Parallel session
Chair: Sophie Barnes
This symposia will cover a variety of endocrinology topics: utility of copeptin in DI, use of serum 21-deoxycortisol in CAH and using LC-MS/MS for thyroglobulin.
11.30 - 12.00 - Using copeptin to improve the diagnosis of AVP disorders - Chris Boot
Diagnosis of central and nephrogenic diabetes insipidus (AVP deficiency and AVP resistance) in patients with polyuria/polydipsia can be challenging. Traditionally the ‘indirect’ water deprivation test (WDT) has been used to differentiate primary polydipsia, AVP deficiency and AVP resistance. However, there is growing evidence that ‘direct’ tests of AVP function using copeptin as a marker of AVP secretion can offer improved diagnostic performance compared to the traditional WDT approach. This talk will include a discussion of the evidence supporting the use of various tests in the diagnosis of AVP disorders and practical advice on how to use copeptin in the investigation of patients with polyuria/polydipsia.
12.00 - 12.30 - Improving the measurement of thyroglobulin using mass spectrometry: Is there hope for the future? - Ally Matthews
Measurement of thyroglobulin is recommended for the monitoring of residual, recurrent or metastatic disease in patients with differentiated thyroid cancer following treatment with thyroidectomy and/or ablative doses of radioiodine. Immunoassays are commonly employed by clinical laboratories to measure thyroglobulin. This talk will discuss the current challenges of thyroglobulin measurement using immunoassays and will address how mass spectrometry can be used to overcome these interferences, with the overarching aim of improving patient management.
12.30 - 1.00 - Congenital adrenal hyperplasia: time to change from 17-hydroxyprogesterone to 21-deoxycortisol measurement? - David Taylor
Measurement of 17-hydroxyprogesterone (17OHP) in serum is primarily used to diagnose a disorder of the adrenal glands, congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD). Unfortunately, 17OHP suffers with specificity issues, as it is increased in other physiological (preterm infants and in the luteal phase of the menstrual cycle) and pathophysiological (other forms of CAH) conditions. From our experience of running a urine steroid profiling service, we have long known that increase of the urinary 21-deoxycortisol (21DO) metabolite 11-oxo-pregnanetriol specifically secures 21OHD CAH diagnosis. 21DO, as a product of adrenal 11β-hydroxylase activity on 17OHP, is only synthesised by the adrenal glands (and not by the gonads like 17OHP). It is also not increased in preterm infants or other forms of CAH. It has been recommended that serum 21DO measurement should replace 17OHP for investigation of 21OHD CAH, but its introduction has been hampered in the U.K by a lack of laboratories offering the test. Our laboratory recently rolled out serum 21DO testing. In this talk, the evidence for 21DO measurement will be reviewed and real life experience of use of this test shared, in order to demonstrate its superior clinical utility for 21OHD CAH diagnosis.