Endocrine Abstracts

Background: Immune checkpoint (CTLA-4, PD-1) inhibitors are increasingly used to treat cancers including advanced melanoma. Although endocrine immune related adverse events (IRAEs) are now well reported, the frequency and type of thyroid and pituitary dysfunction reported varies considerably, with hypophysitis after CTLA-4 inhibitors reported in 2–16%, and thyroid dysfunction after PD-1 inhibitors in 2–39%. In addition, recove...

Context: Primary aldosteronism (PA) accounts for 5–10% of all hypertension and 20–25% of refractory cases. Diagnosis is important as PA is associated with increased morbidity and mortality compared with ‘essential’ hypertension, and up to 50% of patients may benefit from unilateral adrenalectomy. Screening requires measurement of plasma renin activity (PRA) or concentration (PRC), and plasma aldosterone concentration (PAC), to yield an aldosterone:renin rat...

Section 1: Case history: A 30 year-old female patient with a background of symptomatic primary hyperparathyroidism diagnosed in 2008 and a history of two failed neck surgeries, was reviewed in clinic complaining of persistent symptoms of hypercalcaemia. Previous pre-operative neck imaging had failed to localise a parathyroid adenoma and the patient had undergone two neck explorations by an experienced ENT surgeon; one which removed thymic tissue and the other which removed a m...

Introduction: Thyrotoxicosis resistant to the usual treatment is rare, but potentially fatal. In such situations, the optimal next treatment is unclear. Iopanoic acid (IA) was historically used as an oral contrast agent; it’s capacity to treat thyrotoxicosis has been limited in recent years due to its restricted availability.Methods: Retrospective case note review of patients treated with IA for resistant thyrotoxicosis at our institution over the p...

Case history: A clinically euthyroid 7-year-old boy was noted to have a persistently elevated TSH 7.35–14 mU/l (NR 0.27–4.2) and normal FT4 15.0 pmol/l (NR 10-24) with negative anti-thyroid peroxidase antibodies. Thyroid ultrasonography revealed a eutopically-located thyroid gland of normal size. Following commencement of levothyroxine, he developed insomnia, irritability and headaches, resulting in cessation of treatment. Growth and development proceeded ...

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: Thyrotropinomas (TSHomas) are traditionally considered a rare albeit important cause of thyrotoxicosis, accounting for ∼1% of all pituitary adenomas. Although early case series reported a preponderance of macroadenomas, emerging evidence suggests microadenomas are being increasingly diagnosed. In addition, the clinical/biochemical phenotype appears to be more variable than previously suspected. We therefore examined the clinical, metabolic, biochemical and ra...

Resistance to thyroid hormone (RTH) is usually due to heterozygous mutations in THRB gene with rare cases being homozygous for receptor defects. We describe an RTH case due to a homozygous TRβ mutation (R243Q).The Proband (male, 8.4 years), was born at term with low birth weight (1.9 kg) to consanguineous parents. He has a prominent nasal bridge, goitre, low body weight (10th centile), recurrent tonsillitis, hyperactivity and has mild hearing impair...

A 42-year-old man with resistance to thyroid hormone (RTH) and a recognised thyroid hormone receptorβ mutation (R383C) mutation, presented with atrial fibrillation (AF) which was resistant to DC cardioversion until initiation of amiodarone therapy.As expected in RTH, his baseline TFTs were abnormal (FT4 34.6 pmol/l, TSH 2.27 mU/l), but rose further (FT4 45 pmol/l, TSH 0.93 mU/l) following commencement of amiodarone. However, sh...

Corepressors and coactivators of thyroid hormone receptor-mediated function facilitate repression and transactivation of positively-regulated target genes respectively, but their role in negative regulation is not understood. A 13 yr old boy, born at 31 weeks gestation, was jittery at birth, with neonatal respiratory distress. Childhood features included poor weight gain, heat intolerance, tachycardia and hyperactivity. Ongoing problems are low frequency hearing loss, poor sig...