RT Journal Article
SR Electronic
T1 False elevation of serum cortisol in chemiluminescence immunoassay by Siemens Advia Centaur XP system in 21-hydroxylase deficiency: an ‘endocrine laboma’
JF BMJ Case Reports
JO BMJ Case Reports
FD BMJ Publishing Group Ltd
SP e235450
DO 10.1136/bcr-2020-235450
VO 13
IS 9
A1 Neeti Agrawal
A1 Partha Pratim Chakraborty
A1 Anirban Sinha
A1 Animesh Maiti
YR 2020
UL http://casereports.bmj.com/content/13/9/e235450.abstract
AB Liquid chromatography–mass spectrometry, the gold standard method for cortisol measurement, is expensive and not widely available in the developing countries. Chemiluminescent immunoassay, commonly used for cortisol measurement is prone to clinically meaningful inter-assay variability in some analysers. This occurs due to non-specific nature of anticortisol antibodies used in different platforms, having cross reactivity with structurally similar cortisol precursors like 17α-hydroxyprogesterone (17OHP), 11-deoxycortisol and 21-deoxycortisol. In patients with 21-hydroxylase deficiency, where 17OHP and 21-deoxycortisol are significantly elevated, older generation machines like Siemens Advia Centaur XP provide spuriously high cortisol concentration compared with values measured by Roche Cobas e 411 or Siemens Immulite 1000. Diagnosis of potentially life-threatening salt-wasting 21-hydroxylase deficiency may be missed and treatment may be delayed due to such interference. Two children with classic 21-hydroxylase deficiency are being reported here, in whom high cortisol values were observed in Siemens Advia Centaur XP system.