RMRP-related short stature: A report of six additional Japanese individuals with cartilage hair hypoplasia and literature review.

Biallelic pathogenic variants in RMRP, the gene encoding the RNA component of RNase mitochondrial RNA processing enzyme complex, have been reported in individuals with cartilage hair hypoplasia (CHH). CHH is prevalent in Finnish and Amish populations due to a founder pathogenic variant, n.71A > G. Based on the manifestations in the Finnish and Amish individuals, the hallmarks of CHH are prenatal-onset growth failure, metaphyseal dysplasia, hair hypoplasia, immunodeficiency, and other extraskeletal manifestations. Herein, we report six Japanese individuals with CHH from four families. All probands presented with moderate short stature with mild metaphyseal dysplasia or brachydactyly. One of them had hair hypoplasia and the other immunodeficiency. By contrast, the affected siblings of two families showed only mild short stature. We also reviewed all previously reported 13 Japanese individuals. No n.71A > G allele was detected. The proportions of Japanese versus Finnish individuals were 0% versus 70% for birth length < -2.0 SD, 84% versus 100% for metaphyseal dysplasia and 26% versus 88% for hair hypoplasia. Milder manifestations in the Japanese individuals may be related to the difference of genotypes. The mildest form of CHH phenotypes is mild short stature without overt skeletal alteration or extraskeletal manifestation and can be termed "RMRP-related short stature".

Phenotypic Variation in 46,XX Disorders of Sex Development due to the Fourth Zinc Finger Domain Variant of WT1: A Familial Case Report.

INTRODUCTION: The variants in the zinc finger (ZF) domains 1-3 in WT1 are one of the major causes of 46,XY disorders of sex development (DSD). Recently, variants in the fourth ZF (ZF4 variants) were reported to cause 46,XX DSD. However, all the 9 patients reported were de novo, and no familial cases were identified. CASE PRESENTATION AND RESULTS: The proband (16-year-old social female) had a 46,XX karyotype with dysplastic testes and moderate virilization in genitalia. A ZF4 variant, p.Arg495Gln, in WT1 was identified in the proband, her brother, and mother. The mother did not show any virilization with normal fertility, and the 46,XY brother developed normal puberty. CONCLUSION: The phenotypic variations due to the ZF4 variant are extremely broad in 46,XX cases.

International Consensus Guideline on Small for Gestational Age: Etiology and Management From Infancy to Early Adulthood.

This International Consensus Guideline was developed by experts in the field of small for gestational age (SGA) of 10 pediatric endocrine societies worldwide. A consensus meeting was held and 1300 articles formed the basis for discussions. All experts voted about the strengths of the recommendations. The guideline gives new and clinically relevant insights into the etiology of short stature after SGA birth, including novel knowledge about (epi)genetic causes. Further, it presents long-term consequences of SGA birth and also reviews new treatment options, including treatment with gonadotropin-releasing hormone agonist (GnRHa) in addition to growth hormone (GH) treatment, as well as the metabolic and cardiovascular health of young adults born SGA after cessation of childhood GH treatment in comparison with appropriate control groups. To diagnose SGA, accurate anthropometry and use of national growth charts are recommended. Follow-up in early life is warranted and neurodevelopment evaluation in those at risk. Excessive postnatal weight gain should be avoided, as this is associated with an unfavorable cardiometabolic health profile in adulthood. Children born SGA with persistent short stature < -2.5 SDS at age 2 years or < -2 SDS at 3 to 4 years of age, should be referred for diagnostic workup. In case of dysmorphic features, major malformations, microcephaly, developmental delay, intellectual disability, and/or signs of skeletal dysplasia, genetic testing should be considered. Treatment with 0.033 to 0.067 mg GH/kg/day is recommended in case of persistent short stature at age of 3 to 4 years. Adding GnRHa treatment could be considered when short adult height is expected at pubertal onset. All young adults born SGA require counseling to adopt a healthy lifestyle.

Atrophic autoimmune thyroiditis complicated with systemic lupus erythematosus.

Atrophic autoimmune thyroiditis (AAT) is a type of autoimmune thyroiditis that causes hypothyroidism without thyroid enlargement. AAT is distinguished from Hashimoto's disease (HD) by the absence of thyroid enlargement. AAT is rare in children and clinically characterised by severe primary hypothyroidism. Autoimmune thyroiditis, especially HD, is commonly complicated with systemic lupus erythematosus (SLE). Here, we reported the patient with AAT as the initial presentation of SLE complicated with generalised myxoedema, whose presentation was a diagnostic challenge. This patient illustrates the importance of the early recognition of an atypical presentation of SLE patients with autoimmune thyroiditis. It is possible that similar cases have existed in the past but have been overlooked as HD. A large-scale study is necessary to clarify the reality of AAT in SLE.

Transient immune deficiency accompanied with homozygous CBL rare variant.

BACKGROUND: A critical role in cellular proliferation is played by Casitas B-lineage Lymphoma proto-oncogene (CBL). Germline heterozygous CBL variants give rise to CBL syndrome, which is phenotypically similar to RASopathy. Somatic mutations in CBL have been reported in patients with juvenile myelomonocytic leukemia (JMML). METHODS: Exome analysis was performed in a patient with immunodeficiency who developed Pneumocystis jirovecii pneumonia. RESULTS: Exome analysis identified a homozygous CBL missense variant. Cell biological analysis of this CBL variant confirmed attenuated function. CONCLUSION: Spontaneous regression of hematological proliferation has been observed in patients with CBL-mutated JMML and in patients with CBL syndrome. Intriguingly, immunological impairment was spontaneously ameliorated by aging in this patient.

Clinical and Genetic Characterization of Patients with Artemis Deficiency in Japan.

PURPOSE: Artemis is an exonuclease essential for V(D)J recombination and repair of DNA double-stranded breaks. Pathogenic variants in DCLRE1C encoding Artemis cause T-B-NK+ severe combined immunodeficiency (SCID), and patients with Artemis-deficient SCID (ART-SCID) require definitive therapy with allogeneic hematopoietic cell transplantation (HCT). Here we describe the clinical and genetic characteristics of patients with ART-SCID who were diagnosed in Japan from 2003 to 2022. METHODS: Clinical data of ART-SCID patients who were diagnosed between 2003 and 2022 in Japan were collected from their physicians using a questionnaire. RESULTS: ART-SCID diagnosis was made in eight patients from seven families with severe infections within 6 months of life. Two patients had missense variants, five patients had large genomic deletions, and one patient was compound heterozygous for a missense variant and large genomic deletion. All eight underwent allogeneic HCT within 4 months after the diagnosis, 7 receiving a conditioning regimen containing alkylating agents, and one patient without conditioning due to uncontrolled infection. Two patients with poor performance status (PS) died of complications 410 days and 32 days post-HCT, respectively. Of the six surviving patients with a median follow-up time of 8.3 (0.5-17.9) years, three patients had growth retardation. The patients with PS of 0-2 showed a tendency for better overall survival than those with PS 3-4. CONCLUSION: Large deletions were the most common genetic cause of ART-SCID in Japan. To improve HCT outcome, early diagnosis with newborn screening for SCID is urgently needed.

Clinical and molecular findings in three Japanese patients with N-acetylneuraminic acid synthetase-congenital disorder of glycosylation (NANS-CDG).

We report clinical and molecular findings in three Japanese patients with N-acetylneuraminic acid synthetase-congenital disorder of glycosylation (NANS-CDG). Patient 1 exhibited a unique constellation of clinical features including marked hydrocephalus, spondyloepimetaphyseal dysplasia (SEMD), and thrombocytopenia which is comparable to that of an infant reported by Faye-Peterson et al., whereas patients 2 and 3 showed Camera-Genevieve type SMED with intellectual/developmental disability which is currently known as the sole disease name for NANS-CDG. Molecular studies revealed a maternally inherited likely pathogenic c.207del:p.(Arg69Serfs*57) variant and a paternally derived likely pathogenic c.979_981dup:p.(Ile327dup) variant in patient 1, a homozygous likely pathogenic c.979_981dup:p.(Ile327dup) variant caused by maternal segmental isodisomy involving NANS in patient 2, and a paternally inherited pathogenic c.133-12T>A variant leading to aberrant splicing and a maternally inherited likely pathogenic c.607T>C:p.(Tyr203His) variant in patient 3 (reference mRNA: NM_018946.4). The results, together with previously reported data, imply that (1) NANS plays an important role in postnatal growth and fetal brain development; (2) SMED is recognizable at birth and shows remarkable postnatal evolution; (3) NANS-CDG is associated with low-normal serum sialic acid, obviously elevated urine N-acetylmannosamine, and normal N- and O-glycosylation of serum proteins; and (4) NANS-CDG is divided into Camera-Genevieve type and more severe Faye-Peterson type.

Clinical report: Chronic liver dysfunction in an individual with an AMOTL1 variant.

AMOTL1 is a member of the Motin protein family and localizes to tight junctions and is involved in cell polarity and paracellular permeability. Pathological variants have been reported in three patients from two separate families in recent years. The clinical spectrum includes cleft lip and palate along with a high incidence of congenital cardiac disease and ear malformations. We report a case of AMOTL1 pathogenic variant in a 11-year-old male patient with nonspecific and chronic liver dysfunction accompanied by persistently elevated liver enzymes since early infancy. Liver biopsy at 8 years of age revealed a mildly dilated central vein and sinusoid with no specific etiology. Liver dysfunction is not a known clinical feature of AMOTL1 malfunction. However, given that the protein is known to be involved in angiogenesis, it may be inferred that abnormalities in this process may lead to liver dysfunction. This is the first report of liver dysfunction identified in a patient with AMOTL1 malfunction, which will shed light on other putative functions of the protein.

Transcriptome analysis of umbilical cord mesenchymal stem cells revealed fetal programming due to chorioamnionitis.

Although chorioamnionitis (CAM) has been demonstrated to be associated with numerous short- and long-term morbidities, the precise mechanisms remain unclear. One of the reasons for this is the lack of appropriate models for analyzing the relationship between the fetal environment and chorioamnionitis and fetal programming in humans. In this study, we aimed to clarify the fetal programming caused by CAM using the gene expression profiles of UCMSCs. From nine preterm neonates with CAM (n = 4) or without CAM (n = 5), we established UCMSCs. The gene expression profiles obtained by RNA-seq analysis revealed distinctive changes in the CAM group USMSCs. The UCMSCs in the CAM group had a myofibroblast-like phenotype with significantly increased expression levels of myofibroblast-related genes, including α-smooth muscle actin (p < 0.05). In the pathway analysis, the genes involved in DNA replication and G1 to S cell cycle control were remarkably decreased, suggesting that cellular proliferation was impaired, as confirmed by the cellular proliferation assay (p < 0.01-0.05). Pathway analysis revealed that genes related to white fat cell differentiation were significantly increased. Our results could explain the long-term outcomes of patients who were exposed to CAM and revealed that UCMSCs could be an in vitro model of fetal programming affected by CAM.

PAX3/7-FOXO1 fusion-negative alveolar rhabdomyosarcoma in Schuurs-Hoeijmakers syndrome.

PAX3/7-FOXO1 fusion-negative alveolar rhabdomyosarcoma (ARMS) developed in a patient presenting with intellectual disability and dysmorphic facial features. Whole exome sequencing analysis of a germline sample identified a PACS1 c.607 C>T de novo variant and the patient was diagnosed with Schuurs-Hoeijmakers syndrome (SHS). SHS is a rare disease characterized by intellectual disability and dysmorphic facial features, among various physical abnormalities, due to PACS1 c.607 C>T de novo variant. Due to the rarity of the SHS, diagnosis based on phenotypic information is difficult. To date, there have been no previous reports describing malignancy associated with SHS. Comprehensive somatic mutation analysis revealed a unique pattern of genetic alterations in the PAX3/7-FOXO1 fusion-negative ARMS tumor, including mutations in the oncogene, HRAS; MYOD1, a molecule essential for muscle differentiation; and KMT2C and TET1, genes encoding factors involved in epigenetic regulation. Although the role of PACS1 in tumorigenesis is unclear, it is reported to function in apoptosis regulation. Our case suggests that PACS1 could have a novel role in oncogenesis.

Endocrinopathies in Inborn Errors of Immunity.

Inborn errors of immunity (IEI), caused by hereditary or genetic defects, are a group of more than 400 disorders, in which the immune system, including lymphocytes, neutrophils, macrophages, and complements, does not function properly. The endocrine system is frequently affected by IEI as an associated clinical feature and a complex network of glands which regulate many important body functions, including growth, reproduction, homeostasis, and energy regulation. Most endocrine disorders associated with IEI are hypofunction which would be treated with supplementation therapy, and early diagnosis and appropriate management are essential for favorable long-term outcomes in patients with IEI. In this review, we aimed to comprehensively summarize and discuss the current understanding on the clinical features and the pathophysiology of endocrine disorders in IEI. This review is composed with three parts. First, we discuss the two major pathophysiology of endocrinopathy in IEI, autoimmune response and direct effects of the responsible genes. Next, the details of each endocrinopathy, such as growth failure, hypothyroidism, hypoparathyroidism, adrenal insufficiency, diabetes mellitus (DM) are specified. We also illustrated potential endocrinopathy due to hematopoietic stem cell transplantation, including hypogonadism and adrenal insufficiency due to glucocorticoid therapy.

Central diabetes insipidus developing in a 6-year-old patient 4 years after the remission of unifocal bone Langerhans cell histiocytosis.

A six-year-old boy was referred with a one-and-a-half months history of polyuria and polydipsia. At the age of two, he had a single lytic bone lesion in his femoral head, diagnosed as Langerhans cell histiocytosis (LCH) by biopsy at another hospital. As no other affected organs were detected and the affected bone lesion was self-limited, he was not followed up afterward and was doing well. He was diagnosed with diabetes insipidus (DI) by confirming hypernatremia (Na: 148 mEq/l) with hyperosmolar serum (s-Osm 298 mOSM/kg) and inappropriately diluted urine (u-Osm 205 mOSM/kg). His polyuria and polydipsia improved dramatically using the perioral diuretic hormone, and other pituitary functions were not impaired. Magnetic resonance imaging revealed an enlarged pituitary stalk. Sensitive and specific biomarkers of germ cell tumors, including alpha-fetoprotein, placental alkaline phosphatase, and ß-hCG in the cerebrospinal fluid, were not detected, indicating relapse of LCH. Genetic analysis revealed a BRAF V600E mutation in the primary bone lesion. We recommend systematic follow-up of patients with a history of LCH, even non-CNS single-system single-site disease, especially with BRAF V600E mutation.

Marked clinical heterogeneity in congenital hyperinsulinism due to a novel homozygous ABCC8 mutation.

BACKGROUND: The most severe forms of congenital hyperinsulinism (CHI) are caused by inactivating mutations of two KATP channel genes, KCNJ11 and ABCC8. Unresponsiveness to diazoxide and need for subtotal pancreatectomy can usually be predicted by genetic form, particularly biallelic mutations in KATP channel genes. A few reports indicated marked clinical heterogeneity in siblings with identical biallelic mutations in ABCC8. The clinical heterogeneity in biallelic KATP CHI was speculated to be caused by epigenetic and environmental factors or related to differences in splicing factor machinery. OBJECTIVE: To elucidate the clinical pathophysiology, especially heterogeneity, among three cases with CHI caused by a homogenous novel mutation. PATIENTS AND METHODS: We report a case series that includes two siblings and one unrelated individual with CHI caused by a homogenous 1-bp deletion around the splice acceptor site at the exon 35 mutation of ABCC8, which exhibited markedly distinct phenotypes. To assess the effect of the mutation on splicing, we performed digital droplet polymerase chain reaction (ddPCR) on normal pancreas tissue and a patient's lymphocytes. RESULTS: ddPCR of ABCC8 cDNA revealed that expression of exon 35 and its upstream and downstream regions did not differ. These data suggested that clinical heterogeneity may not be caused by differences in splicing factor machinery. CONCLUSION: The phenotypic variation in homozygotes could not be explained by splicing abnormalities. Though early genetic diagnosis of KATP CHI could contribute to selecting appropriate therapeutic options, more deliberate selection of therapeutic options in diffuse CHI due to biallelic ABCC8 mutations may be required.

Functional analysis of novel A20 variants in patients with atypical inflammatory diseases.

BACKGROUND: A20 haploinsufficiency (HA20) is an early-onset autoinflammatory disease caused by mutations in the TNFAIP3 gene, which encodes the protein A20. Numerous truncating mutations in the TNFAIP3 gene have been reported in HA20 patients, whereas fewer missense variants have had their pathogenicity confirmed. Here, we evaluated the pathogenic significance of three previously unreported missense variants of the TNFAIP3 gene in suspected cases of HA20. METHODS: We obtained the clinical features and immunological data of three patients with missense variants (Glu192Lys, Ile310Thr, and Gln709Arg) of unknown significance of TNFAIP3. We then performed in vitro functional assays including analysis of nuclear factor (NF)-κB reporter gene activity, detection of A20 expression and phosphorylation of A20 by IκB kinase ß (IKKß), and K63-deubiquitination assay using TNFAIP3-deficient HEK293 cells. Three known pathogenic missense mutations reported previously were also investigated. RESULTS: The inhibitory effect on NF-κB reporter gene activity was significantly disrupted by A20 Glu192Lys and the three known mutations. The variants Ile310Thr and Gln709Arg did not show a difference from the wild type in any of the assays performed in this study. CONCLUSIONS: Among the three variants in the TNFAIP3 gene, Glu192Lys was interpreted as being likely pathogenic, but Ile310Thr and Gln709Arg as being not pathogenic (uncertain significance and likely benign, respectively), based on the American College of Medical Genetics and Genomics standards and guidelines. Our study highlights the necessity of performing in vitro functional assays, notably, NF-κB reporter gene assay, to evaluate the pathogenicity of TNFAIP3 missense variants for the accurate diagnosis of HA20.

A case of ezetimibe-effective hypercholesterolemia with a novel heterozygous variant in ABCG5.

Sitosterolemia is caused by homozygous or compound heterozygous gene mutations in either ATP-binding cassette subfamily G member 5 (ABCG5) or 8 (ABCG8). Since ABCG5 and ABCG8 play pivotal roles in the excretion of neutral sterols into feces and bile, patients with sitosterolemia present elevated levels of serum plant sterols and in some cases also hypercholesterolemia. A 48-year-old woman was referred to our hospital for hypercholesterolemia. She had been misdiagnosed with familial hypercholesterolemia at the age of 20 and her serum low-density lipoprotein cholesterol (LDL-C) levels had remained about 200-300 mg/dL at the former clinic. Although the treatment of hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors was ineffective, her serum LDL-C levels were normalized by ezetimibe, a cholesterol transporter inhibitor. We noticed that her serum sitosterol and campesterol levels were relatively high. Targeted analysis sequencing identified a novel heterozygous ABCG5 variant (c.203A>T; p.Ile68Asn) in the patient, whereas no mutations were found in low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), or Niemann-Pick C1-like intracellular cholesterol transporter 1 (NPC1L1). While sitosterolemia is a rare disease, a recent study has reported that the incidence of loss-of-function mutation in the ABCG5 or ABCG8 gene is higher than we thought at 1 in 220 individuals. The present case suggests that serum plant sterol levels should be examined and ezetimibe treatment should be considered in patients with hypercholesterolemia who are resistant to HMG-CoA reductase inhibitors.

WDR11 is another causative gene for coloboma, cardiac anomaly and growth retardation in 10q26 deletion syndrome.

10q26 deletion syndrome is caused by a rare chromosomal abnormality, and patients with this syndrome present with an extensive and heterogeneous phenotypic spectrum. Several genes, such as EMX2 and FGFR2, were identified as the cause genital anomalies and facial dysmorphism in 10q26 deletion syndrome. However, the critical region for 10q26 deletion syndrome is not determined and the precise relationships between the causative genes and the phenotypes are still controversial. WD repeat domain 11 (WDR11), located at 10q25-26, was recently identified as a causative gene in hypogonadotropic hypogonadism, but other clinical phenotypes caused by WDR11 variants have not been identified. In this study, we have identified a WDR11 missense mutation, NM_018117.11: c.2108G > A; p.(Arg703Gln); ClinVar accession SCV000852064, in a two-year-old boy with severe growth retardation, ventricular septal defect, and coloboma symptoms. The case suggests that WDR11 is partially responsible for the clinical features of 10q26 deletion syndrome and provides novel insights into the pathophysiology of this syndrome.

A case of generalized lipodystrophy-associated progeroid syndrome treated by leptin replacement with short and long-term monitoring of the metabolic and endocrine profiles.

We herein report a case of a 28-year-old man with generalized lipodystrophy-associated progeroid syndrome treated by leptin replacement. He showed symptoms of generalized lipodystrophy around onset of puberty. His body mass index was 11.9 kg/m2, and he had a short stature, birdlike facies, dental crowding due to micrognathia, partial graying and loss of hair, and a high-pitched voice, all of which are typical features of the progeroid syndrome. Laboratory examinations and abdominal ultrasonography revealed diabetes mellitus, insulin-resistance, dyslipidemia, decreased serum leptin levels (2.2 ng/mL), elevated serum hepatobiliary enzyme levels and fatty liver. Whole exome sequencing revealed de novo heterozygous LMNA p.T10I mutation, indicating generalized lipodystrophy-associated progeroid syndrome, which is a newly identified subtype of atypical progeroid syndrome characterized by severe metabolic abnormalities. Daily injection of metreleptin [1.2 mg (0.04 mg/kg)/day] was started. Metreleptin treatment significantly improved his diabetes from HbA1c 11.0% to 5.4% in six months. It also elevated serum testosterone levels. Elevated serum testosterone levels persisted even 1 year after the initiation of metreleptin treatment. To the best of our knowledge, this is the first Japanese case report of generalized lipodystrophy-associated progeroid syndrome. Furthermore, we evaluated short and long-term effectiveness of leptin replacement on generalized lipodystrophy by monitoring metabolic and endocrine profiles.