Endocrine Abstracts

Background: 5-hydroxyindole acetic acid (5-HIAA) (a metabolite of serotonin) is used as a marker for patients with serotonin-secreting neuroendocrine tumours. Currently, most laboratories measure 24 h 5-HIAA excretion in urine samples. Urine collections are cumbersome for the patient and impact on their daily activities; they are consequently often poorly performed, leading to over- or under-collection of urine and inaccurate 5-HIAA excretion results. Furthermore, large volume...

Background: The use of salivary cortisol is well validated in the diagnosis of Cushing’s syndrome but routine use of salivary measurements during dynamic tests of HPA axis sufficiency is uncommon and reference ranges are not established. Salivary cortisol (SalF) and cortisone (SalE) measurements by LC–MS have several advantages including ease of collection and more accurate reflection of unbound serum cortisol levels in conditions of altered CBG levels (e.g. oestroge...

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...

Background: The current screening test for adrenal insufficiency (AI) involves patients attending hospital for an “early” morning serum cortisol sample, generally taken some considerable time after the child has woken. This risks missing the morning cortisol peak, leading to false positive results. It requires venepuncture, which is unpleasant for children. Saliva collection is non-invasive, simple and can be undertaken on waking at home, providing a...

Objective: To investigate performance of sex hormone binding globulin (SHBG) assays of different manufacturers and the effects of assay choice on calculated free testosterone (cFT).Methods: Anonymized serum samples of 113 men and 106 women were randomly selected from excess material from the routine clinical lab at the University Hospital of South Manchester. SHBG levels were measured using three different immunoassays (...

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...