SFEBES2018 Featured Clinical Cases Featured Clinical Cases (10 abstracts)
Thyroid hormone pattern in Familial Dysalbuminemic Hyperthyroxinemia (R218H mutation) on different assay platforms
Serena Khoo 1 , Greta Lyons 1 , Anne McGowan 1 , Mark Gurnell 1 , Susan Oddy 2 , David Halsall 2 , Krishna Chatterjee 1 & Carla Moran 1
1Wellcome-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK; 2Department of Clinical Biochemistry, Addenbrooke’s Hospital, Cambridge, UK.
Introduction: Familial dysalbuminemic hyperthyroxinemia (FDH) is characterized by artefactual hyperthyroxinemia caused by enhanced binding affinity of thyroxine to the mutant albumin. However little is known about how FDH affects the measurement of thyroid hormones, especially FT3, across many assay platforms.
Methods: Forty-eight genetically confirmed FDH patients (R218H mutation) had FT4 and FT3 measured with 1-step (ADVIA CENTAUR®, Siemens IMMULITE® 2500, Roche ELECSYS E170) and 2-step (DELFIA®, Abbott Diagnostics (ARCHITECT®), VITROS, DIASORIN and BECKMAN) assays. Measured levels were compared to the upper limit of reference range. Patients with concomitant thyroid disease and assay interference were excluded.
Results: Both FT4 was raised in the majority of platforms (CENTAUR® 78.8–198.1% ULN, IMMULITE® 65.6–85.5% ULN, Roche 64.5–182.7% ULN, DELFIA® 62–132% ULN), as was FT3 (CENTAUR® 53.8–150.8% ULN, IMMULITE® 57.7–114.8% ULN, Roche 38.2–120.6% ULN, DELFIA 57.3–114.7% ULN). 100% denotes upper limit of reference range.
| ASSAYS | n | % FT4 Results Above ULN | n | % FT3 Results Above ULN |
| ADVIA CENTAUR® | 48 | 87.5 | 44 | 40.9 |
| Siemens IMMULITE® | 7 | 0 | 7 | 14.2 |
| Roche ELECSYS | 14 | 92.8 | 13 | 30.7 |
| DELFIA® | 48 | 47.9 | 36 | 25 |
| Abbott ARCHITECT® | 8 | 75 | 8 | 25 |
| VITROS | 7 | 0 | 7 | 0 |
| DIASORIN | 7 | 0 | 7 | 0 |
| BECKMAN | 8 | 100 |
Conclusion: Thyroid hormone measurements in FDH vary depending on assay performed. Siemens IMMULITE®, DIASORIN, and perhaps DELFIA® return FT4 levels nearer the normal range, while VITROS underestimates measurements. In contrast, results from Roche Elecsys, Beckman, Abbott ARCHITECT® and ADVIA Centaur® are markedly abnormal. Notably, FT3 levels are abnormal in up to 41% of patients, raising the possibility of confusion with TSHomas or Resistance to Thyroid Hormone.
Volume 59
Article tools
My recent searches
My recently viewed abstracts
Authors
Endocrine Abstracts
ISSN 1470-3947 (print) | ISSN 1479-6848 (online)
© Bioscientifica 2024 |
Privacy policy |
Cookie settings
BiosciAbstracts
Bioscientifica Abstracts is the gateway to a series of products that provide a permanent, citable record of abstracts for biomedical and life science conferences.
Find out more