Functional variants in a TTTG microsatellite on 15q26.1 cause familial nonautoimmune thyroid abnormalities.

Insufficient thyroid hormone production in newborns is referred to as congenital hypothyroidism. Multinodular goiter (MNG), characterized by an enlarged thyroid gland with multiple nodules, is usually seen in adults and is recognized as a separate disorder from congenital hypothyroidism. Here we performed a linkage analysis of a family with both nongoitrous congenital hypothyroidism and MNG and identified a signal at 15q26.1. Follow-up analyses with whole-genome sequencing and genetic screening in congenital hypothyroidism and MNG cohorts showed that changes in a noncoding TTTG microsatellite on 15q26.1 were frequently observed in congenital hypothyroidism (137 in 989) and MNG (3 in 33) compared with controls (3 in 38,722). Characterization of the noncoding variants with epigenomic data and in vitro experiments suggested that the microsatellite is located in a thyroid-specific transcriptional repressor, and its activity is disrupted by the variants. Collectively, we presented genetic evidence linking nongoitrous congenital hypothyroidism and MNG, providing unique insights into thyroid abnormalities.

Molecular and Clinical Features of Congenital Hypothyroidism Due to Multiple DUOX2 Variants.

Background: DUOX2 is one of the major causative genes of congenital hypothyroidism (CH). Still, the mutation spectrum and clinical outcomes of biallelic DUOX2 variants are not fully understood. This study aimed to elucidate the molecular features and long-term clinical manifestations of CH caused by multiple pathogenic DUOX2 variants. Methods: A total of 255 patients with CH were screened for rare variants of 11 known causative genes. DUOX2 variants were classified according to their protein structure and residual activity. In vitro assays were performed for several variants of unknown functions. Clinical analyses were conducted for patients with multiple pathogenic variants of DUOX2 but not of other genes. Results: We identified 24 pathogenic variants of DUOX2, together with two benign variants and seven variants of uncertain significance, in 63 patients. The pathogenic variants included three missense substitutions and one frameshift variant that have not yet been linked to CH. Twenty-one patients carried multiple pathogenic DUOX2 variants without any other pathogenic gene variants. Three of the 21 patients harbored homozygous variants. Family analysis, long-read amplicon sequencing, and haplotype phasing confirmed compound heterozygosity of the DUOX2 variants in 14 patients, whereas the allelic positions of the variants in the remaining four patients could not be determined. Of the 21 patients, 19 were treated with levothyroxine; their ages at drug withdrawal ranged from 9 months to 21.4 years. Three patients required retreatment after drug-free intervals of 6 months, 8 months, and 10 years. There were no differences in clinical severity among patients with DUOX2 amorphic/amorphic, amorphic/hypomorphic, and hypomorphic/hypomorphic variants. Conclusions: These results broaden the mutational spectrum of DUOX2. Furthermore, our data imply that patients with multiple pathogenic DUOX2 variants typically exhibit transient CH without significant genotype-phenotype correlations. Most importantly, this study demonstrated for the first time that these patients are at risk of developing recurrent hypothyroidism after a long drug-free interval.

Concurrent THRB and DUOX2 variants in a patient detected via newborn screening for congenital hypothyroidism: a case of resistance to thyroid hormone.

Most patients with resistance to thyroid hormone (RTH) test negative in newborn screening (NBS) for congenital hypothyroidism (CH). Here, we present a case of RTH diagnosed through NBS. The patient presented to us after her NBS for CH revealed high TSH (23.4 µIU/mL) and free T4 (FT4) (5.40 ng/dL) levels. Apart from tachycardia, she exhibited no other manifestations related to excess or deficiency of thyroid hormones. A confirmatory test replicated the findings, showing elevated serum TSH levels (35.7 µIU/mL) along with high FT4 levels (5.84 ng/dL). Ultrasonography showed marked thyroid gland enlargement (> +4 SD). Targeted next-generation sequencing of genes associated with genetic thyroid disorders revealed a previously reported THRB variant, p.Gly345Cys. Unexpectedly, two biallelic DUOX2 variants (p.His678Arg and p.Arg1334Trp) were also detected. At her last visit, no significant issues were observed with neurological development, growth, bone maturation, or gastrointestinal symptoms related to thyroid function at the age of 1 year, without treatment for RTH and CH. During follow-up, the TSH and FT4 levels gradually decreased. In conclusion, we report a patient with simultaneous RTH and DUOX2 defects, demonstrating the value of conducting a comprehensive analysis of multiple genes associated with thyroid diseases to better comprehend the pathogenesis in patients with atypical thyroid-related phenotypes.

Congenital Hypothyroidism with Thyroid in situ: A Case Report with NKX2-1 and DUOX2 Hypomorphic Variants.

INTRODUCTION: NK2 homeobox 1 (NKX2-1) encodes a transcription factor, NKX2-1, that is expressed in the thyroid gland, lung, and brain. Dual oxidase 2 (DUOX2) encodes an enzyme which generates hydrogen peroxide and is involved in the thyroid hormone synthesis. Cases of congenital hypothyroidism (CH) with dyshormonogenesis showing two or more genetic variants are increasingly reported. We describe the first case of transient dyshormonogenesis who had experimentally verified a loss-of-function NKX2-1 variant and DUOX2 variants. CASE PRESENTATION: The proband was a 15-year-old female patient with CH who was diagnosed in the frame of newborn screening for CH. She had a mildly elevated serum TSH level (14.56 mU/L), a low free thyroxine level (0.87 ng/dL), and a high thyroglobulin (Tg) level (>800 ng/mL). Ultrasonography revealed goiter. She was followed clinically without levothyroxine treatment and showed normal growth and development. She had slightly high Tg levels throughout the clinical course. Next-generation sequencing-based genetic analysis revealed that the patient was heterozygous for an NKX2-1 variant (p.Ile228Ser), a nonsense DUOX2 variant (p.[Lys530*;His678Arg]), and a functional DUOX2 polymorphism (p.His678Arg). NKX2-1 p.Ile228Ser showed about 50% reduced residual activity on the Tg promoter. CONCLUSION: A partial loss-of-function NKX2-1 variant with a monoallelic nonsense DUOX2 variant and a DUOX2 functional polymorphism can cause transient CH with high serum Tg levels.

Unbalanced Y;7 Translocation between Two Low-Similarity Sequences Leading to SRY-Positive 45,X Testicular Disorders of Sex Development.

Unbalanced translocations of Y-chromosomal fragments harboring the sex-determining region Y gene (SRY) to the X chromosome or an autosome result in 46,XX and 45,X testicular disorders of sex development (DSD), respectively. Of these, Y;autosome translocation is an extremely rare condition. Here, we identified a 20-year-old man with a 45,X,t(Y;7)(q11.21;q35) karyotype, who exhibited unilateral cryptorchidism, small testis, intellectual disability, and various congenital anomalies. The fusion junction of the translocation was blunt, and the breakpoint-flanking regions shared only 50% similarity. These results indicate that Y;autosome translocations can occur between 2 low-similarity sequences, probably via nonhomologous end joining. Furthermore, translocations of a Ypterq11.21 fragment to 7q35 likely result in normal or only mildly impaired male-type sexual development, along with various clinical features of 7q deletion syndrome, although their effects on adult testicular function remain to be studied.

Utility of follow-up blood cultures for Gram-negative rod bacteremia in children.

Persistent Gram-negative rod (GNR) bacteremia is uncommon under appropriate antibiotic therapy. A recent study showed that follow-up blood cultures (FUBCs) to confirm clearance 24-48 h after initiation of antibiotics, added little value in the management of GNR bacteremia in adults. However, the utility of FUBC in children is still unknown. We retrospectively reviewed the microbiology database to identify children aged <18 years with GNR bacteremia. Clinical information including gender, age, underlying diseases, presence of central venous line (CVC), source of bacteremia, and organisms was extracted from medical records. FUBCs for 99 episodes of GNR bacteremia in children became positive in 21%, which led to intervention in 57% of the episodes. In multivariate analysis between FUBC positive (n = 21) and negative (n = 78) groups, presence of CVC (n = 18, 86% vs n = 38, 49%, P = 0.001) and resistance to empirical antibiotics (n = 3, 14% vs n = 4, 5%, P = 0.04) were independently associated with positive FUBCs. Interestingly, no positive FUBC was observed in cases due to UTI (n = 13). Contrary to findings in adults, FUBC may still be useful in the management of GNR bacteremia in children.

Risk factors of long hospital stay for immunoglobulin A vasculitis: Single-center study.

BACKGROUND: Immunoglobulin A (IgA) vasculitis is a common, systemic childhood disease that occasionally interferes with oral intake of food and necessitates hospitalization. In Japan, there are no reports on the length of hospitalization or factors related to long-term hospitalization in children with IgA vasculitis. In this study, we investigated the factors related to long-term hospitalization. METHODS: We reviewed the medical records of children aged ≤15 years with IgA vasculitis who were admitted to the National Center for Child Health and Development (Tokyo, Japan) between March 2008 and April 2017. We reviewed their gender, age, previous episodes, digestive symptoms, fever, laboratory data, urine analysis, ultrasound, and use of glucocorticoid on admission day. We compared the long-stay (≥10 days) group (L) and the short-stay (≤9 days) group (S) on logistic regression analysis. RESULTS: Of the 68 children included in the analysis, 34 were male, and the average age was 71.9 ± 26.4 months. The median period of hospitalization was 10.5 days (range, 0.5-75 days), and 36 children were allocated to group L. In the logistic regression model including age, gender, gastrointestinal (GI) bleeding, and use of glucocorticoid, male sex (OR: 4.2; 95%CI: 1.3-13.5) and GI bleeding (OR: 7.6; 95%CI: 1.4-41.5) were significantly associated with hospitalization ≥10 days. CONCLUSIONS: In children with IgA vasculitis, male patients and those with GI bleeding were more likely to have a hospital stay ≥10 days.

Slow Elevation in Protein C Activity without a PROC Mutation in a Neonate with Intracranial Hemorrhage.

Severe protein C (PC) deficiency leads to purpura fulminans and stroke in newborns. However, the clinical impact of plasma PC activity on the development of neonatal cerebral disease remains elusive. We report a case of hemorrhagic stroke associated with neonatal asphyxia and severe PC deficiency. Plasma PC and protein S activity 7 days after birth was 12% and 43%, respectively. No PROC mutation was found. PC levels did not exceed 20% until 2 months of age, even in the absence of consumption coagulopathy or vitamin K deficiency. Neither thromboembolic nor hemorrhagic events occurred during the infusion of activated PC concentrate (twice weekly, up to 68 days after birth). The PC activity levels gradually increased to the standard value for age by 9 months of age. The present case showed that neonatal PC deficiency without a PROC mutation caused an intracranial hemorrhage before a slow increase in PC activity.

Upregulated expression of ADAM12 is associated with progression of oral squamous cell carcinoma.

ADAMs are a disintegrin and metalloproteinase family of membrane-associated metalloproteinases characterized by their multidomain structure, and have been reported to be associated with various malignant tumors. The aim of this study was to identify crucial members of the ADAM family in oral squamous cell carcinoma (OSCC), and to reveal their biological function and clinical significance. To clarify whether ADAM family genes are involved in OSCC, changes in the expression profile were investigated by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis and immunohistochemical analysis. Functional analysis was performed by comparing cellular proliferation of siADAM-transfected cell lines and parental cell lines. Real-time qRT-PCR analysis identified significantly upregulated expression of ADAM12 in OSCC-derived cell lines. This was validated in OSCC samples using real-time qRT-PCR and immuno-histochemical staining. ADAM12 expression was correlated with TNM classification; significantly greater expression of ADAM12 was observed in tumors with higher T classification and more advanced stages. Moreover, siADAM12-transfected cells showed both a suppressed proliferation rate and increased transforming growth factor (TGF)-ß3 expression. Our data indicate that ADAM12 is overexpressed in OSCC and might accelerate cellular proliferation. Its function may be associated with TGF-ß signaling. This study suggests that controlling the expression or activity of ADAM12 could be a useful strategy in the development of an effective cure for OSCC.