3.

The ABCA3 gene encodes a lipid transporter in type II pneumocytes critical for survival and normal respiratory function. The frequent ABCA3 variant R288K increases the risk for neonatal respiratory distress syndrome among term and late preterm neonates, but its role in children's interstitial lung disease has not been studied in detail. In a retrospective cohort study of 228 children with interstitial lung disease related to the alveolar surfactant system, the frequency of R288K was assessed and the phenotype of patients carrying a single R288K variant further characterized by clinical course, lung histology, computed tomography and bronchoalveolar lavage phosphatidylcholine PC 32:0. Cell lines stably transfected with ABCA3-R288K were analyzed for intracellular transcription, processing and targeting of the protein. ABCA3 function was assessed by detoxification assay of doxorubicin, and the induction and volume of lamellar bodies. We found nine children with interstitial lung disease carrying a heterozygous R288K variant, a frequency significantly higher than in the general Caucasian population. All identified patients had neonatal respiratory insufficiency, recovered and developed chronic interstitial lung disease with intermittent exacerbations during early childhood. In vitro analysis showed normal transcription, processing, and targeting of ABCA3-R288K, but impaired detoxification function and smaller lamellar bodies. We propose that the R288K variant can underlie interstitial lung disease in childhood due to reduced function of ABCA3, demonstrated by decelerated detoxification of doxorubicin, reduced PC 32:0 content and decreased lamellar body volume.

Efficacy and safety of cyclic pyranopterin monophosphate substitution in severe molybdenum cofactor deficiency type A: a prospective cohort study.

BACKGROUND: Molybdenum cofactor deficiency (MoCD) is characterised by early, rapidly progressive postnatal encephalopathy and intractable seizures, leading to severe disability and early death. Previous treatment attempts have been unsuccessful. After a pioneering single treatment we now report the outcome of the complete first cohort of patients receiving substitution treatment with cyclic pyranopterin monophosphate (cPMP), a biosynthetic precursor of the cofactor. METHODS: In this observational prospective cohort study, newborn babies with clinical and biochemical evidence of MoCD were admitted to a compassionate-use programme at the request of their treating physicians. Intravenous cPMP (80-320 µg/kg per day) was started in neonates diagnosed with MoCD (type A and type B) following a standardised protocol. We prospectively monitored safety and efficacy in all patients exposed to cPMP. FINDINGS: Between June 6, 2008, and Jan 9, 2013, intravenous cPMP was started in 16 neonates diagnosed with MoCD (11 type A and five type B) and continued in eight type A patients for up to 5 years. We observed no drug-related serious adverse events after more than 6000 doses. The disease biomarkers urinary S-sulphocysteine, xanthine, and urate returned to almost normal concentrations in all type A patients within 2 days, and remained normal for up to 5 years on continued cPMP substitution. Eight patients with type A disease rapidly improved under treatment and convulsions were either completely suppressed or substantially reduced. Three patients treated early remain seizure free and show near-normal long-term development. We detected no biochemical or clinical response in patients with type B disease. INTERPRETATION: cPMP substitution is the first effective therapy for patients with MoCD type A and has a favourable safety profile. Restoration of molybdenum cofactor-dependent enzyme activities results in a greatly improved neurodevelopmental outcome when started sufficiently early. The possibility of MoCD type A needs to be urgently explored in every encephalopathic neonate to avoid any delay in appropriate cPMP substitution, and to maximise treatment benefit. FUNDING: German Ministry of Education and Research; Orphatec/Colbourne Pharmaceuticals.

Novel deletions affecting the MEG3-DMR provide further evidence for a hierarchical regulation of imprinting in 14q32.

The imprinted region on chromosome 14q32 harbors several maternally or paternally expressed genes as well as two DMRs (differentially methylated regions), the IG-DMR and the MEG3-DMR, which both act as imprinting control centers. Genetic aberrations affecting the imprinted gene cluster in 14q32 result in distinct phenotypes, known as maternal or paternal uniparental disomy 14 phenotypes (upd(14)mat, upd(14)pat). In both syndromes, three types of molecular alterations have been reported: uniparental disomy 14, deletions and epimutations. In contrast to uniparental disomy and epimutations, deletions affecting regulatory elements in 14q32 are associated with a high-recurrence risk. Based on two single deletion cases a functional hierarchy of the IG-DMR as a regulator for the methylation of the MEG3-DMR has been proposed. We have identified two novel deletions of maternal origin spanning the MEG3-DMR, but not the IG-DMR in patients with upd(14)pat syndrome, one de novo deletion of 165 kb and another deletion of 5.8 kb in two siblings. The 5.8 kb deletion was inherited from the phenotypically normal mother, who carries the deletion in a mosaic state on her paternal chromosome 14. The methylation at both DMRs was investigated by quantitative next generation bisulfite sequencing and revealed normal methylation patterns at the IG-DMR in all patients with the exception of certain CpG dinucleotides. Thus, we could confirm that deletions of the MEG3-DMR does not generally influence the methylation pattern of the IG-DMR, which strengthens the hypothesis of a hierarchical structure and distinct functional properties of the two DMRs.

Thiamin status of premature infants assessed by measurement of thiamin diphosphate in whole blood.

Premature infants constitute a risk group for thiamin deficiency but only little is known about their thiamin status. The aim of the present study was to investigate the thiamin status of premature infants by determination of thiamin diphosphate (TDP) and to identify risk factors for low TDP concentrations. In a prospective, longitudinal study TDP was determined by HPLC in whole blood in the first days of life and approximately every 2 weeks. Demographical data, weight gain, type of nutrition and thiamin intake were recorded. A total of 111 premature infants were included at the Children's Hospital of the University of Cologne, Germany from May 2009 until December 2010 and 222 blood samples were analysed. TDP concentrations showed an age-dependent decline (age 0­10 d, mean TDP = 110.6 ng/ml; age 11­20 d, mean TDP = 95.4 ng/ml; age 21­103 d, mean TDP = 33.6 ng/ml). There was no significant difference between males and females. Young gestational age and low birth weight were associated with low TDP concentrations. No infant was diagnosed with thiamin deficiency. The current nutritional regimen in our hospital did not lead to thiamin deficiency in the study cohort. Further research is required to evaluate how TDP concentrations are regulated in premature infants.

Remifentanil and propofol for weaning of mechanically ventilated pediatric intensive care patients.

Mechanically ventilated pediatric intensive care patients usually receive an analgesic and sedative to keep them comfortable and safe. However, common drugs like fentanyl and midazolam have a long context sensitive half time, resulting in prolonged sedation and an unpredictable extubation time. Children often awake slowly and struggle against the respirator, although their respiratory drive and their airway reflexes are not yet sufficient for extubation. In this pilot study, we replaced fentanyl and midazolam at the final phase of the weaning process with remifentanil and propofol. Twenty-three children aged 3 months-10 years were enrolled. Remifentanil and propofol revealed throughout excellent or good weaning conditions with rapid transition from hypnosis to the development of regular spontaneous breathing, airway protective reflexes, and an appropriate level of alertness. Extubation time following discontinuation of the remifentanil and propofol infusion was only 24 ± 20 min (5-80 min). We conclude that the combination of remifentanil and propofol is a promising option to improve the weaning conditions of pediatric intensive care patients. Randomized controlled trials are needed to compare remifentanil and propofol with conventional weaning protocols.

Symptomatic cerebral oedema during treatment of diabetic ketoacidosis: effect of adjuvant octreotide infusion.

INTRODUCTION: A potentially lethal complication of diabetic ketoacidosis (DKA) in children is brain oedema, whether caused by DKA itself or by the therapeutic infusion of insulin and fluids. CASE PRESENTATION: A 10-year old previously healthy boy with DKA became unconscious and apnoeic due to cerebral oedema (confirmed by abnormal EEG and CT-scan) during treatment with intravenous fluids (36 ml/h) and insulin (0.1 units/kg/h). He was intubated and artificially ventilated, without impact on EEG and CT-scan. Subsequently, adjuvant infusion of octreotide was applied (3.5 µg/kg/h), suppressing growth hormone (GH) and IGF-1 production and necessitating the insulin dose to be reduced to 0.05 - 0.025 units/kg/h. The brain oedema improved and the boy made a full recovery. CONCLUSION: Co-therapy with octreotide was associated with a favourable outcome in the present patient with DKA and cerebral oedema. Whether this could be ascribed to the effects of octreotide on the insulin requirement or on the GH/IGF-axis remains to be elucidated.

Determination of thiamin diphosphate in whole blood samples by high-performance liquid chromatography--a method suitable for pediatric diagnostics.

An improved and easy to use method for the determination of thiamin diphosphate (TDP) in 100 microl of whole blood was developed. The small sample volume makes it possible to assess the nutritional status of vitamin B(1) in infants and even in preterm infants. Sample preparation comprises the extraction of TDP from whole blood by hemolysis, protein precipitation with trichloroacetic acid, and subsequent centrifugation. Potassium ferricyanide is used for pre-column derivatization of TDP to its fluorescent thiochrome derivative. Chromatographic separation was carried out using a reversed-phase column and an isocratic elution which consisted of a phosphate buffer and acetonitrile. TDP was detected fluorimetrically and quantified by external standardization. Method validation showed a high precision, almost complete recovery, and a high sensitivity. The lower limit of detection and the lower limit of quantification were 0.2 ng/ml and 4 ng/ml, respectively. Linearity was demonstrated over the expected concentration range of 4-400 ng/ml. In conclusion, we present a convenient HPLC method for the determination of TDP which is precise, sensitive and suitable for pediatric diagnostics.

Early surfactant in spontaneously breathing with nCPAP in ELBW infants--a single centre four year experience.

OBJECTIVE: To evaluate whether the experience with a method to administer surfactant during spontaneous breathing with nasal continuous positive airway pressure (nCPAP) as primary respiratory support in infants with respiratory distress syndrome (RDS) influences the frequency of its use and affects the outcome of patients. METHODS: All inborn extremely low birthweight (ELBW) infants treated after introduction of the method were retrospectively studied (n=196). The entire observational period was divided into four periods (periods 1-4) and compared with a control period (period 0) (n=51). Primary respiratory support, demographics, prenatal risks and outcomes were compared. RESULTS: There were no changes in demographics or prenatal risks over time. The choice of nCPAP as initial airway management significantly increased from 69% to 91% and for nCPAP with surfactant from 75% to 86%. The rate of nCPAP failure decreased from 46% to 25%. Survival increased significantly between periods 0 and 1 from 76% to 90% and survival without bronchopulmonary dysplasia (BPD) rose from 65% to 80%. No changes in nonpulmonary outcomes were observed. CONCLUSION: The success of nCPAP increased with increasing use of nCPAP with surfactant. Simultaneously, mortality decreased without deterioration of other outcomes indicating that the use of surfactant in spontaneous breathing with nCPAP could be beneficial.

Early administration of surfactant in spontaneous breathing with nCPAP: feasibility and outcome in extremely premature infants (postmenstrual age

BACKGROUND: Spontaneous breathing supported by nasal continuous positive airway pressure (nCPAP) is thought to have some advantages compared with mechanical ventilation in extremely premature infants. In addition, early or prophylactic surfactant administration has been shown to be superior to delayed use. A strategy to combine these two principles was tested in our neonatal intensive care unit (NICU). The aim of this feasibility study was to describe the procedure and compare short-term results with a historical control. METHODS: The study took place in a level III NICU. In the observational period all extremely premature infants with clinical signs of moderate to severe respiratory distress syndrome despite nCPAP received 100 mg.kg(-1) of a natural surfactant preparation via an intratracheal catheter during spontaneous breathing. In the historical control period those infants were intubated and ventilated to receive surfactant. RESULTS: Twenty-nine of 42 infants fulfilled the criteria and were treated with the new approach. In five cases ventilation with manual bag was necessary after administration of surfactant but all infants could be retransferred to nCPAP within a few minutes. Ten infants were intubated later during the first 3 days. Mortality was 7% in the group of infants treated in this way and 12% in all infants treated during the observational period. Mortality was 35% in the historical control period. Morbidity was within ranges reported by other authors. CONCLUSIONS: Surfactant administration during nCPAP is feasible. First results indicate that early complications are rare. This warrants a prospective randomized trial.

Gender-based differences in children with sepsis and ARDS: the ESPNIC ARDS Database Group.

Male gender predisposes to severe sepsis and septic shock. This effect has been ascribed to higher levels of testosterone. The ESPNIC ARDS database was searched, to determine if there was evidence of a similar male preponderance in severe sepsis in prepubertal patients in spite of low levels of male sex hormones at this age. A total of 72 patients beyond neonatal age up to 8 years of age with sepsis were identified. The male/female (M/F) ratio was 1.7 (1.0;2.7) and differed significantly from non-septic ARDS patients in this age group [n = 209; M/F = 1.0 (0.8;1.3)]. The highest M/F-ratio was observed in the first year of life. The gender-ratio was the same as reported in adult patients with sepsis. In infants between 1 month and 12 months of age, the ratio was 2.8 (1.2;6.1) (Chi2= 5.6; P< 0.01), in children from 1 year to 8 years of age it was 1.2 (0.7;2.2) (n.s.). In a subgroup of patients with severe sepsis or septic shock, caused by other bacteria than Neisseria meningitidis, the M/F-ratio was 2.1 (1.2;3.6) (Chi2= 4.9; P<0.05), while in patients with meningococcal sepsis (n=20) the M/F-ratio was 1.0 (0.4;2.3). In prepubertal ARDS patients with sepsis an increased frequency of male patients is found, comparable to adults. No male preponderance exists in patients with ARDS due to meningococcal septic shock. Since levels of testosterone and other sex hormones are extremely low at this age, we conclude that factors others than testosterone are involved in the male preponderance in severe sepsis.

Treatment with bovine surfactant in severe acute respiratory distress syndrome in children: a randomized multicenter study.

OBJECTIVE: To determine whether bovine surfactant given in cases of severe pediatric acute respiratory distress syndrome (ARDS) improves oxygenation. DESIGN: Single-center study with 19 patients, followed by a multicenter randomized comparison of surfactant with a standardized treatment algorithm. Primary endpoint PaO(2)/FIO(2) at 48 h, secondary endpoints: PaO(2)/FIO(2) at 2, 4, 12, and 24 h, survival, survival without rescue, days on ventilator, subgroups analyzed by analysis of variance to identify patients who might benefit from surfactant. SETTING: Multicenter study in 19 reference centers for ARDS. PATIENTS: Children after the 44th postconceptional week and under 14 years old, admitted for at least 4 h, ventilated for 12-120 h, and without heart failure or chronic lung disease. In the multicenter study 35 patients were recruited; 20 were randomized to the surfactant group and 15 to the nonsurfactant group. Decreasing recruitment of patients led to a preliminary end of this study. INTERVENTIONS: Administration of 100 mg/kg bovine surfactant intratracheally under continuous ventilation and PEEP, as soon as the PaO(2)/FIO(2) ratio dropped to less than 100 for 2 h (in the pilot study increments of 50 mg/kg as long as the PaO(2)/FIO(2) did not increase by 20%). A second equivalent dose within 48 h was permitted. RESULTS: In the pilot study the PaO(2)/FIO(2) increased by a mean of 100 at 48 h (n=19). A higher PaO(2)/FIO(2) ratio was observed in the surfactant group 2 h after the first dose (58 from baseline vs. 9), at 48 h there was a trend towards a higher ratio (38 from baseline vs. 22). The rate of rescue therapy was significantly lower in the surfactant group. Outcome criteria were not affected by a second surfactant dose (n=11). A significant difference in PaO(2)/FIO(2) in favor of surfactant at 48 h was found in the subgroup with an initial PaO(2)/FIO(2) ratio higher than 65 and in patients without pneumonia. CONCLUSIONS. Surfactant therapy in severe ARDS improves oxygenation immediately after administration. This improvement is sustained only in the subgroup of patients without pneumonia and that with an initial PaO(2)/FIO(2) ratio higher than 65