Endocrine Abstracts

Introduction: Biallelic mutations in the TSHB gene are a recognized cause of isolated congenital central hypothyroidism (CH), with autosomal recessive inheritance. In countries where neonatal CH screening relies on detection of an elevated TSH, such cases are missed, with the potential for delayed diagnosis and subsequent developmental impairment.Case: A female infant presented aged 8 weeks with prolonged jaundice, poor weight gain, constipation...

Introduction: Isolated congenital central hypothyroidism (CeCH) is a rare entity associated with mutations in IGSF1, TSHB, TRHR, or the coding region of TBL1X. We describe a female with CeCH and extrathyroidal features due to a partial X-chromosomal deletion involving TBL1X and other genes. Further studies showed markedly reduced TBL1X expression in patient-derived leukocytes and enabled linkage of particular clinical phenotypes to ...

Introduction: Thyroid function tests are frequently undertaken in children with non-specific symptoms suggestive of thyroid dysfunction. Infrequently, susceptibility of automated thyroid hormone assays to interference may generate misleading results, with the potential for inappropriate diagnosis and management. We report an unusual case with apparent subclinical hyperthyroidism, due to negative interference in particular TSH assay platforms, with an underlying genetic basis.<...

Alemtuzumab, a highly effective, newly-licensed, treatment for multiple sclerosis (MS), is notably associated with Graves’ disease (GD), which reportedly has an indolent course.Methods: Case record review of patients who developed thyroid dysfunction (TD) after alemtuzumab treatment in Cambridge & Cardiff, to determine type, frequency and course of TD.Results: 41.8% (104/249; 81F, 23M) of alemtuzumab-treated patients devel...

Peroxisome proliferator activated receptor gamma (PPARγ), a ligand-inducible transcription factor, is essential for adipocyte differentiation and lipogenesis. We previously described a kindred in which some individuals were heterozygous for a frameshift/premature stop mutation, (A553ΔAAAiT)fs.185(stop186) in PPARγ, with the truncated protein being non-functional and lacking dominant negative activity1. PPARγ null heterozygotes had norm...

Introduction: Less than 20% of congenital hypothyroidism (CH) has a known genetic aetiology; thyroid transcription factor mutations (PAX8, Nkx2.1, Nkx2.5, FOXE1) or biallelic TSHR mutations cause <5% of thyroid dysgenesis (TD), whereas mutations in genes mediating thyroid hormone biosynthesis (TPO, TG, DUOX2, DUOXA2, IYD, SLC5A5, SLC26A4) account for most dyshormonogenesis cases. Increased CH frequency in consanguineous populations, relatives of ...

Background: Lower cut-offs in TSH screening have doubled the incidence of congenital hypothyroidism (CH), particularly cases with an eutopically-located Gland-in-situ (GIS). Although mutations in known dyshormonogenesis genes, or the thyrotropin-stimulating hormone receptor (TSHR) may underlie such cases, these genes have not previously been screened comprehensively in a GIS CH cohort.Study design: We evaluated the relative contribution and mole...

Introduction: Congenital central hypothyroidism occurs either as isolated TSH deficiency or in conjunction with other pituitary hormone deficits. Undetected central hypothyroidism is associated with developmental delay in children and adverse cardiometabolic sequelae in adults. Hitherto, mutations in the TRH receptor (TRHR) or TSHβ subunit (TSHB) genes are the only known causes of isolated TSH deficiency.Methods: Using whole exome and candidate gene...

Introduction: Congenital central hypothyroidism occurs either as isolated TSH deficiency or in conjunction with other pituitary hormone deficits. Undetected central hypothyroidism is associated with developmental delay in children and adverse cardiometabolic sequelae in adults. Hitherto, mutations in the TRH receptor (TRHR) or TSHβ subunit (TSHB) genes are the only known causes of isolated TSH deficiency.Methods: Using whole exome and candidate gene...