Endocrine Abstracts

Background: Neuroendocrine tumours are rare tumours that arise from neuroendocrine cell types which are widespread throughout the body. These tumours can develop in many different organs and secrete a variety of hormones making biochemical monitoring of treatment/progression challenging. Previously patients at Beatson West of Scotland Cancer Centre were monitored using either a full gut hormone profile (GHP) or chromogranin A and B (CGs) measured at Charing Cross Hospital. A n...

A recent audit of the urine steroid profile (USP) service at Glasgow Royal Infirmary (GRI) revealed that up to 25% of requests are made inappropriately, or without any clinical information. In contrast to the majority of biochemical testing, USP analysis is very labour intensive, and interpretation of results requires both quantitative and qualitative assessment of the profile. Adequate clinical information is essential to generate a complete report, as a number of steroids fo...

Background: Chromogranin A is an acidic 48 kDa glycoprotein originating from the chromaffin granules of most neuroendocrine cell types. In health chromogranin A is released as a pro-hormone together with other peptide hormones in response to stimulation. In disease larger quantities of Chromogranin A are produced by neuroendocrine derived tumours thus allowing its use as a tumour marker. Due to the different clinical scenarios for measuring Chromogranin A requesting practices ...

Background/aims: Thyroglobulin (Tg) is used for monitoring patients who have undergone total thyroidectomy (TT) and radioiodine (RAI) ablation therapy for thyroid cancer. The current method is the Siemens Immulite assay with limit of quantification of 2 ng/mL following in-house evaluation. Recent guidelines suggest the use of high sensitivity Tg (hs-Tg) as an alternative to TSH stimulated Tg levels. The aim is to evaluate the hs-Tg Beckman Access II assay with a stated functio...

Background/aims: The short synacthen test (SST) is a dynamic function test used to assess the hypothalamic pituitary adrenal axis. Interpretation requires consideration of sample timing and cortisol method. Currently the 30 minutes post-synacthen cortisol (CORT30) at NHS Greater Glasgow and Clyde (NHS GGC) is >450 nmol/l measured on the Abbott Architect. A large reference range study published a cut-off of >430 nmol/l for this method. This audit aims to document clinic...

Concerns on the noncomparibility of intact parathyroid hormone (iPTH) methods have recently been voiced (Cantor T et al; Clin Chem 2006, 52, 1771–6). It is therefore important that any new iPTH immunoassays are thoroughly validated before routine use. We describe performance characteristics for an iPTH immunoassay on the ARCHITECT 8200i analyser as compared with iPTH measurement on the Diasorin LIAISON platform. Potassium EDTA plasma samples (n=80) we...

Background: Primary aldosteronism is an increasingly recognised cause of hypertension, caused by excess aldosterone secretion. Screening and confirmatory tests such as saline suppression tests (SST) require accurate measurements of aldosterone and use of appropriate cut-offs. Many laboratories have chosen liquid chromatography tandem mass spectrometry (LC-MSMS) methods as issues of poor specificity have been reported for immunoassay methods. During the validat...

Introduction: C-peptide is frequently used in clinical practice to estimate insulin secretion, and guide need for future insulin treatment. Present practice is based on studies with small patient numbers.Aim: To explore the association between non-stimulated c-peptide and progression to insulin therapy in patients with diabetes.Patients and Methods: 1971 patients with c-peptide measurements were identified (February 2007–Decem...

Bilateral inferior petrosal sinus sampling (BIPSS) is the gold standard investigation in Cushing’s disease for identifying the pituitary as the ACTH source. This technique aims to demonstrate a gradient of central:peripheral ACTH levels of >2:1 in such patients, or >3:1 after CRH stimulation. In patients without significant pituitary MRI abnormalities this facilitates neurosurgical exploration.The test is limited by difficulties in achieving...

Case History: We report the case of a 59-year-old lady with a persistently elevated serum thyroglobulin following a total thyroidectomy for multifocal papillary thyroid carcinoma. She subsequently underwent radioiodine therapy following which her serum thyroglobulin remained elevated. However, it was later found to be almost undetectable at 0.3 μg/l after a change in laboratory method. This discrepancy prompted further investigation, and repeat analysis using the original assa...