Endocrine Abstracts

Objectives: The present study investigate the effect of light at night and rotating shift on circadian pattern of salivary cortisol and melatonin sulphate level in night shift workers and to find out whether these changes in the circadian pattern produce by night shift are reversible in due course of time. Sleep loss may be a novel risk factor for various hormones and sleep disturbances leads to metabolic and endocrinal disorders due to interference with diet, circadian metabo...

Case history: A 70 years old man with longstanding resistant hypertension on five antihypertensive agents, type two diabetes and raised BMI at 35.6 was referred to the endocrinology clinic for exclusion of possible Cushing’s disease. Clinically he had truncal obesity with plethoric face but no telangiectasia, easy bruising, purple striae or myopathy.Investigations: Endocrine examinations revealed normal 24 h urine free cortisol levels on two separat...

Aims: To assess the prevalence, investigations and management of hyponatraemia in hospital inpatients (previously deemed inadequate) over a 2-week period (1–15 May 2013) and compare with data collected in 2011, following the introduction of updated clinical guidelines in our trust.Methods: Hospital notes and electronic records of all patients with a sodium level of <130 mmol/l were analysed.Results: 43/255 (17%) patients h...

Introduction: The measurement of male androgens in most NHS laboratories is often limited to testosterone alone. To more accurately determine the androgen status in men the measurement of other androgens such as DHT and DHEA would be beneficial however these are difficult to measure without derivatisation. We report a combined LC–MS/MS assay for the measurement of testosterone, androstenendione, DHT and DHEA on a small sample volume.Methods: Zinc su...

Background: Kisspeptin is an RF amide peptide hormone critical for reproductive function. Kisspeptin is also abundantly expressed in the placenta, where it has an important physiological role in regulating placental invasion. Accordingly, plasma kisspeptin levels rise dramatically during normal pregnancy. Lower plasma levels of kisspeptin are associated with poor pregnancy outcomes such as recurrent miscarriage, intrauterine growth restriction and pre-eclampsia. Urinary measur...

Although TIH is a well-established complication of this drug class, the extent of this problem and the serious morbidity that can result is often not appreciated. At our centre, we became aware of three serious cases of TIH over a 2-week period during the ‘heat wave’ in July 2013. In at least one of these cases excessive water drinking was a clear precipitant. We therefore determined the incidence of TIH at our hospital and in particular whether there is a seasonal e...

Rationale: Over the last 20 years, granulocyte colony-stimulating factor (GCSF) has become a recognized therapy in the treatment of patients suffering from neutropenia. Current therapies require daily injections of GCSF to stimulate stem cell production and response to treatment is often unpredictable as GCSF is rapidly cleared. A number of approaches to reducing GCSF clearance have been tried mainly through conjugation with another moiety. The technologies already being emplo...

Background: Primary hyperparathyroidism (PHP) is the commonest cause of hypercalcaemia, with an annual incidence rate (AIR) of 4/100 000 and peak age incidence of 50–60 years. Our hospital serves a population with age ≥18 of around 500 000. A corrected calcium (cCa) ≥3.00 mmol/l is a critical phoning limit in our biochemistry laboratory.Aim: To assess the incidence of hypercalcaemia in the community, the referral pattern of hype...

Aims: Develop and validate a LC–MS/MS assay for the measurement of serum 17-hydroxyprogesterone (17-OHP) and to establish reference ranges for levels observed in the follicular and luteal phases of the menstrual cycle.Method: Serum samples (200 μl) underwent liquid extraction using di-ethyl ether (1 ml). A deuterated internal standard was used. 20 μl extract was injected onto a Waters Atlantis C18 column using a Waters 2795 Alliance HPLC s...

Background: Short synacthen test is used to assess adrenal function by injecting 250 μg of synacthen (tetracosactide) and measuring cortisol at baseline and subsequently after 30 and 60 min of the injection. In our hospital the cut-off for a normal test is a peak cortisol of 480 nmol/l or an increment of 200 or more from the baseline value.Methodology: We reviewed the results of 50 short synacthen tests performed in our hospital within the last year...

Objective: Biochemical assessment of male hypogonadism relies on estimation of freely available testosterone. Gold standard measurement is by equilibrium dialysis but this is not practical in clinical use. We compared two calculation methods; bioavailable (non-SHBG bound) testosterone (Morris et al.), and free (non-SHBG non-albumin bound) testosterone (Vermeulen et al.) for their diagnostic performance.Design: Free testosterone and bioa...

Phaeochromocytomas (PCC) and paragangliomas (PGL) are rare tumours derived from the sympathetic or parasympathetic paraganglia. They characteristically secrete catecholamines (noradrenaline/adrenaline/dopamine), which are metabolised to the metanephrines (normetadrenaline/metadrenaline/3-MT respectively). These tumour markers can be detected in acidified 24-h urine collections as first-line investigative tests. Plasma 3-MT has been characterised as a biomarker of metastatic PG...

Oral administration of chloroquine (CHQ) evokes adverse effects on glucose homeostasis and kidney function possibly due to transiently high plasma CHQ concentration or malaria. We have, however, reported that transdermally administered CHQ via the pectin CHQ-matrix patch formulation sustains controlled CHQ release into the bloodstream in experimental animals. Accordingly, the current study was designed to compare the ability of oral and transdermal CHQ treatments to clear para...

Background: The overnight dexamethasone (DEX) suppression test is useful for the investigation of hypercortisolism, however several factors may influence its performance. Intestinal uptake of DEX, inactivation by conversion by CYP3A4 in the liver and renal clearance can all affect test variability. It is also known that several drugs can either reduce or accelerate CYP3A4 activity, thereby affecting blood DEX concentrations. Interpretation of the test would be greatly enhanced...

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...

Three premenopausal patients presented with high isolated testosterone without symptoms of androgen excess or illicit drug use.Case 1: A 22-year-old female presented with daily vaginal bleeds having been on depot injections of progesterone with supplementary norethisterone. Testosterone was 14.5 nmol/l with suppressed gonadotrophins (LH <0.1 IU/l, FSH 0.2 IU/l, oestradiol <19 pmol/l). Her norethisterone was stopped. A repeat biochemical profile a...

Growing interest in the role of vitamin D in many disease conditions as well as wide availability of vitamin D assays has led to a marked increase in its measurement. Although there are multiple circulating metabolites of vitamin D, those of interest are 25-hydroxyvitamin D2 and D3 and measurements of their relative concentrations is considered helpful. We reviewed vitamin D levels (D2 and D3) obtained on our patient population visiting a large teaching hospital.<p class="...

Background: 5-hydroxyindole acetic acid (5-HIAA), a metabolite of serotonin, is used as a marker for patients with serotonin-secreting neuroendocrine tumours (NET). Currently, the majority of laboratories measure 5-HIAA excretion in 24 h urine samples. Given the practicality and analytic problems of these samples, our laboratory successfully developed a LC–MS/MS method for the analysis of 5-HIAA in serum samples. Further to this, we have now developed a method to measure ...

Measurement of cortisol is used in the differential diagnosis of Addisons’ disease (deficiency), Cushing’s disease (excess), hypopituitarism, adrenal hyperplasia and carcinoma. Cortisol is routinely measured by immunoassay, which has wide inter-assay variability with manufacturer dependent bias. Despite this, universal cut-offs are used as criteria for interpretation of dynamic function tests of the pituitary adrenal axis.Using a fully validate...

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...

Hyponatraemia is associated with adverse outcomes including increased mortality and risk of falls. It is not previously known whether hyponatraemia, on discharge from hospital, is associated with an increased risk of readmission.We conducted a retrospective cohort study identifying all patients admitted to a UK teaching hospital as emergency general medical admissions over a 2-month period. We identified all readmissions within 28 days of discharge and c...