A female case of L1 syndrome that may have developed due to skewed X inactivation.

BACKGROUND: Heterozygous L1CAM variants cause L1 syndrome with hydrocephalus and aplasia/hypoplasia of the corpus callosum. L1 syndrome usually has an X-linked recessive inheritance pattern; however, we report a rare case occurring in a female child. CASE PRESENTATION: The patient's family history was unremarkable. Fetal ultrasonography revealed enlarged bilateral ventricles of the brain and hypoplasia of the corpus callosum. The patient was born at 38 weeks and 4 days of gestation. Brain MRI performed on the 8th day of life revealed enlargement of the brain ventricles, marked in the lateral and third ventricles with irregular margins, and hypoplasia of the corpus callosum. Exome sequencing at the age of 2 years and 3 months revealed a de novo heterozygous L1CAM variant (NM_000425.5: c.2934_2935delp. (His978Glnfs * 25). X-chromosome inactivation using the human androgen receptor assay revealed that the pattern of X-chromosome inactivation in the patients was highly skewed (96.6 %). The patient is now 4 years and 11 months old and has a mild developmental delay (developmental quotient, 56) without significant progression of hydrocephalus. CONCLUSION: In this case, we hypothesized that the dominant expression of the variant allele arising from skewed X inactivation likely caused L1 syndrome. Symptomatic female carriers may challenge the current policies of prenatal and preimplantation diagnoses.

Association between early-term birth and hypoglycaemia in large-for-gestational-age neonates:A retrospective cohort study.

BACKGROUND: The effect of early-term birth on the development of hypoglycaemia in large-for-gestational-age (LGA) neonates is yet to be clarified. This study aimed to clarify the association between hypoglycaemia and early-term birth in LGA neonates. METHODS: This single-centre retrospective cohort study evaluated LGA neonates born at term at Tsurugi Municipal Handa Hospital, Japan. Blood glucose levels were measured immediately and at 1, 2, and 4 hours after birth. The association between early-term birth and hypoglycaemia was evaluated using logistic regression analysis. The prevalence of severe hypoglycaemia and hypoglycaemia according to its timing of development was analysed using Fisher's exact test. RESULTS: In total, 295 neonates were included. Among them, 113 neonates (38.3%) were born at early term and 91 infants (30.8%) had hypoglycaemia. Logistic regression analysis showed a significant association between early-term birth and hypoglycaemia (adjusted odds ratio [95% confidence interval]:2.691 [1.597 to 4.535]). However, there was no significant between-group difference among those with severe hypoglycaemia. CONCLUSIONS: Among LGA neonates, early-term birth is positively associated with neonatal hypoglycaemia. This indicates that among LGA neonates, those born at early term require more careful observation for hypoglycaemia than do those born at later term. J. Med. Invest. 70 : 476-482, August, 2023.

A surge in respiratory syncytial virus infection-related hospitalizations associated with the COVID-19 pandemic: An observational study at pediatric emergency referral hospitals in Tokushima Prefecture.

The outbreak of coronavirus disease (COVID-19) resulted in implementation of social distancing and other public health measures to control the spread of infection and improve prevention, resulting in a decrease in respiratory syncytial virus (RSV) and pediatric respiratory tract infection rates. However, there was a rapid and large re-emergence of RSV infection in Japan. Notably, we were faced with a difficult situation wherein there was a shortage of hospital beds. This study aimed to examine the epidemiological patterns of RSV-related hospitalizations among children before and after the COVID-19 pandemic onset at two pediatric emergency referral hospitals covering the entire Tokushima Prefecture. Data were extracted from electronic medical records of children hospitalized with RSV infection between January 1, 2018, and December 31, 2021. All patients meeting the eligibility criteria were included in this study. The rates of study outcomes were documented annually during 2018-2021 and compared between the 2018-2020 and 2021 periods. In 2020, there was no RSV infection outbreak. Hospitalizations at the peak week in 2021 were 2.2- and 2.8-fold higher than those in 2018 and 2019, respectively. Hospitalizations in 2021 were concentrated within a short period. In addition, there was a significant increase in hospitalizations among children aged 3-5 months and those older than 24 months. The high-flow nasal cannula (HFNC) use rate nearly doubled in 2021. A new pandemic in the future may cause an outbreak of RSV infection that can result in an intensive increase in the number of hospitalizations of pediatric patients requiring respiratory support, especially in infants aged <6 months. There is an urgent need to improve the preparedness of medical systems, particularly in terms of the number of inpatient beds and the immediate availability of HFNC.

Osteoarticular infections at a pediatric emergency core hospital in Japan.

OBJECTIVES: Osteomyelitis (OM) and septic arthritis (SA) in childhood might cause complications, sequelae, or even death if diagnosis and treatment are delayed. Here, we examined the outcomes of OM/SA at a pediatric emergency core hospital in Japan. METHODS: This was a single-center, retrospective, observational cohort study at a pediatric emergency core hospital in Japan. Pediatric outpatients who underwent magnetic resonance imaging at the hospital in the period 2012?2020 were recruited. Primary outcomes were sequelae, recurrent symptoms, chronicity, and death. RESULTS: Fifteen OM/SA patients (9 OM, 4 SA, 2 OM+SA) were recruited. The identified major pathogens included methicillin-susceptible Staphylococcus aureus (40.0 %, n=6) and methicillin-resistant S. aureus (13.3 %, n=2). Mean time from onset to first hospital visit, hospitalization, and initiation of effective antibiotics was 2 days, 3.9?±?1.8 days, and 4.9±2.2 days, respectively. All OM/SA patients recovered without complications or sequelae. CONCLUSIONS: In this study, all patients with OM/SA showed a good prognosis. Despite the small sample size, this pilot study suggests that the pediatric emergency core system in Japan provides early treatment and a good prognosis for patients diagnosed with OM/SA. J. Med. Invest. 70 : 236-240, February, 2023.

A pediatric case of infliximab-resistant ulcerative colitis successfully treated using vedolizumab.

Pediatric ulcerative colitis is likely to be more severe than adult ulcerative colitis. Failure to thrive should be considered during therapy. A 10-year-old boy was diagnosed with ulcerative colitis based on his clinical presentation and colonoscopy and biopsy results. The administration of 5-aminosalicylic acid and prednisolone resulted in remission ; however, the symptoms reappeared after the discontinuation of prednisolone. Then, infliximab was administered ; however, the patient was resistant to it and appeared to be dependent on prednisolone. Vedolizumab, a monoclonal antibody against ?4?7 integrin, was administered, which resulted in rapid remission. A steady decrease in prednisolone followed, and remission was maintained even after prednisolone discontinuation. Vedolizumab may be effective in pediatric patients with moderate-to-severe refractory ulcerative colitis. Vedolizumab prevents lymphocytes from binding to MAdCAM-1, which is selectively expressed in the gastrointestinal submucosa, leading to the mitigation of the systemic side effects of immunosuppression, such as infections. In Japan, vedolizumab use is not yet approved for use in children, but its effectiveness and safety in children is expected to be investigated in the future. J. Med. Invest. 70 : 294-297, February, 2023.

A case of epilepsy with myoclonic atonic seizures caused by SLC6A1 gene mutation due to balanced chromosomal translocation.

INTRODUCTION: Epilepsy with myoclonic atonic seizures (EMAtS) was previously thought to occur in normally developing children. We report a female case of EMAtS and mild developmental delay before onset. Importantly, a de novo balanced chromosomal translocation was recognized in the patient. CASE PRESENTATION: The patient was a 4-year-old girl. Mild developmental delay was observed during infancy. At the age of one and a half years, she developed atonic seizures once a month. At 4 years of age, her seizures increased to more than 10 times per hour. An ictal electroencephalogram (EEG) showed a 3-4-Hz spike-and-wave complex, which was consistent with atonic and myoclonic seizures of the trunk, eyelids, and lips. Therefore, EMAtS was diagnosed based on the symptoms and EEG findings. After administration of valproic acid (VPA), the epileptic seizures disappeared immediately. At the age of 5 years and 2 months, the seizures recurred but disappeared again when the dose of VPA was increased. Subsequently, no recurrence was observed until 6 years and 3 months of age on VPA and lamotrigine. Chromosome analysis of the patient disclosed 46,XX,t(3;11)(p25;q13.1)dn. Long-read sequencing of the the patient's genomic DNA revealed that the 3p25.3 translocation breakpoint disrupted the intron 7 of the SLC6A1 gene. CONCLUSION: The SLC6A1 disruption by chromosome translocation well explains the clinical features of this patient. Long-read sequencing is a powerful technique to determine genomic abnormality at the nucleotide level for disease-associated chromosomal abnormality.

Patient attendance at a pediatric emergency referral hospital in an area with low COVID-19 incidence.

The purpose of this study was to clarify the effects of individual infection control measures and physical distancing on pediatric medical care in a local prefecture in Japan, where the incidence of coronavirus disease (COVID-19) in pediatric patients was extremely low. We extracted data from hospital records on the number of outpatients, inpatients, infectious disease consultations, and consultations for representative pediatric diseases. We compared attendance in 2017-2019, before the COVID-19 pandemic, with 2020, when COVID-19 spread to Japan. There were no COVID-19 patients in the pediatric department during the study period. The total number outpatient visits decreased by 24.4%, and the number of hospital admissions, excluding neonatal care unit admissions, decreased by approximately 35%. There was a marked reduction in the number of hospitalizations for infectious diseases such as influenza (-74.8%) and respiratory syncytial virus infection (-93.5%), and the number of hospitalizations for bronchitis/pneumonia, Kawasaki disease, and bronchial asthma decreased. In contrast, the number of clinical psychological interventions and cases reported to the child guidance center increased. In the context of pandemic infectious diseases, it is important to control the spread of problematic infectious diseases by individual infection control measures and physical distancing. However, it is necessary to maintain social life as much as possible for the mental health and physical development of children.

Escherichia coli pyomyositis in a patient with Down syndrome: A case report.

Pyomyositis is an infection of the skeletal muscle that involves intramuscular abscess formation. It is typically caused by gram-positive bacteria, especially Staphylococcus aureus. Few cases of Escherichia coli pyomyositis have been reported in immunocompromised adult patients, while none have been reported in children. We present a case of a 4-year-old boy with Down syndrome who developed Escherichia coli pyomyositis. The patient presented to our hospital with a fever and right forearm swelling. The magnetic resonance imaging findings suggested pyomyositis of the right forearm muscle and osteomyelitis of the distal radius. Both the blood and puncture fluid cultures were negative. Cefazolin and vancomycin were administered, and his blood examination results and right forearm swelling improved; however, a slight fever persisted. The multiplex polymerase chain reaction isolated the chuA gene but not the YjaA gene; thus the patient was diagnosed with pyomyositis and osteomyelitis caused by Escherichia coli group D. The cefazolin was substituted with meropenem, and the vancomycin was discontinued. Thereafter, his fever promptly improved, which indicated that the cause of persistent fever was vancomycin drug fever. The patient was discharged after receiving 3 weeks of intravenous antimicrobial therapy, and recovered fully with no long-term sequelae. To the best of our knowledge, this is the first reported case of Escherichia coli pyomyositis in a child. The findings in this case suggest that Escherichia coli should be considered when choosing initial empiric therapy for pyomyositis, especially in children with underlying conditions.

Improvement of epilepsy with lacosamide in a patient with ring chromosome 20 syndrome.

BACKGROUND: Ring chromosome 20 syndrome is a rare chromosomal disorder characterized by refractory seizure, mental retardation, and behavioral problems. Although there are reports of the effective treatment of patients with antiepileptic drugs (AEDs), no study has reported the effects of lacosamide(LCM) in children with this syndrome. We report a 7-year-old boy with this syndrome whose refractory and behavioral abnormalities have been remarkably improved by treatment with LCM. CASE PRESENTATION: The patient was a 7-year-old boy with no medical or family history of epilepsy. He developed epilepsy with cessation of movement and derivation of the eyes followed by hyperkinetic seizures that made him squeak strangely and cling to his parents. The seizures lasted for less than a minute and were frequent (they occurred more than 30 times a day), particularly at night. Behavioral abnormalities such as hyperactivity also presented. Brain magnetic resonance imaging revealed no structural abnormalities, but an interictal electroencephalogram (EEG) indicated spikes and waves in the frontal lobe dominantly, and ictal single-photon emission computed tomography (SPECT) revealed a blood flow increase in the bilateral orbital frontal area in comparison to interictal SPECT. After chromosome examination, we diagnosed the patient with ring chromosome 20 syndrome (4/30 mosaic). Carbamazepine was ineffective, and seizures were exacerbated with levetiracetam (LEV). LCM was added to the treatment regimen with valproic acid (VPA) and lamotrigine (LTG); consequently, the seizures disappeared, and EEG results also improved. The patient's behavioral disorders, such as hyperactivity, were improved, and he was able to return to elementary school. CONCLUSION: Although VPA and LTG are generally effective for the treatment of ring chromosome 20 syndrome, they do not completely suppress seizures. LCM can be considered an effective option for seizure control in patients with this syndrome.

Glomerular angiotensin-converting enzyme 2 in pediatric IgA nephropathy.

BACKGROUND: Angiotensin-converting enzyme (ACE) 2 is a homolog of ACE and is thought to be a potent counter-regulator against ACE activity. However, the role of ACE2 has not been investigated in pediatric patients with IgA nephropathy (IgAN). This study was performed to examine the relationship between ACE2 expression and the development of pediatric IgAN. METHODS: We performed immunohistochemical analysis of ACE2 and ACE in 39 patients with pediatric IgAN and 14 patients with minor glomerular abnormalities, and elucidated the effects of various cytokines on ACE2 expression in cultured human mesangial cells. RESULTS: ACE2 expression levels in glomeruli and tubules were positively correlated with the mesangial hypercellularity score, while ACE expression levels in glomeruli and tubules are not. Multiple regression analysis showed that the mesangial hypercellularity score correlated with the ACE2 expression level in glomeruli and the urinary protein-creatinine ratio. In IgAN patients not treated with a renin-angiotensin system blocker, ACE2 expression levels in glomeruli were significantly increased compared to patients with minor glomerular abnormalities. IgAN patients treated with a renin-angiotensin system blocker did not show this increase in ACE2 expression. Furthermore, cultured human MC showed increased ACE2 mRNA and protein after treatment with IL-1ß, a pro-inflammatory cytokine in IgAN. In fact, glomerular expressions of IL-1ß were remarkably increased in patients with IgAN. CONCLUSION: These data indicate that ACE2 expression in glomeruli is associated with mesangial hypercellularity in early lesions of pediatric IgAN.

Novel concept microarray enabling PCR and multistep reactions through pipette-free aperture-to-aperture parallel transfer.

BACKGROUND: The microarray has contributed to developing the omic analysis. However, as it depends basically on the surface reaction, it is hard to perform bulk reactions and sequential multistep reactions. On the other hand, the popular microplate technology, which has a great merit of being able to perform parallel multistep reactions, has come to its limit in increasing the number of wells (currently, up to 9600) and reducing the volume to deal with due to the difficulty in operations. RESULTS: Here, we report a novel microarray technology which enables us to explore advanced applications, termed microarray-with-manageable volumes (MMV). The technical essence is in the pipette-free direct parallel transfer from well to well performed by centrifugation, evading the evaporation and adsorption-losses during handling. By developing the MMV plate, accompanying devices and techniques, generation of multiple conditions (256 kinds) and performance of parallel multistep reactions, including PCR and in vitro translation reactions, have been made possible. These were demonstrated by applying the MMV technology to searching lysozyme-crystallizing conditions and selecting peptides aimed for Aß-binding or cathepsin E-inhibition. CONCLUSIONS: With the introduction of a novel concept microarray (MMV) technology, parallel and multistep reactions in sub-µL scale have become possible.

Development of systemic in vitro evolution and its application to generation of peptide-aptamer-based inhibitors of cathepsin E.

Proteases are involved in various biological functions. Thus, inhibition of their activities is scientifically interesting and medically important. However, there is no systematic method established to date to generate endopeptidase inhibitory peptides. Here, we report a general system to identify endopeptidase inhibitory peptides based on the use of in vitro evolution. Using this system, we generated peptides that inhibit cathepsin E (CE) specifically at a submicromolar IC(50). This system generates protease inhibitor peptides utilizing techniques of cDNA display, selection-by-function, Y-ligation-based block shuffling, and others. We further demonstrated the importance and effectiveness of a secondary library for obtaining small-sized and active peptides. CE inhibitory peptides generated by this method were characterized by a small size (8 to 12 aa) and quite different sequences, suggesting that they bind to different sites on CE. Typical CE inhibitory peptide aptamers obtained here (P(i)101; SCGG IIII SCIA) have half an inhibition activity (K(i); 5 nM) of pepstatin A (potent CE inhibitor) without inhibiting cathepsin D (structurally similar to CE). The general applicability of this system suggests that it may be useful to identify inhibitory peptides for various kinds of proteases and that it may therefore contribute to protein science and drug discovery. The peptide binding to a protein is discussed in comparison with the antibody binding to an antigen.