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Purpose:Hypoglycemia is a common and life-threatening complication in type 1 diabetes mellitus (T1DM) patients. Current guidelines recommend glucagon for treating hypoglycemia in out-of-hospital settings; however, glucagon is reportedly underused in such patients. We conducted a doctor-oriented, questionnaire-based survey of pediatricians and physicians to determine the glucagon prescription rate and identify the reason(s) for its underuse in T1DM patients.Methods:A questionnaire was mailed to 415 pediatricians and 200 physicians employed at 66 facilities with >100 general wards throughout Hyogo, Japan. The following variables were surveyed: doctor’s specialty, glucagon prescription rate, familiarity with glucagon use guidelines, barriers to prescribing glucagon, and attitude changes after education.Results:After 16 doctors were found to have retired, 599 doctors were enrolled; 305 (187 pediatricians and 118 physicians) returned a completed questionnaire. In all, 45 pediatricians and 104 physicians were treating T1DM patients, of whom 24% and 28% reported prescribing glucagon, respectively. The guideline familiarity rate among pediatricians was lower than that among physicians. The major barrier to prescribing glucagon was the complex preparation procedure required by patients/caregivers. More than half of the doctors who did not prescribe glucagon began doing so after being educated about the guidelines.Conclusion:The glucagon prescription rate was low among both pediatricians and physicians in Japan.

In Japan, carnitine palmitoyltransferase II (CPTII) deficiency has been included as one of the primary target diseases in the expanded newborn mass screening program since 2018. However, many cases of the severe infantile hepatocardiomuscular form of CPTII deficiency showed severe neurodevelopmental delay or sudden death, which indicated that management of CPTII deficiency in the acute phase remains to be studied in detail. Herein, we discuss two cases diagnosed by newborn mass screening. Patient 1 was under strict clinical management from the neonatal period, with >20 admissions in 14 months, while Patient 2 was managed using a relatively relaxed approach, with only 2 admissions in the same period. Patient 1 showed normal development; however, Patient 2 expired at the age of 1 year 2 months. To develop strategies for preventing sudden deaths in patients with CPTII deficiency, this retrospective study focused on detailed clinical management practices and biochemical findings during the acute phase. We also investigated the correlation between conventional biomarkers (such as creatine kinase) and long-chain acylcarnitines. We propose that strict monitoring and immediate medical attention, even in case of slight fever or minor abdominal symptoms, can help prevent sudden death in patients with CPTII deficiency. Considering the higher morbidity rate of such patients, strict and acute management of CPTII deficiency cannot be overemphasized.

Very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency, a condition in which the body is unable to break down long-chain fatty acids properly, is the most common fatty acid oxidation disorder in Japan. Tandem mass spectrometry has been used in newborn screening (NBS), allowing the detection of patients with VLCAD deficiency even before symptoms manifest. However, tandem mass spectrometry has a high false positive rate. We investigated the clinical characteristics of patients with false positive results for tetradecenoyl acylcarnitine (C14:1). This case-control study used data collected between the 1st of January 2014 and the 31st of March 2019. The case group was defined as patients having levels of both C14:1 and C14:1/C2 ratio higher than cut-off levels in the first newborn mass screening, who were eventually diagnosed as false positives by attending doctors at Kobe University Hospital, Palmore Hospital, or Kakogawa Central City Hospital in Japan. The control group comprised 100 patients randomly selected from the three facilities. The false positive group included 17 cases, and the control group contained 300 patients. The demographics of each group did not show any significant differences in sex, body weight at birth, Cesarean section rate, complete breastfeeding rate, or the number of feedings per day. However, the change in body weight at the sampling day of NBS in the false positive and control groups was −10.2%, and − 4.6%, respectively, showing a statistically significant difference (p, Highlights • VLCAD deficiency is the most common fatty acid oxidation disorder in Japan. • Tandem mass spectrometry during newborn screening facilitates its early detection. • Tandem mass spectroscopy has a high false positive rate. • Here, clinical characteristics of false-positive patients were investigated. • False-positive patients showed significant loss of weight during newborn screening.

Mitochondrial trifunctional protein (TFP) deficiency is an inherited metabolic disorder of mitochondrial fatty-acid oxidation. Isolated long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency is often reported in Caucasian countries due to a common mutation. However, the molecular and clinical basis of complete TFP deficiency has not been extensively reported. In this study, 14 Japanese cases (13 families) with complete TFP deficiency, including 9 previously reported cases, were analyzed to clarify the clinical and molecular characteristics of TFP deficiency. The clinical types of the 14 patients were as follows: 12 cases of neonatal (n=7) or myopathic (n=5) types and 2 cases of intermediate type. Peripheral neuropathy was found in four cases and hypocalcemia due to hypoparathyroidism, which is rarely reported in Caucasian patients, had developed in four cases. Maternal hemolysis, elevated liver enzymes and low platelet count syndrome and acute fatty liver of pregnancy were noted in two and one mothers, respectively. Fourteen mutations were identified in 26 alleles in Japanese patients, including two novel mutations (HADHA: c.361C>T, and HADHA-HADHB: g.26233880_ 26248855del), although no common mutations were found. This study suggests that the molecular and clinical aspects of Japanese patients with TFP deficiencies differ from those of Caucasian patients.

Introduction We evaluated the effects of bezafibrate (BEZ) on β-oxidation in fibroblasts obtained from patients with glutaric acidemia type II (GA2) of various clinical severities using an in vitro probe (IVP) assay. Methods Cultured fibroblasts from 12 patients with GA2, including cases of the neonatal-onset type both with and without congenital anomalies (the prenatal- and neonatal-onset forms, respectively), the infantile-onset, and the myopathic forms, were studied. The IVP assay was performed by measuring acylcarnitines (ACs) in the cell culture medium of fibroblasts incubated with palmitic acid for 96 h in the presence of 0–800 μM BEZ using tandem mass spectrometry. Results The IVP assay showed that 100 μM BEZ markedly reduced the level of palmitoylcarnitine (C16) in the neonatal-onset, infantile-onset, and myopathic forms of GA2, either increasing or maintaining a high level of acetylcarnitine (C2), which serves as an index of energy production via β-oxidation. In the prenatal-onset form, although a small reduction of C16 was also observed in the presence of 100 μM BEZ, the level of C2 remained low. At concentrations higher than 100 μM, BEZ further decreased the level of ACs including C16, but a concentration over 400 μM decreased the level of C2 in most cases. Discussion BEZ at 100 μM was effective for all GA2 phenotypes except for the prenatal-onset form, as a reduction of C16 without deterioration of C2 is considered to indicate improvement of β-oxidation. The effects of higher doses BEZ could not be estimated by the IVP assay but might be small or nonexistent.

Germline intragenic mutations in the GNAS locus result in pseudohypoparathyroidism type 1a (PHP1a) and related conditions. Nearly half of the previously reported GNAS intragenic mutations were structural variants, including 3 tandem duplications of 12-25 bp. However, the precise mutation spectrum and the genomic basis of GNAS structural variants remain to be clarified. Here, we report a de novo 50-bp tandem duplication in GNAS (c.723_772dup50, p.Glu259Leufs*29) identified in a patient with typical clinical features of PHP1a. The mutant transcript was predicted to undergo mRNA decay or encode a nonfunctional protein. The 2 breakpoints of the duplication shared a 1-bp microhomology but were not associated with long homology or nucleotide stretches. We also examined the breakpoint structures of 3 previously reported GNAS duplications and found that 1 had a structure similar to that of our case, while the remaining 2 had blunt-ended breakpoints without microhomologies. In silico analyses revealed that the GNAS-flanking region was not enriched with repeats, palindromes, noncanonical DNA motifs, or GC content. This study expands the mutation spectrum of GNAS and provides the first indication that GNAS intragenic structural variants are induced by multiple processes, including nonhomologous end-joining and/or microhomology-mediated break-induced replication, independently of known rearrangement-inducing DNA features.

Background Glutaryl carnitine (C5DC) in dried blood spots is used as a biomarker for glutaric aciduria type 1 (GA-1) screening. C5DC, however, is the only screening marker for this condition, and various pathological conditions may interfere with C5DC metabolism. Recently, C5DC elevation has been reported in cases of renal insufficiency. Method Five patients who were positive for GA-1 on newborn screening with tandem mass spectrometry between September 2012 and March 2015 at Kobe University Hospital were enrolled in this study. Results GA-1 was not confirmed on urinary organic acids analysis in any of the patients. C5DC decreased immediately in four patients, but one patient, who had high C5DC for at least 4 months, was diagnosed with bilateral renal hypoplasia. Conclusion In the case of persistently elevated C5DC, renal insufficiency should be considered as a differential diagnosis.

Background: Duchenne muscular dystrophy (DMD) is a fatal progressive muscle-wasting disease caused by mutations in the DMD gene. Dilated cardiomyopathy is the leading cause of death in DMD; therefore, further understanding of this complication is essential to reduce morbidity and mortality. Methods: A common null variant (R577X) in the ACTN3 gene, which encodes α-actinin-3, has been studied in association with muscle function in healthy individuals; however it has not yet been examined in relationship to the cardiac phenotype in DMD. In this study, we determined the ACTN3 genotype in 163 patients with DMD and examined the correlation between ACTN3 genotypes and echocardiographic findings in 77 of the 163 patients. Results: The genotypes 577RR(RR), 577RX(RX) and 577XX(XX) were identified in 13 (17%), 44 (57%) and 20 (26%) of 77 patients, respectively. We estimated cardiac involvement-free survival rate analyses using Kaplan-Meier curves. Remarkably, the left ventricular dilation (> 55 mm)-free survival rate was significantly lower in patients with the XX null genotype (P < 0.01). The XX null genotype showed a higher risk for LV dilation (hazard ratio 9.04). Conclusions: This study revealed that the ACTN3 XX null genotype was associated with a lower left ventricular dilation-free survival rate in patients with DMD. These results suggest that the ACTN3 genotype should be determined at the time of diagnosis of DMD to improve patients’ cardiac outcomes.

Very long-chain acyl-coenzyme A dehydrogenase deficiency (VLCADD, OMIM 201475) is a congenital fatty acid oxidation disorder. Individuals with VLCADD should avoid catabolic states, including strenuous exercise and long-term fasting; however, such conditions are required when undergoing surgery. The perioperative management of VLCADD in infants has rarely been reported and details regarding the transition of serum biomarkers reflecting catabolic status have not been disclosed. Herein, we present the perioperative clinical and biological data of cryptorchidism in a 1.5-year-old boy with VLCADD. The patient was diagnosed through newborn screening and his clinical course was very stable. Genetic testing of ACADVL revealed compound heterozygous variants c.506 T > C (p.Met169Thr) and c.606-609delC (p.L216*). The enzyme activity of the patient with VLCAD was only 20% compared to that of healthy control. Left orchiopexy for the pediatric cryptorchidism was planned and performed at 1 and a half year of age. Induction anesthesia involved thiopental, fentanyl and rocuronium. The glucose infusion rate was maintained above 6.6 mg/kg/min starting the day before surgery until the operation was completed. Anesthesia was maintained with sevoflurane at approximately 2%. The serum concentration of tetradecenoylcarnitine were stable during the operation, ranging between 0.08 and 0.19 μM (cutoff, Highlights • Catabolic biomarker status details during surgery in infants with VLCADD is lacking. • We performed uneventful surgical intervention in a 1.5-year-old patient with VLCADD. • Serum levels of tetradecenoyl carnitine remained stable during the operation. • Serum biomarkers creatine kinase, 3-hydroxybutyrate, and free fatty acid remained similarly unchanged. • These findings will be beneficial in the management of VLCADD.

Introduction An increasing number of adult patients have been diagnosed with fatty acid β-oxidation disorders with the rising use of diagnostic technologies. In this study, clinical, biochemical, and molecular characteristics of 2 Japanese patients with adult-onset glutaric acidemia type II (GA2) were investigated and compared with those of pediatric cases. Methods The patients were a 58-year-old male and a 31-year-old male. In both cases, episodes of myopathic symptoms, including myalgia, muscle weakness, and liver dysfunction of unknown cause, had been noted for the past several years. Muscle biopsy, urinary organic acid analysis (OA), acylcarnitine (AC) analysis in dried blood spots (DBS) and serum, immunoblotting, genetic analysis, and an in vitro probe acylcarnitine (IVP) assay were used for diagnosis and investigation. Results In both cases, there was no obvious abnormality of AC in DBS or urinary OA, although there was a increase in medium- and long-chain ACs in serum; also, fat deposits were observed in the muscle biopsy. Immunoblotting and gene analysis revealed that both patients had GA2 due to a defect in electron transfer flavoprotein dehydrogenase (ETFDH). The IVP assay indicated no special abnormalities in either case. Conclusion Late-onset GA2 is separated into the intermediate and myopathic forms. In the myopathic form, episodic muscular symptoms or liver dysfunction are primarily exhibited after later childhood. Muscle biopsy and serum (or plasma) AC analysis allow accurate diagnosis in contrast with other biochemical tests, such as analysis of AC in DBS, urinary OA, or the IVP assay, which show fewer abnormalities in the myopathic form compared to intermediate form.

Carnitine palmitoyltransferase II (CPT-2) deficiency, an autosomal recessive disorder of fatty acid oxidation, can be detected by newborn screening using tandem mass spectrometry (TMS). Our case was a boy born at 38 weeks and 6 days of gestation via normal vaginal delivery; his elder sister was affected with CPT-2 deficiency. Acylcarnitine (AC) was analyzed in both dried blood spots (DBS) and serum 2 h after birth to determine whether the boy was also affected. His C16 and C18:1 AC levels in DBS were in the normal range, while his serum long-chain AC levels were marginally increased but lower than those of his sister. After the samples were taken, he was treated with glucose infusion to prevent any catabolism for 2 days. On day 4, the long-chain AC levels in both DBS and serum obtained were higher than those on day 0 and were equivalent to those of his sister. Genetic testing confirmed the presence of the same mutation found in his sister, a homozygous F383Y mutation in the CPT2 gene, thus leading to the diagnosis of CPT-2 deficiency. The sample for TMS should be taken between days 1 and 7. If the sample is not obtained at an appropriate time, correct diagnosis may not be made, as in our case. Although early diagnosis is required, samples taken within 24 h after birth should not be used for TMS.

BACKGROUND Mechanical insufflation-exsufflation (MI-E) is necessary for noninvasive management of respiratory clearance in patients with neuromuscular disorders (NMDs). Its utility has been proven, and the technique is recommended in a number of international guidelines for the management of patients with NMDs. However, the clearance of thick secretions adhering to the tracheobronchial walls could be problematic when these patients suffer from respiratory tract infections. To improve the effectiveness of the noninvasive technique, a novel device combining MI-E with high frequency oscillation (HFO) has been developed. However, the efficacy of HFO therapy in NMDs has not been well studied. OBJECTIVE The aim of this study was to elucidate the effect of MI-E combined with HFO for mucus removal in NMD patients. To evaluate its efficacy, changes in transcutaneous oxygen saturation (SpO2), which may predict intratracheal mucus removal, will be measured before and after use of MI-E. METHODS This is a single-center, nonblinded, nonrandomized prospective study that will enroll 5 subjects hospitalized in Kobe University Hospital owing to respiratory tract infection. All subjects will receive MI-E therapy a few times daily and will receive HFO every other day, for 6 days. Before and after MI-E use, SpO2 will be obtained and the change in SpO2 (ΔSpO2) between MI-E with and without HFO will be calculated. For every subject, the average of ΔSpO2 with or without HFO will be obtained and the null hypothesis that there is a mean change of 0 in the SpO2 between MI-E with and without HFO will be tested using the paired t test. If the treatment with HFO is found to be statistically significantly superior to the treatment without HFO, the study will conclude that HFO addition is more efficacious than no HFO addition. RESULTS A total of 2 subjects have already been recruited and enrolled in this study as of August 2018. CONCLUSIONS This unique protocol will assess the efficacy of adding HFO to MI-E during the acute phase of respiratory tract infection in patients with NMDs. INTERNATIONAL REGISTERED REPOR DERR1-10.2196/12102

Patients with severe hypophosphatasia (HPP) develop osteogenic impairment with extremely low alkaline phosphatase (ALP) activity, resulting in a fatal course during infancy. Mesenchymal stem cells (MSCs) differentiate into various mesenchymal lineages, including bone and cartilage. The efficacy of allogeneic hematopoietic stem cell transplantation for congenital skeletal and storage disorders is limited, and therefore we focused on MSCs for the treatment of HPP. To determine the effect of MSCs on osteogenesis, we performed multiple infusions of ex vivo expanded allogeneic MSCs for two patients with severe HPP who had undergone bone marrow transplantation (BMT) from asymptomatic relatives harboring the heterozygous mutation. There were improvements in not only bone mineralization but also muscle mass, respiratory function, and mental development, resulting in the patients being alive at the age of 3. After the infusion of MSCs, chimerism analysis of the mesenchymal cell fraction isolated from bone marrow in the patients demonstrated that donor-derived DNA sequences existed. Adverse events of BMT were tolerated, whereas those of MSC infusion did not occur. However, restoration of ALP activity was limited, and normal bony architecture could not be achieved. Our data suggest that multiple MSC infusions, following BMT, were effective and brought about clinical benefits for patients with lethal HPP. Allogeneic MSC-based therapy would be useful for patients with other congenital bone diseases and tissue disorders if the curative strategy to restore clinically normal features, including bony architecture, can be established.

Background Carnitine palmitoyltransferase (CPT) II deficiency is one of the most common forms of mitochondrial fatty acid oxidation disorder (FAOD). However, newborn screening (NBS) for this potentially fatal disease has not been established partly because reliable indices are not available. Methods We diagnosed CPT II deficiency in a 7-month-old boy presenting with hypoglycemic encephalopathy, which apparently had been missed in the NBS using C16 and C18:1 concentrations as indices. By referring to his acylcarnitine profile from the NBS, we adopted the (C16 + C18:1)/C2 ratio (cutoff 0.62) and C16 concentration (cutoff 3.0 nmol/mL) as alternative indices for CPT II deficiency such that an analysis of a dried blood specimen collected at postnatal day five retroactively yielded the correct diagnosis. Thereafter, positive cases were assessed by measuring (1) the fatty acid oxidation ability of intact lymphocytes and/or (2) CPT II activity in the lysates of lymphocytes. The diagnoses were then further confirmed by genetic analysis. Results The disease was diagnosed in seven of 21 newborns suspected of having CPT II deficiency based on NBS. We also analyzed the false-negative patient and five symptomatic patients for comparison. Values for the NBS indices of the false-negative, symptomatic patient were lower than those of the seven affected newborns. Although it was difficult to differentiate the false-negative patient from heterozygous carriers and false-positive subjects, the fatty acid oxidation ability of the lymphocytes and CPT II activity clearly confirmed the diagnosis. Among several other indices proposed previously, C14/C3 completely differentiated the seven NBS-positive patients and the false-negative patient from the heterozygous carriers and the false-positive subjects. Genetic analysis revealed 16 kinds of variant alleles. The most prevalent, detected in ten alleles in nine patients from eight families, was c.1148T > A (p.F383Y), a finding in line with those of several previous reports on Japanese patients. Conclusions These findings suggested that CPT II deficiency can be screened by using (C16 + C18:1)/C2 and C16 as indices. An appropriate cutoff level is required to achieve adequate sensitivity albeit at the cost of a considerable increase in the false-positive rate, which might be reduced by using additional indices such as C14/C3.

Background: Mechanical insufflation-exsufflation (MI-E) is necessary for noninvasive management of respiratory clearance in patients with neuromuscular disorders (NMDs). Its utility has been proven, and the technique is recommended in a number of international guidelines for the management of patients with NMDs. However, the clearance of thick secretions adhering to the tracheobronchial walls could be problematic when these patients suffer from respiratory tract infections. To improve the effectiveness of the noninvasive technique, a novel device combining MI-E with high frequency oscillation (HFO) has been developed. However, the efficacy of HFO therapy in NMDs has not been well studied. Objective: The aim of this study was to elucidate the effect of MI-E combined with HFO for mucus removal in NMD patients. To evaluate its efficacy, changes in transcutaneous oxygen saturation (SpO2), which may predict intratracheal mucus removal, will be measured before and after use of MI-E. Methods: This is a single-center, nonblinded, nonrandomized prospective study that will enroll 5 subjects hospitalized in Kobe University Hospital owing to respiratory tract infection. All subjects will receive MI-E therapy a few times daily and will receive HFO every other day, for 6 days. Before and after MI-E use, SpO2 will be obtained and the change in SpO2 (ΔSpO2) between MI-E with and without HFO will be calculated. For every subject, the average of ΔSpO2 with or without HFO will be obtained and the null hypothesis that there is a mean change of 0 in the SpO2 between MI-E with and without HFO will be tested using the paired t test. If the treatment with HFO is found to be statistically significantly superior to the treatment without HFO, the study will conclude that HFO addition is more efficacious than no HFO addition. Results: A total of 2 subjects have already been recruited and enrolled in this study as of August 2018. Conclusions: This unique protocol will assess the efficacy of adding HFO to MI-E during the acute phase of respiratory tract infection in patients with NMDs. International Registered Report Identifier (IRRID): DERR1-10.2196/12102

Sivelestat sodium (sivelestat), a neutrophil elastase inhibitor, is used to treat acute respiratory distress syndrome (ARDS). We report two cases that developed elevated C5-acylcarnitine (C5-AC) levels following treatment with sivelestat. Case 1 was a 14-day-old female infant born at 25 weeks and 1 day of gestation who was treated with sivelestat for the prophylaxis of Wilson-Mikity syndrome soon after birth. Isovaleric acidemia (IVA) was suspected based on a newborn screening using tandem mass spectrometry (MS/MS). Her C5-AC level was elevated to 4.49 μM (cut-off,1.0) after treatment with sivelestat. Case 2 was a 4-year-old female with pneumocystis pneumonia that developed during chemotherapy for disseminated medulloblastoma. Sivelestat was given for the complication of ARDS. Her C5-AC level increased (1.09 μM) after eight days of treatment with sivelestat.In both cases, IVA was ruled out because isovalerylglycine was not observed in the urinary organic acid analysis. Case 1 was associated with carnitine deficiency (C0 9.16 μM; reference value, 10-60). Liquid chromatography-MS/MS confirmed elevated pivaloylcarnitine (PVC) in both cases.Similar to antibiotics containing pivalic acid (PVA), sivelestat contains PVA, which has the potential to cause secondary carnitine deficiency. In addition, elevated PVC can lead to false positive findings of IVA in newborns screened using MS/MS.