Endocrine Abstracts

Introduction: Patients with complex health care needs and severely limited communication and mobility may be less likely to participate in research studies, and may find continued participation in such studies challenging. Allan Herndon Dudley syndrome (AHDS), due to defective thyroid hormone transporter (MCT8), causes severe neurological and physical disability. A multicentre trial (the TRIAC trial) studying the efficacy of the thyroid hormone analogue TRIAC in this rare cond...

Introduction: Familial dysalbuminemic hyperthyroxinemia (FDH) is characterized by artefactual hyperthyroxinemia caused by enhanced binding affinity of thyroxine to the mutant albumin. However little is known about how FDH affects the measurement of thyroid hormones, especially FT3, across many assay platforms.Methods: Forty-eight genetically confirmed FDH patients (R218H mutation) had FT4 and FT3 measured with 1-step (ADVIA CENTAUR®, Siem...

Background: The treatment of Resistance to Thyroid Hormone beta (RTHb) is challenging because no therapy restores the euthyroid state in all tissues. Triac (triiodothyroacetic acid), a centrally-acting thyroid hormone analogue that preferentially activates thyroid hormone receptor beta, is reported to be beneficial in case reports or small case series.Methods: We have treated a cohort of adult RTHb patients with hyperthyroid symptoms with Triac for upto ...

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 ...

The UK newborn screening programme for congenital hypothyroidism (CH) facilitates prevention of neurodevelopmental delay in CH by enabling prompt diagnosis and treatment. Although the UK Newborn Screening Programme Centre (UKNSPC) defines a borderline bloodspot screening TSH (bsTSH) concentration as 10–20 mU/l, the lower cutoff used at Great Ormond Street Hospital (6 mU/l), enables diagnosis of true and transient CH in cases missed using UKNSPC criteria. We hypothesised t...

Background: Hyperthyroxinaemia with non-suppressed TSH, due to resistance to thyroid hormone (RTH) or TSH-secreting pituitary tumour (TSHoma), can be difficult to diagnose, particularly with coincident autoimmune thyroid disease (AITD).Methods: To determine presentation patterns of AITD coincident with RTH or TSHoma, we analysed our cohort of cases with dual diagnoses.Results: Nine patients with RTH had AITD. Six had Graves’ d...

The UK newborn screening programme for congenital hypothyroidism (CH) facilitates prevention of neurodevelopmental delay in CH by enabling prompt diagnosis and treatment. Although the UK Newborn Screening Programme Centre (UKNSPC) defines a borderline bloodspot screening TSH (bsTSH) concentration as 10–20 mU/l, the lower cutoff used at Great Ormond Street Hospital (6 mU/l), enables diagnosis of true and transient CH in cases missed using UKNSPC criteria. We hypothesised t...

Background: The treatment of Resistance to Thyroid Hormone beta (RTHbeta) is challenging because no therapy restores the euthyroid state in all tissues. Triac (triiodothyroacetic acid), a centrally-acting thyroid hormone analogue that preferentially activates thyroid hormone receptor beta, is reported to be beneficial in case reports or small case series. Methods: We have treated a cohort of adult RTHbeta patients, all with heterozygous mutations in ...

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.<...

Background: Resistance to thyroid hormone (TH) beta (RTHβ), caused by mutations in THRB, is characterized by elevated serum (F)T4 accompanied by non-suppressed TSH concentrations. Disease features arise from variable resistance to TH action in tissues expressing Thyroid Hormone Receptor (TR) β (hypothalamus, pituitary, liver) and from thyrotoxic effects in tissues expressing TRα (heart, bone, brain). In symptomatic patients, treatment mainly involves be...