Endocrine Abstracts

Background: Thyroid stimulating hormone (TSH) and free T4 (fT4) were requested on a neonate, on Day 1 after birth. fT4 was flagged as below range, TSH was insufficient for analysis. Day 5-8 newborn bloodspot screening flagged a high TSH, hypothyroidism was confirmed, and thyroxine treatment commenced. Internal investigation into the incident, and the potential impact on the baby of delayed onset of treatment, raised the question of the relevance of our referen...

Background: The displacement of cortisol from its binding globulin (CBG) in the Abbott Alinity immunoassay assumes an average concentration of CBG in all individuals. Displacement buffer volume, and/or composition, is frequently insufficient to displace cortisol where higher concentrations of CBG are present (e.g. with higher oestrogen concentrations). To address this bias, the Eastern Pathology Alliance (EPA) introduced a 1:2 dilution step on all serum cortisol specimens in D...

Case 1: A 17-year-old female was referred to the endocrinology outpatients due to abnormal thyroid function tests (TFTs) (as below) detected on routine monitoring for Thyroxine replacement therapy. Following exclusion of pregnancy, possibilities of assay interference due to heterophilic antibodies as well as thyroid hormone resistance were considered. Repeat analysis was arranged at two laboratories using different methods. Results were concordant, excluding assay interference...

Background: The suitability of serum insulin-like growth factor 1 (IGF-1) reference ranges (RR) used locally (manufacturer-derived), were raised as a clinical concern. IGF-1 levels above the RR were reported in patients displaying no clinical signs or symptoms of acromegaly, and in whom growth hormone suppression tests were negative. No analytical issue was evident, and quality performance indicators were satisfactory.Methods: A review of all serum IGF-1...

Background: While investigating hyperandrogenism in women, local laboratory policy dictates adult females with a serum testosterone of >3.5 nmol/l should be confirmed with an alternative method to exclude interference by cross-reacting substances. Patients who were on testosterone replacement or had a previous result in the same year were excluded. We explore the biochemical investigation of discrepant testosterone in females.<strong...

Fibroblast growth factor 23 (FGF-23) is a phosphatonin produced by osteocytes in response to serum phosphate concentration. Immunoassays are widely employed to detect C-terminal fragments of FGF-23 (cFGF-23). Quantitative assays for intact FGF-23 (iFGF-23) measurement are also available. Causes of increased FGF-23 include Tumour Induced Osteomalacia (TIO), X-linked hypophosphataemic rickets (XLH) and end stage renal disease (ESRD). We observed that some individuals, with no id...

Introduction: In CKD, net effects of declining kidney function and increasing FGF23 (and PTH) concentrations on vitamin D catabolism and iron metabolism are not clear.Objectives: Compare the Biomedica to the Immutopics’ immunoassay for measurement of cFGF23. Determine the relationship between iron status; vitamin D and intact FGF23 (iFGF23) and c-terminal (cFGF23) concentrations in blood.Method: Samples from routine care and a...

Background: Adrenal incidentalomas (AI) are asymptomatic adrenal lesions found on imaging not primarily performed to detect adrenal disease. We conducted a retrospective audit of management of AI following European Society of Endocrinology recommendation (2016).Methods: This was a retrospective review of incidentaloma referrals over 9 months (June 2017–March 2018). Cases were identified using criterion search of the referral console. Additional data...

Introduction: Pheochromocytomas (adrenal and extra- adrenal/Paragangliomas) are rare catecholamine producing tumors and required complex dedicated MDTintervention. We preliminarily reported our service in a tertiary referral centre over 10 years (2008–2018).Method: A retrospectively review of confirmed phaeochromocytoma were carried out by reviewing clinical correspondences and ICE investigation-result system (laboratory, radiology and histology.)</...

Burosumab has become available as a treatment for children with X-linked hypophosphatemia (XLH) and is a recombinant fully human IgG1 against FGF23. By binding to the active FGF23, burosumab inhibits its effect and symptoms (growth retardation, rickets, enthesiopathy, low phosphate) may improve, however, not in all children. Concomitantly paediatricians are keen to measure FGF23, in treated children, to avoid overtreatment with burosumab, associated with potential calcificatio...