Biallelic COLGALT1 variants are associated with cerebral small vessel disease.

OBJECTIVE: Approximately 5% of cerebral small vessel diseases are hereditary, which include COL4A1/COL4A2-related disorders. COL4A1/COL4A2 encode type IV collagen α1/2 chains in the basement membranes of cerebral vessels. COL4A1/COL4A2 mutations impair the secretion of collagen to the extracellular matrix, thereby resulting in vessel fragility. The diagnostic yield for COL4A1/COL4A2 variants is around 20 to 30%, suggesting other mutated genes might be associated with this disease. This study aimed to identify novel genes that cause COL4A1/COL4A2-related disorders. METHODS: Whole exome sequencing was performed in 2 families with suspected COL4A1/COL4A2-related disorders. We validated the role of COLGALT1 variants by constructing a 3-dimensional structural model, evaluating collagen ß (1-O) galactosyltransferase 1 (ColGalT1) protein expression and ColGalT activity by Western blotting and collagen galactosyltransferase assays, and performing in vitro RNA interference and rescue experiments. RESULTS: Exome sequencing demonstrated biallelic variants in COLGALT1 encoding ColGalT1, which was involved in the post-translational modification of type IV collagen in 2 unrelated patients: c.452 T > G (p.Leu151Arg) and c.1096delG (p.Glu366Argfs*15) in Patient 1, and c.460G > C (p.Ala154Pro) and c.1129G > C (p.Gly377Arg) in Patient 2. Three-dimensional model analysis suggested that p.Leu151Arg and p.Ala154Pro destabilized protein folding, which impaired enzymatic activity. ColGalT1 protein expression and ColGalT activity in Patient 1 were undetectable. RNA interference studies demonstrated that reduced ColGalT1 altered COL4A1 secretion, and rescue experiments showed that mutant COLGALT1 insufficiently restored COL4A1 production in cells compared with wild type. INTERPRETATION: Biallelic COLGALT1 variants cause cerebral small vessel abnormalities through a common molecular pathogenesis with COL4A1/COL4A2-related disorders. Ann Neurol 2018;84:843-853.

Asymptomatic C-reactive protein elevation in neutropenic children.

BACKGROUND: Febrile neutropenia (FN) can be a life-threatening complication in children with malignancies. There is no standardized preventive treatment for childhood FN, and information on C-reactive protein (CRP) elevation in afebrile patients with neutropenia (CEAN) is limited. The aim of this study was therefore to identify the association between CEAN and FN onset, and evaluate the efficacy of broad-spectrum antibiotics for FN prophylaxis. METHODS: We retrospectively reviewed the medical records of 22 consecutive pediatric patients with hematologic malignancies (acute myeloid leukemia, n = 2; acute lymphoid leukemia, n = 20) admitted to the present institution between 2006 and 2011. CEAN was defined as CRP elevation ≥0.05 mg/dL between the two most recent blood tests with no fever. We identified CEAN before FN onset, and assessed the efficacy of broad-spectrum antibiotics for FN prevention in CEAN. FN incidence within 48 h after CEAN detection was compared between prophylactic and non-prophylactic episodes. RESULTS: CEAN was observed before FN onset in 20 (55.6%), of 36 FN episodes. Among the 95 analyzed CEAN episodes, broad-spectrum antibiotics had been used for 30 episodes (prophylactic episodes), whereas these antibiotics had not been used in 60 episodes (non-prophylactic episodes). Prophylactic episodes had a significantly lower FN incidence than non-prophylactic episodes (6.7% and 31%, respectively, P < 0.01) within 48 h after CEAN detection. Bacteremia was observed in three non-prophylactic episodes. CONCLUSION: Patients with CEAN are at higher risk of FN, and physicians may consider the use of broad-spectrum antibiotics to prevent FN development.

A case report of mitochondrial respiratory chain disorder in the neonatal period for which home mechanical ventilation was introduced.

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.

Single nucleotide polymorphisms in AGTR1, TFAP2B, and TRAF1 are not associated with the incidence of patent ductus arteriosus in Japanese preterm infants.

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 <32 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. RESULTS: 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). CONCLUSIONS: 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.

Phenotypic spectrum of COL4A1 mutations: porencephaly to schizencephaly.

OBJECTIVE: Recently, COL4A1 mutations have been reported in porencephaly and other cerebral vascular diseases, often associated with ocular, renal, and muscular features. In this study, we aimed to clarify the phenotypic spectrum and incidence of COL4A1 mutations. METHODS: We screened for COL4A1 mutations in 61 patients with porencephaly and 10 patients with schizencephaly, which may be similarly caused by disturbed vascular supply leading to cerebral degeneration, but can be distinguished depending on time of insult. RESULTS: COL4A1 mutations were identified in 15 patients (21%, 10 mutations in porencephaly and 5 mutations in schizencephaly), who showed a variety of associated findings, including intracranial calcification, focal cortical dysplasia, pontocerebellar atrophy, ocular abnormalities, myopathy, elevated serum creatine kinase levels, and hemolytic anemia. Mutations include 10 missense, a nonsense, a frameshift, and 3 splice site mutations. Five mutations were confirmed as de novo events. One mutation was cosegregated with familial porencephaly, and 2 mutations were inherited from asymptomatic parents. Aberrant splicing was demonstrated by reverse transcriptase polymerase chain reaction analyses in 2 patients with splice site mutations. INTERPRETATION: Our study first confirmed that COL4A1 mutations are associated with schizencephaly and hemolytic anemia. Based on the finding that COL4A1 mutations were frequent in patients with porencephaly and schizencephaly, genetic testing for COL4A1 should be considered for children with these conditions.

Risk factors for early death in transient myeloproliferative disorder without phenotypic features of Down syndrome: a case report and literature review.

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.

Effects of exchange transfusion on cytokine profiles in necrotizing enterocolitis.

To study the effect of exchange transfusion on cytokine profiles in a patient with necrotizing enterocolitis, the levels of 12 cytokines and serum calprotectin were measured among exchange transfusion. A male extremely low birth weight infant was in non-compensated shock and diagnosed stage 3 necrotizing enterocolitis. Exchange transfusion was performed for critical condition, refractory hypotension and disseminated intravascular coagulation. After exchange transfusion, the patient's blood pressure increased and stabilized. Then an enterostomy was performed and revealed necrosis of the ascending colon. Of the cytokines examined, interleukin-8 and serum calprotectin were high before exchange transfusion and decreased after exchange transfusion.

Frameshift mutations of the ARX gene in familial Ohtahara syndrome.

PURPOSE: Ohtahara syndrome is one of the most severe and earliest forms of epilepsy and is frequently associated with brain malformations, such as hemimegalencephaly. Recently, longer expansion of the first polyalanine tract of ARX was found to be causative for Ohtahara syndrome without brain malformation, whereas premature termination mutations of ARX were found to cause severe brain malformations, such as lissencephaly or hydranencephaly. Both are designated as ARX-related interneuronopathies. METHODS: We investigated the molecular basis of Ohtahara syndrome in two families, comprising six male patients in two generations demonstrating X-linked inheritance. RESULTS: Novel frameshift mutations in the terminal exon of the ARX gene (Ala524fsX534 and E536fsX672) were identified in two patients (2 and 13 years, each) from both families. Two patients developed West syndrome, and one of these later developed Lennox-Gastaut syndrome. Brain magnetic resonance imaging (MRI) of all patients showed no brain malformations in contrast to the patients with a premature termination mutation in other exons of ARX. DISCUSSION: The etiology of Ohtahara syndrome is heterogeneous; however, the molecular analysis of ARX should be considered in sporadic or familial male patients with Ohtahara syndrome.

Cytokine profiles before and after exchange transfusion in a neonate with transient myeloproliferative disorder and hepatic fibrosis.

SUMMARY: To study the effect of exchange transfusion on cytokine profiles in a patient with transient myeloproliferative disorder and hepatic fibrosis in which cytokines were measured before and after exchange transfusion. A newborn female was diagnosed with Down syndrome phenotypically and on karyotyping. Laboratory data showed a high leukocyte count with blast cells in the peripheral blood and liver dysfunction. Exchange transfusion was performed on day 1. However, respiratory distress and multiorgan failure progressed, and she died after 16 days. Of the cytokines examined, transforming growth factor-beta1 and interleukin-7 were extremely high before exchange transfusion, and decreased after exchange transfusion.

Echovirus Type 7 Virus-Associated Hemophagocytic Syndrome in a Neonate Successfully Treated With Intravenous Immunoglobulin Therapy: A Case Report.

Virus-associated hemophagocytic syndrome (VAHS) in the neonatal period has a high mortality. Although clear diagnostic criteria and treatment methods have not been established, early diagnosis and treatment are critical. However, treatments for VAHS have potentially serious side effects, especially during the neonatal period. Echovirus type 7 can cause maternal infection around parturition and be vertically transmitted to the neonate and induce VAHS. Intravenous immunoglobulin (IVIG) therapy could be a first-line therapy for neonatal VAHS, so that treatments with potentially serious side effects, including cyclosporine A and etoposide, could be avoided. A case of VAHS associated with echovirus type 7 that was successfully treated with IVIG therapy is reported.

Late-onset circulatory dysfunction of premature infants and late-onset periventricular leukomalacia.

BACKGROUND: The sudden appearance of hypotension and oliguria without obvious cause following stable circulation and respiration in preterm infants is frequent in Japan. Such episodes are referred to as late-onset circulatory dysfunction of premature infants (LCD). Volume expanders and inotropic agents are often ineffective against this condition, whereas i.v. steroids are significantly effective. A major problem is that cystic periventricular leukomalacia (PVL) often develops a few weeks after an episode. The aim of the present study was to clarify the risk factors, including LCD, related to cystic PVL. METHODS: A case-control study was performed for preterm infants who were delivered at <33 weeks of gestation and admitted to seven neonatal intensive care units in Japan. Cystic PVL infants were stratified into early-onset PVL diagnosed within 28 days of age and late-onset PVL diagnosed after more than 28 days of age. The reported and new risk factors for PVL, for each group of PVL infants, and for all PVL infants, were compared with controls. RESULTS: Thirty-two infants were diagnosed with cystic PVL (17 early-onset and 15 late-onset). All PVL infants significantly differed from controls on Apgar score, number of abortions and pregnancies, intraventricular hemorrhage, and LCD. LCD was diagnosed in 28.1% of both PVL groups compared with 6.3% of controls (P = 0.02). Multivariate analysis demonstrated significant association between late-onset PVL and LCD. CONCLUSION: LCD was significantly associated with cystic PVL, especially late-onset PVL. Elucidating the cause of LCD might reduce the incidence of PVL and improve the neurological prognosis of preterm infants.

Neurodevelopmental outcomes at 3 years old for infants with birth weights under 500 g.

BACKGROUND: 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 (<3 SD) at 3 years old. CONCLUSION: Although the survival rate among live births was good (80%) in this study, neurodevelopmental outcomes remained poor in infants with birth weights ≤500 g. Further large studies are needed to assess long-term outcomes for extremely small infants.

A case of pediatric multiple sclerosis presenting with a tumefactive demyelinating lesion.

Pediatric multiple sclerosis accompanied by a tumefactive demyelinating lesion (TDL) is extremely rare. Because it is very difficult to distinguish TDLs from neoplasms, invasive brain biopsies are required for a definitive diagnosis. MR spectroscopy (MRS) without brain biopsy was recently shown diagnostic in some patients with TDLs, based on the elevation of glutamate/glutamine peaks. This report describes the clinical course of a 9-year-old girl with multiple sclerosis following a TDL and discusses the usefulness of MRS and brain biopsies to diagnose TDLs.

Hypoxic ischemic encephalopathy in a case of intranuclear rod myopathy without any prenatal sentinel event.

Intranuclear rod myopathy (IRM), a variant of nemaline myopathy, is characterized by the presence of nemaline bodies in myonuclei. We report a case of IRM presenting with hypoxic ischemic encephalopathy (HIE). There were no prenatal complications caused by fetal brain injury. Although no nemaline bodies were observed in the cytoplasm, intranuclear rods were observed in some fibers under light and electron microscopy. Molecular analysis identified a heterozygous variant, c.449C>T (p.Thr150Ile), in ACTA1. On magnetic resonance imaging at 9days of age, injuries to the basal ganglia, thalamus, and brainstem consistent with perinatal HIE were seen. Respiratory insufficiency at birth was strongly suspected to be the cause of HIE. Our case highlights that a patient with a congenital neuromuscular disorder who presents with severe respiratory dysfunction requiring substantial resuscitative efforts at birth can be complicated by HIE without any prenatal sentinel event. Prenatal detection of neuromuscular disorders, careful management of delivery, and neonatal resuscitation and adequate respiratory management are important in preventing irreversible brain injury in these patients.

Nemaline myopathy with KLHL40 mutation presenting as congenital totally locked-in state.

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.