Endocrine Abstracts

Backgound: Adrenal incidentalomas (AI) are lesions that are incidentally identified while scanning for other conditions. The European Society of Endocrinology guidelines recommend that all patients with AI should undergo an overnight dexamethasone suppression test (ONDST) for the evaluation of autonomous cortisol secretion as defined by failure of suppression of cortisol to < 50 nmol/l. The reported prevalence of this is high (50% of patients in a recent publication) and m...

Introduction: Chromogranin-A (CgA) is a 49 kDa protein of the granin/secretogranin family originating from dense-core secretory granules within cells of the diffuse endocrine system. CgA is currently the best available diagnostic biomarker for neuroendocrine tumours (NETs) with recent clinical guidelines advocating the measurement of CgA as part of the baseline biochemical profile in patients presenting with symptoms suspicious of a gastroenteropancreatic NET.<p class="abs...

Introduction: The stress response post-operatively increases glucocorticoid concentration and a higher cortisol response is associated with better recovery. The measurement of cortisol concentrations post-operatively can be unreliable due to altered binding protein concentrations. Free serum cortisol is felt to be the better marker of bio-active glucocorticoid concentrations but is difficult to measure. Salivary cortisol and cortisone have been shown to correlate well with ser...

The accurate measurement of cortisol by immunoassay is compromised by the potential for cross-reactivity of reagent antibodies with structurally-related steroid compounds present in patient serum. This susceptibility is potentiated when normal steroid metabolism is altered pharmacologically by anti-steroidogenic drugs. This class of drug is utilised in the management of Cushing’s syndrome to moderate cortisol production. To investigate the effect of the 11β-hydroxyla...

Objective: Androsterone glucuronide (ADTG) concentrations have been suggested as a more reliable marker of the effects of androgen at the target tissue level and is significantly elevated in hirsute compared to non-hirsute women with PCOS. As the mechanism for hyperandrogenemia in obese and nonobese PCOS may differ, this study compares the different precursors of testosterone, including DHEAS, ADTG and androstenedione in nonobese compared to obese women with PCOS and their imp...

Comprehensive multi-steroid profiling offers a powerful tool for the investigation, diagnosis and management of steroidogenic disorders by simultaneously quantifying multiple steroids from several pathways of steroid biosynthesis and metabolism. Difficulties can arise when optimising chromatography and mass spectrometry conditions for many analytes in a single method. Low concentrations of ammonium fluoride have previously been shown to enhance the sensitivity of select analyt...

Background: Development of multi-steroid profiling allows comprehensive investigation into the different branches of steroid metabolism. Immunoassays only allow analysis of a single steroid per assay and suffer from problems with specificity due to cross reactivity of similar steroids. Liquid-chromatography mass spectrometry has the specificity to analyse multiple steroids in a single experiment and the dynamic range to quantify steroids at high concentrations such as those ob...

Background: Excess testosterone in PCOS is accompanied by increased levels of other ovarian and adrenal androgens and precursors. Recently, 11-oxygenated adrenal androgens have been postulated as major components of the circulating androgen pool in PCOS. Obesity is strictly connected with androgen excess and with the derangement of hormone circadian rhythmicity. To date, it has not been clarified whether hyperandrogenism in PCOS, either complicated by obesity or not, is accomp...

Introduction: Hydrocortisone therapy in adrenal insufficiency and medical management of Cushing’s syndrome requires accurate monitoring of glucocorticoid status. Currently, this necessitates admitting patients to hospital for serial measurements of serum cortisol. From previous studies in Cushing’s, the goal of medical therapy is a mean (based on five samples) serum cortisol of 150–300 nmol/l, which is known to equate to a normal cortisol production rate. Saliva...

Background: NEQAS data demonstrate a divergence in bias of cortisol immunoassays over the last 10 years. Despite this, a serum cortisol of 50 nmol/l has been universally applied as the cut-off for the overnight dexamethasone suppression test (ONDST), the commonest screening test for Cushing’s syndrome.Aims: To assess the effect of assay bias on interpretation of the ONDST and determine the necessity for a method-specific cut-off.<p class="abstex...