Endocrine Abstracts

Background: 5α-Reductase (5αR) catalyses conversion of testosterone to its more potent metabolite dihydrotestosterone (DHT) and is inhibited when treating benign prostatic hyperplasia. 5αR has two isozymes; dual isozyme inhibition with dutasteride gives greater DHT suppression than finasteride, which inhibits only 5αR type 2.Aim: To develop a novel assay to simultaneously analyse testosterone, epitestosterone, DHT, androstenedione, du...

Background: 5α-Reductase type 2 deficiency (5ARD) is caused by mutations in the SRD5A2 gene. Inadequate masculinisation in XY individuals results from failure to convert testosterone (T) to dihydrotestosterone (DHT), a potent androgen. A decreased serum T:DHT ratio is frequently taken to identify 5ARD, but requires hCG stimulation for prepubertal patients; findings are not always supported by genotyping. Urine steroid profiling (USP) by GC-MS is established as showing sig...

Introduction: Methodological differences in the immunoassay measurement of cortisol are apparent when reviewing External Quality Assessment scheme data. A bimodal distribution is often observed, particularly for samples from female subjects. It has been postulated that some immunoassays are inefficient at removing cortisol from its binding proteins and therefore have the potential to under-recover from female samples. We investigated the results obtained from two immunoassays ...

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...

Objective: (1) To review normative data for catecholamines using our cohort of hyperaldosteronism patients undergoing adrenal vein sampling. This adds to the previously published data of normative values in a cohort of patients with cortisol-producing adenoma. (2) To demonstrate the usefulness of the noradrenaline to adrenaline ratio in the interpretation of adrenal venous sampling results.Design: 38 patients underwent successful, bilateral adrenal venou...

Introduction: SIADH is frequently observed as a paraneoplastic secretion in many cancer types with the highest frequency described in small-cell lung cancer. The paraneoplastic secretion of ADH/vasopressin may induce hyponatraemia which is associated with increased morbidity and mortality. Conventional treatment of the condition consists of fluid restriction and demeclocycline. Tolvaptan, an oral V2-receptor antagonist, that directly targets the mechanism of SIADH, has been pr...

Aims: To ascertain the incidence of hypo- and hyper-natraemia in patients admitted to a tertiary neurosurgical centre with confirmed spontaneous aneurysmal subarachnoid haemorrhage (SAH), and to determine their impact on length of hospital stay and mortality.Methods: Retrospective case note review of patients admitted between January 2008 and April 2011.Results: 402 patients with SAH were identified [mean (±sd</sma...

Introduction: Testosterone measurement by liquid chromatography tandem mass spectrometry (LC-MS/MS) is well accepted as the preferred technique for the analysis of serum testosterone in both males and particularly females. However variation is seen between LC-MS/MS assays and is most likely to be due to method differences between laboratories. One area of inconsistency amongst routine LC-MS/MS assays is the choice of internal standard. We investigated the effects of three inte...

An 87 year old gentleman with type 2 diabetes mellitus was started on oral sodium fusidate for infected left middle toe ulcer. His blood test revealed Sodium 140 mmol/L, potassium 5.2 mmol/L, urea 25.3 mmol/L, creatinine 287 µmol/L, eGFR-19 ml/minute, albumin 29 g/L, adjusted calcium 2.17 mmol/L, and phosphate 0.95 mmol/L. Two days later he was admitted to hospital. Blood tests on admission showed severe hypocalcaemia with renal failure. (Sodium 146 mmol/LL, potassium 4.9...

Background: Vitamin D deficiency is a common feature of primary hyperparathyroidism (PHP). However, replacement of vitamin D is not routinely performed in clinical practice, due to concerns about its safety. Furthermore, it is not clear whether vitamin D deficiency worsens the biochemical derangements observed in patients with PHP.Aim: To determine the relationship between 25(OH) vitamin D status and biochemical markers in patients with PHP.<p class=...

A 68 yr old male with a history of type 2 diabetes presented with myalgia and girdle weakness affecting him on a frequent but episodic basis. Investigations confirmed Cyclical Cushing's Disease. Pituitary MRI was normal. Further investigations include bilateral inferior petrosal sinus sampling (BIPSS) which can help determine the origin of ACTH-dependent Cushing’s syndrome. After CRH-stimulation, a peak central to peripheral ACTH ratio of >3 suggests a pituitary ACTH ...

Aim to elucidate the factors influencing length of stay (LOS) in patients with hyponatraemia admitted to an acute medical unit (AMU).Methodology: a prospective study of patients admitted to AMU at West Middlesex University Hospital from November 2009 to June 2011. A proforma was completed for each patient by the registrar on his duty days.Results: 70 patients were identified with a mean age of 69.2 years. 41 (59%) were female. 20 (...

This is a case of a 49 year old obese Caucasian female who was referred to an endocrinology clinic for investigation of Cushing’s syndrome, based on raised blood pressure and cushingnoid facies. The patient had underlying schizophrenia and was stable on clozapine. Her blood pressure was 150/99 mmHg on bendrofluoriomethiazide and candesartan. Her 24 hour urinary free cortisol was normal but 24 hour urinary free noradrenaline was elevated at 835 nmol (76–561) with norm...

Introduction: Prolactinoma and macroprolactin are important differentials in the diagnosis of hyperprolactinaemia. We present the case history of a patient with hyperprolactinaemia due to an unusual coincidence of macroprolactin and a non-enhancing pituitary lesion. Case history: A previously well female police officer aged 29, was referred to the endocrine clinic with a history of amenorrhoea and mastalgia for 3 years. She also complained of nausea, dizziness, weight gain, th...

Aim: To elicit the factors affecting the severity of Vitamin D deficiency (VDD) in an endocrine outpatient population in a district general hospital.Methodology: A retrospective analysis of serum 25-hydroxy vitamin D levels of all patients known to an endocrine clinic between 1st January 2009 and 30th June 2011. The first vitamin D level within this period was recorded. Other biochemical markers and co-morbidities were also studied.<p class="abstext"...