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Hereditary pyropoikilocytosis is a subtype of hereditary elliptocytosis because of biallelic mutations of SPTA1, SPTB, and EPB41. The authors present a proband with neonatal jaundice and hemolytic anemia, with poikilocytosis in the blood film. Targeted next-generation sequencing identified Q267del trans to the αLELY allele in SPTA1. In addition, the proband presented coexisting Gilbert syndrome as determined by homozygous mutation of UGT1A1. Investigation of 13 relatives and his sibling revealed that only his sibling showed the same phenotype and genotype as the proband. This is the first report of molecular confirmation of coexisting hereditary pyropoikilocytosis and Gilbert syndrome and a novel mutation in SPTA1.

Objectives Progressive familial intrahepatic cholestasis type 1 (PFIC-1), an autosomal recessive disorder, is characterized by cholestasis, jaundice, and refractory pruritus. In some patients with PFIC-1, liver cirrhosis and end-stage liver disease develop and lead to liver transplantation (LT). In this observational study, we sought to clarify the long-term outcomes of LT for PFIC-1 and predictors of favorable outcomes. Methods The study cohort constituted 12 patients with PFIC-1 who had undergone living donor liver transplantation (LDLT) during the previous 3 decades (1990-2019). We compared the clinical manifestations and type of ATP8B1 mutations between patients in whom LDLT had been successful and those in whom it had been unsuccessful. Results LDLT failed in 5 of the 12 patients and the 25-year survival rate was 58%. Comparison of physical growth after LDLT revealed significant retardation of stature in patients in whom LDLT had been unsuccessful; these patients developed severe and persistent diarrhea. ATP8B1 genotypic analysis revealed that frameshifting, splicing, and large deletion mutations occurred more commonly in successful cases, whereas missense mutations occurred more frequently in unsuccessful cases. No mutations were identical in the 2 groups. Conclusions These results suggest an association between post-LT outcomes and extrahepatic manifestations, especially intestinal function. Further investigation of correlations between ATP8B1 genotypes and intestinal function could help to identify patients with PFIC-1 who will achieve favorable post-LT outcomes.

Adenosine triphosphatase phospholipid transporting 8B1 (ATP8B1) deficiency, an ultrarare autosomal recessive liver disease, includes severe and mild clinical forms, referred to as progressive familial intrahepatic cholestasis type 1 (PFIC1) and benign recurrent intrahepatic cholestasis type 1 (BRIC1), respectively. There is currently no practical method for determining PFIC1 or BRIC1 at an early disease course phase. Herein, we assessed the feasibility of developing a diagnostic method for PFIC1 and BRIC1. A nationwide Japanese survey conducted since 2015 identified 25 patients with cholestasis with ATP8B1 mutations, 15 of whom agreed to participate in the study. Patients were divided for analysis into PFIC1 (n = 10) or BRIC1 (n = 5) based on their disease course. An in vitro mutagenesis assay to evaluate pathogenicity of ATP8B1 mutations suggested that residual ATP8B1 function in the patients could be used to identify clinical course. To assess their ATP8B1 function more simply, human peripheral blood monocyte-derived macrophages (HMDMs) were prepared from each patient and elicited into a subset of alternatively activated macrophages (M2c) by interleukin-10 (IL-10). This was based on our previous finding that ATP8B1 contributes to polarization of HMDMs into M2c. Flow cytometric analysis showed that expression of M2c-related surface markers cluster of differentiation (CD)14 and CD163 were 2.3-fold and 2.1-fold lower (95% confidence interval, 2.0-2.5 for CD14 and 1.7-2.4 for CD163), respectively, in patients with IL-10-treated HMDMs from PFIC1 compared with BRIC1. Conclusion: CD14 and CD163 expression levels in IL-10-treated HMDMs may facilitate diagnosis of PFIC1 or BRIC1 in patients with ATP8B1 deficiency.

Marked improvements have been achieved in the survival of extremely low birth weight infants, but survival rates and prognoses of extremely small infants with birth weights ≤500 g remain poor. The aim of this study was to clarify long-term outcomes for surviving infants with birth weights ≤500 g. Methods: The study population comprised fetuses of gestational age ≥22 weeks, expected live- or stillbirth weight ≤500 g, and birth date between 2003 and 2012. Developmental assessments were performed prospectively at 3 years old. Results: Data were obtained for 21 fetuses, including 10 live births and 11 stillbirths. Of the 10 live births, median gestational age was 25.2 weeks (range, 22.4–27.1 weeks), median birth weight was 426 g (range, 370–483 g), and two neonates died before discharge. One infant with severe asphyxia died within 12 h and another infant with Down syndrome died at 34 days. The survival rate was thus 80%. All surviving infants were small for gestational age. Seven of the 8 surviving infants (88%) weighed less than 2500 g at a corrected age of 40 weeks. Seven infants were available for developmental assessments at 3 years old. One infant could not be followed. Two of those seven infants (29%) showed normal development, three infants (42%) showed mild neurodevelopmental disability, and two infants (29%) showed severe neurodevelopmental disability. One infant had periventricular leukomalacia and cerebral palsy. Two of the seven infants (29%) had short stature (

Progressive familial intrahepatic cholestasis type 1 (PFIC1), a rare inherited recessive disease resulting from a genetic deficiency in ATP8B1, progresses to liver failure. Because of the difficulty of discriminating PFIC1 from other subtypes of PFIC based on its clinical and histological features and genome sequencing, an alternative method for diagnosing PFIC1 is desirable. Herein, we analyzed human peripheral blood monocyte-derived macrophages (HMDM) and found predominant expression of ATP8B1 in interleukin-10 (IL-10)-induced M2c, a subset of alternatively activated macrophages. SiRNA-mediated depletion of ATP8B1 in IL-10-treated HMDM markedly suppressed the expression of M2c-related surface markers and increased the side scatter (SSC) of M2c, likely via impairment of the IL-10/STAT3 signal transduction pathway. These phenotypic features were confirmed in IL-10-treated HMDM from four PFIC1 patients with disease-causing mutations in both alleles, but not in those from four patients with other subtypes of PFIC. This method identified three PFIC1 patients in a group of PFIC patients undiagnosed by genome sequencing, an identical diagnostic outcome to that achieved by analysis of liver specimens and in vitro mutagenesis studies. In conclusion, ATP8B1 deficiency caused incomplete polarization of HMDM into M2c. Phenotypic analysis of M2c helps to identify PFIC1 patients with no apparent disease-causing mutations in ATP8B1., Graphical Abstract Image 1, Highlights • ATP8B1, a causal gene of PFIC1, was expressed in IL-10-induced M2c, a subset of alternatively activated macrophages. • ATP8B1 deficiency caused incomplete polarization of HMDM into M2c, likely via impairment of IL-10/STAT3 signaling. • Phenotypic analysis of M2c helps to discriminate PFIC1 from other pediatric liver diseases undiagnosed by genomic analysis. PFIC1, a rare inherited recessive disease resulting from a genetic deficiency in ATP8B1, progresses to liver failure. PFIC1 shares many clinical and histological features with other subtypes of PFIC, but differs in its therapeutic options. Because genome sequencing in patients with a clinical diagnosis of PFIC cannot always identify disease-causing mutations, an alternative method for diagnosing PFIC1 is desirable. We identified expression of ATP8B1 in IL-10-induced M2c, a subset of macrophages, and demonstrated its contribution to normal phenotypic expression of M2c. The phenotypic analysis of M2c helps to discriminate PFIC1 from other pediatric liver diseases undiagnosed by genomic analysis.

Background: We encountered 7 Japanese patients with bile acid synthesis disorders (BASD) over 21 years between 1996 and 2017. Diagnoses were made by bile acid and genetic analyses. We gave low-dose, long-term chenodeoxycholic acid (CDCA) treatment to 5 of the patients, who had 3β-hydroxy-Δ 5 -C 27 -steroid dehydrogenase/isomerase (3β-HSD) deficiency (n=3) or Δ 4 -3-oxosteroid 5β-reductase (5β-reductase) deficiency (n=2). Another patient with the latter diagnosis whose bile acid analyses had mitigating features was maintained on ursodeoxycholic acid according to parental preferences and now remains healthy after discontinuation of treatment. A patient with oxysterol 7α-hydroxylase deficiency developed liver failure and fully recovered after successful liver transplantation. We used clinical records to clarify long-term outcome and value of CDCA in the other patients. Efficacy of CDCA treatment was evaluated in the 5 patients given a low dose (5 to 10 mg/kg/day) for a long term. Results: Medians with ranges of current patient ages and duration of CDCA treatment are10 years (8 to 43) and 10 years (8 to 21), respectively. All 7 patients, who had homozygous or compound heterozygous mutations in the HSD3B7 , SRD5B1 , or CYP7B1 gene, are currently in good health without liver dysfunction. In the 5 patients with CDCA treatment, hepatic function gradually improved following initiation. No adverse effects were noted. Conclusions: We concluded that low-dose CDCA treatment is effective in 3β-HSD deficiency and 5β-reductase deficiency, as cholic acid has been in other countries. BASD carry a good prognosis following early diagnosis and initiation of long-term, low-dose CDCA treatment.

A 60-year-old male, who exhibited finger tremors, obnubilation, and hyperammonemia (409 μg/dL), was admitted to our hospital. Initially, we suspected that a portosystemic shunt had caused his hyperammonemia. However, his symptoms did not improve after balloon-occluded retrograde transvenous obliteration. He was subsequently found to have some peculiar eating habits, including a fondness for bean curd and peanuts, and an aversion to alcohol and sweets. Furthermore, marked citrullinemia (454.2 nmol/mL) was revealed, which led us to suspect adult-onset type II citrullinemia (CTLN2). DNA analysis of the patient and his mother, son, and daughter confirmed that he was homozygous for the c.852_855del mutation in the SLC25A13 gene, and his relatives were heterozygous for the c.852_855del mutation, which led to a definitive diagnosis. A low-carbohydrate diet and the administration of l-arginine ameliorated his symptoms. It is important to be aware that CTLN2 can occur in elderly patients. Thus, patients who exhibit symptoms of CTLN2 should be interviewed about their dietary habits and subjected to plasma amino acid analysis. In this report, we consider the metabolic disorders seen in citrin deficiency and the associated compensatory mechanisms in relation to the clinical features and treatment of CTLN2.

The bile salt export pump is expressed at the canalicular membrane of hepatocytes and mediates biliary excretion of bile salts. 4-Phenylbutyrate (4 PB), a drug used to treat ornithine transcarbamylase deficiency, has been found to increase the hepatocanalicular expression of bile salt export pump. The beneficial effects of 4-phenylbutyrate therapy have been reported for patients with progressive familial intrahepatic cholestasis, an inherited autosomal recessive liver disease. This is the first study to show the therapeutic effect of 4 PB in a preterm infant with cholestasis and liver fibrosis. The preterm infant had severe cholestasis with jaundice and failure to thrive refractory to ursodeoxycholic acid. Histology indicated giant cell hepatitis, cholestasis, and severe fibrosis. Bile salt export pump immunostaining showed lower expression than in a control. Oral 4 PB was started at a daily dose of 200 mg/kg/day. After the start of 4 PB therapy, cholestasis improved.

Background Persistent patent ductus arteriosus (PDA) is a frequent complication in preterm infants. Single nucleotide polymorphisms (SNP) in several genes, including angiotensin II receptor, type 1 (AGTR1), transcription factor AP-2 beta (TFAP2B) and tumor necrosis factor receptor-associated factor 1 (TRAF1), have been reported to be associated with PDA in preterm infants. The aim of this study was to evaluate the relationships between PDA in preterm infants and polymorphisms in AGTR1, TFAP2B and TRAF1 in the Japanese population. Methods The subjects consisted of 107 preterm infants with gestational age

We report the case of a patient born with extreme muscle hypotonia, respiratory failure, and slightly elevated serum levels of lactic acid. Histochemical examination and mitochondrial respiratory chain enzyme activities of a muscle biopsy specimen revealed reduced activities of complexes Ⅰ, Ⅲ, and Ⅳ, diagnostic of mitochondrial respiratory chain disorder. Hypertrophic cardiomyopathy developed as a complication and additional therapy was administered at 3 months after birth. He was able to be discharged to home on applied home mechanical ventilation with tracheotomy at 1 year old. The patient survived until 4 years and 10 months of age, upon which he died of bronchitis. Early-onset mitochondrial respiratory chain disorder shows very poor prognosis and long-term survival has not been reported. Prompt assessment of mitochondrial respiratory chain enzyme activities is necessary for the diagnosis of congenital nonspecific multiple-organ failure, and early intervention may achieve better prognosis for mitochondrial respiratory chain disorder.

We report a case of nemaline myopathy with KLHL40 mutation, presenting as congenital totally locked-in state. At birth, a male patient developed hydrops fetalis, which was diagnosed based on the generalized edema and pleural effusion and could perform no significant spontaneous movements. His eyes were open, without blinking, and the eyeballs were locked in the midposition. He could not express his intentions by vocalization or moving his trunk, extremities, facial muscles, mouth, eyelids, or eyeballs in response to ambient events or personal interactions. Electrophysiological tests and neuroimaging revealed no evidence of visual or auditory impairment that might indicate a lack of sensory perception, and no evidence of impaired consciousness or intellectual disorder(s) that might prevent him from recognizing ambient events or expressing his intentions. He subsequently died at 4 years of age. Our case highlights the fact that severe congenital neuromuscular disorders can present as congenital totally locked-in state, and that special attention should be provided to these patients.

Aim We evaluated combined genetic analyses with targeted next-generation sequencing (NGS), multiplex ligation probe amplification (MLPA) of Jagged1 (JAG1) genes and microarray comparative genomic hybridisation (CGH) in subjects with Alagille syndrome, incomplete clinical features of Alagille syndrome and biliary atresia. Methods Subjects recruited from April 2013 to December 2015 underwent a targeted NGS analysis, including JAG1 and Notch homolog 2 (NOTCH2). If no mutations were detected in JAG1 or NOTCH2, or if copy number variations were suggested by the NGS analysis, we performed an MLPA analysis of JAG1. We also performed a microarray CGH analysis with whole-exon deletion detected by the MLPA analysis. Results We analysed 30 subjects with Alagille syndrome, nine with incomplete Alagille syndrome and 17 with biliary atresia and detected pathogenic mutations in JAG1 or NOTCH2 in 24/30 subjects with Alagille syndrome and in 4/9 subjects with incomplete Alagille syndrome. No pathogenic mutations were detected in subjects with biliary atresia. The frequency of JAG1 mutations was: single nucleotide variants (51.9%), small insertion or deletion (29.6%) and gross deletion (18.5%). Conclusion Combined genetic analyses achieved efficient diagnostic yields for subjects with Alagille syndrome and incomplete Alagille syndrome. This article is protected by copyright. All rights reserved.

Background Congenital hypogonadotropic hypogonadism (CHH) is classified as Kallmann syndrome (KS) with anosmia/hyposmia or normosmic (n)CHH. Here, we investigated the genetic causes and phenotype-genotype correlations in Japanese patients with CHH. Methods We enrolled 22 Japanese patients with CHH from 21 families (18 patients with KS and 4 with nCHH) and analyzed 27 genes implicated in CHH by next-generation and Sanger sequencing. Results We detected 12 potentially pathogenic mutations in 11 families, with three having a mutation in ANOS1 (X-linked recessive); three and four having a mutation in FGFR1 and CHD7, respectively (autosomal dominant); and one having two TACR3 mutations (autosomal recessive). Among four patients with KS carrying a CHD7 mutation, one had perceptive deafness and two had a cleft lip/palate. Conclusions The frequency of CHH genes in the Japanese was compatible with previous reports, except that CHD7 mutations might be more common. Furthermore, partial phenotype-genotype correlations were demonstrated in our cohort.

Background Constitutive activation of the PI3K-AKT-mTOR pathway (mTOR pathway) underlies megalencephaly in many patients. Yet, prevalence of the involvement of the PI3K-AKT-mTOR pathway in patients with megalencephaly remains to be elucidated, and molecular diagnosis is challenging. Here, we have successfully established a combination of genetic and biochemical methods for diagnosis of mTOR pathway-associated megalencephaly, and have attempted to delineate the clinical characteristics of the disorder. Methods Thirteen patients with an increased head circumference and neurological symptoms participated in the study. To evaluate the activation of the mTOR pathway, we performed western blot analysis to determine the expression levels of phosphorylated S6 ribosomal protein (phospho-S6 protein) in lymphoblastoid cell lines from 12 patients. Multiplex targeted sequencing analysis for 15 genes involved in the mTOR pathway was performed on 12 patients, and whole-exome sequencing was performed on one additional patient. Clinical features and MRI findings were also investigated. Results We identified pathogenic mutations in six (AKT3, 1 patient; PIK3R2, 2 patients; PTEN, 3 patients) of the 13 patients. Increased expression of phospho-S6 protein was demonstrated in all five mutation-positive patients in whom western blotting was performed, as well as in three mutation-negative patients. Developmental delay, dysmorphic facial features were observed in almost all patients. Syndactyly/polydactyly and capillary malformations were not observed, even in patients with AKT3 or PIK3R2 mutations. There were no common phenotypes or MRI findings among these patients. Conclusions A combination of genetic and biochemical methods successfully identified mTOR pathway involvement in nine of 13 (approximately 70%) patients with megalencephaly, indicating a major contribution of the pathway to the pathogenesis of megalencephaly. Our combined approach could be useful to identify patients who are suitable for future clinical trials using an mTOR inhibitor.

Objective To clarify the clinical, pathologic, and genetic features of neonatal Dubin-Johnson syndrome. Study design Ten patients with neonatal Dubin-Johnson syndrome were recruited from 6 pediatric centers in Japan between September 2013 and October 2016. Clinical and laboratory course, macroscopic and microscopic liver findings, and molecular genetic findings concerning ATP-binding cassette subfamily C member 2 (ABCC2) were retrospectively and prospectively examined. Results All neonates exhibited cholestasis, evident as prolonged jaundice with or without acholic stools and elevations of serum direct bilirubin as well as γ-glutamyltransferase or total bile acids. Only 38% (3 of 8) of patients who underwent liver biopsy showed a grossly black liver or melanin-like pigment deposits in hepatocytes; their biopsies were performed in early infancy. Immunohistochemically, all liver specimens showed no expression of multidrug resistance-associated protein 2 but increased expression of the bile salt export pump protein. Homozygous or compound heterozygous pathogenic variants of ABCC2 were identified in all patients, representing 11 distinct pathogenic variants including 2 not previously reported. Conclusions Immunohistochemical staining of the liver for multidrug resistance-associated protein 2 and molecular genetic analysis of ABCC2 are crucial for accurate diagnosis of neonatal Dubin-Johnson syndrome.

平成27年度

Persistent patent ductus arteriosus (PDA) is a frequent complication in preterm infants. Single nucleotide polymorphisms (SNP) in several genes, including angiotensin II receptor, type 1 (AGTR1), transcription factor AP-2 beta (TFAP2B) and tumor necrosis factor receptor-associated factor 1 (TRAF1), have been reported to be associated with PDA in preterm infants. The aim of this study was to evaluate the relationships between PDA in preterm infants and polymorphisms in AGTR1, TFAP2B and TRAF1 in the Japanese population.The subjects consisted of 107 preterm infants with gestational age32 weeks. Extremely low-birthweight infants were treated with prophylactic indomethacin during the first 24 h after birth. Five SNP, namely, rs5186 in AGTR1, rs987237 and rs6930924 in TFAP2B, and rs1056567 and rs10985070 in TRAF1, were genotyped using TaqMan SNP genotyping assays.There were no significant differences in the distributions of the genotypes and allele frequencies of all studied SNP between the PDA group (n = 46) and the non-PDA group (n = 61).There were no significant associations between the studied SNP and the incidence of PDA in Japanese preterm infants. These SNP may not be clinically important predisposing factors for PDA in Japanese preterm infants.

Objectives To ascertain a molecular genetic diagnosis for subjects with neonatal/infantile intrahepatic cholestasis (NIIC) by the use of next-generation sequencing (NGS) and to perform a genotype-phenotype correlation. Study design We recruited Japanese subjects with NIIC who had no definitive molecular genetic diagnosis. We developed a diagnostic custom panel of 18 genes, and the amplicon library was sequenced via NGS. We then compared clinical data between the molecular genetically confirmed subjects with NIIC. Results We analyzed 109 patients with NIIC (“genetic cholestasis,” 31 subjects; “unknown with complications” such as prematurity, 46 subjects; “unknown without complications,” 32 subjects), and a molecular genetic diagnosis was made for 28 subjects (26%). The rate of positive molecular genetic diagnosis in each category was 22 of 31 (71%) for the “genetic cholestasis” group, 2 of 46 (4.3%) for the “unknown with complications” group, and 4 of 32 (12.5%) for the “unknown without complications” group. The grouping of the molecular diagnoses in the group with genetic cholestasis was as follows: 12 with Alagille syndrome, 5 with neonatal Dubin-Johnson syndrome, 5 with neonatal intrahepatic cholestasis caused by citrin deficiency, and 6 with progressive familial intrahepatic cholestasis or benign recurrent intrahepatic cholestasis with low gamma-glutamyl transpeptidase levels. Several clinical datasets, including age of onset, direct bilirubin, and aminotransferases, were significantly different between the disorders confirmed using molecular genetic diagnosis. Conclusion Targeted NGS can be used for molecular genetic diagnosis in subjects with NIIC. Clinical diagnosis should be accordingly redefined in the view of molecular genetic findings.

Not only in newborns with Down syndrome, but newborns without phenotypic features of Down syndrome also develop transient myeloproliferative disorder (TMD). In these cases, trisomy 21 and related chromosomal abnormalities are either constitutionally mosaic or limited to blood cells. Risk factors for early death of these patients are unknown so far. We here report a fatal case of TMD without phenotypic features of Down syndrome and review literature to identify risk factors associated with early death. Not only are gestational age and white blood cell count risk factors for early death in TMD with Down syndrome, but they also appear to be risk factors in TMD without Down syndrome.

Background: Increased survival rates for extremely low birth weight infants have been reported. However, survival rates and prognoses of extremely preterm infants, such as infants born at 22 weeks of gestation, are still poor. Objective: To investigate such infants’ long-term outcomes, developmental assessments were performed. Methods: Seven infants with gestational age of 22 weeks were delivered in our hospital from 2005 to 2008. One infant was a stillbirth despite resuscitation in the delivery room. Six infants, 4 boys and 2 girls, with a gestational age of 22 weeks (range 223/7–226/7 weeks), were admitted to the neonatal intensive care unit (NICU). Birth weights ranged from 514 to 710 g. None of the infants suffered from sepsis, necrotizing enterocolitis, or severe intraventricular hemorrhage. Results:The survival rate was 85.7% (6/7) as a percentage of deliveries and 100% (6/6) as a percentage of NICU admissions. None of the infants suffered from deafness, blindness, cerebral palsy, or epilepsy. Six infants were available for developmental assessments at 18 months’ corrected age. Three infants showed normal developmental quotients, and 3 infants showed developmental delay. Conclusion: In our study, all infants admitted to the NICU at a gestational age of 22 weeks were discharged from the hospital alive. This might suggest that infants after 22 weeks’ gestation be considered eligible for active treatment in Japan, though considering the size of the material, generalizibility of the results cannot be considered guaranteed.