Cited by 101Iron Metabolism and DisordersClinical Laboratory Practices and Quality ControlHemoglobinopathies and Related Disorders

Results of an international round robin for the quantification of serum non-transferrin-bound iron: Need for defining standardization and a clinically relevant isoform

Jacobs, Esther M.G., Hendriks, Jan C.M., van Tits, Berry L.J.H., Evans, Patricia J., Breuer, William, Liu, Ding Yong, Jansen, Eugene H.J.M., Jauhiainen, Katri +7 more·2005·Analytical Biochemistry

Abstract

Non-transferrin-bound iron (NTBI) appears in the circulation of patients with iron overload. Various methods to measure NTBI were comparatively assessed as part of an international interlaboratory study. Six laboratories participated in the study, using methods based on iron mobilization and detection with iron chelators or on reactivity with bleomycin. Serum samples of 12 patients with hereditary (n=11) and secondary (n=1) hemochromatosis were measured during a 3-day analysis using 4 determinations per sample per day, making a total of 144 measurements per laboratory. Bland-Altman plots for repeated measurements are presented. The methods differed widely in mean serum NTBI level (range 0.12-4.32mumol/L), between-sample variation (SD range 0.20-2.13mumol/L and CV range 49.3-391.3%), and within-sample variation (SD range 0.02-0.45mumol/L and CV range 4.4-193.2%). The results obtained with methods based on chelators correlated significantly (R(2) range 0.86-0.99). On the other hand, NTBI values obtained by the various methods related differently from those of serum transferrin saturation (TS) when expressed in terms of both regression coefficients and NTBI levels at TS of 50%. Recent studies underscore the clinical relevance of NTBI in the management of iron-overloaded patients. However, before measurement of NTBI can be introduced into clinical practice, there is a need for more reproducible protocols as well as information on which method best represents the pathophysiological phenomenon and is most pertinent for diagnostic and therapeutic purposes.

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Crossref · 10.1016/j.ab.2005.03.008

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  • Later reports of HH pedigrees observed the C282Y mutation in both alleles of the HFE gene with a prevalence of between 60% and 100%.

    “Later reports of HH pedigrees also observed this mutation in both alleles of the HFE gene that encodes a tyrosine instead of the normal cysteine at codon 282 (C282Y), as having a prevalence of between 60% and 100% (40, 147, 150).”

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Authors
Jacobs, E. M. G., Hendriks, J. C. M., van Tits, B. L. J. H., Evans, P. J., Breuer, W., Liu, D. Y., Jansen, E. H. J. M., Jauhiainen, K., Sturm, B., Porter, J. B., Scheiber-Mojdehkar, B., von Bonsdorff, L., Cabantchik, Z. I., Hider, R. C., & Swinkels, D. W.
Affiliations
  • Radboud University Nijmegen (NL)
  • University College London (GB)
  • Hebrew University of Jerusalem (IL)
  • King's College London (GB)
  • Finnish Red Cross (FI)
  • University of Vienna (AT)
Corresponding author
Swinkels, Dorine W.
Venue
Analytical Biochemistry
Publisher
Elsevier BV
Published
2005-06
Volume
341
Issue
2
Pages
241-250
ISSN
0003-2697 (ISSN-L)
OpenAlex
W2117280779
Cited by
101
References
25
Citations by year
2025: 2 · 2024: 3 · 2023: 1 · 2022: 5 · 2021: 2 · 2020: 2 · 2019: 5 · 2018: 1 · 2017: 4 · 2016: 4 · 2015: 4 · 2014: 7 · 2013: 8 · 2012: 5
FWCI
4.53
Type
journal article
Language
en
Open access
closed
Locations
  • Analytical Biochemistry (publishedVersion)
  • PubMed (publishedVersion)
  • UCL Discovery (University College London) (submittedVersion)
  • Research Portal (King's College London) (submittedVersion)
  • Radboud Repository (Radboud University) (submittedVersion)
  • Rivm (National Institute for Public Health and the Environment) (submittedVersion)
Funders
Radboud Universitair Medisch Centrum
Topics
  • Health Sciences › Medicine › Hematology › Iron Metabolism and Disorders
  • Health Sciences › Medicine › Physiology › Clinical Laboratory Practices and Quality Control
  • Health Sciences › Medicine › Genetics › Hemoglobinopathies and Related Disorders
Keywords
non-transferrin-bound iron, iron overload, hemochromatosis, hereditary hemochromatosis, secondary hemochromatosis, interlaboratory comparison, method standardization, iron chelators, iron mobilization, transferrin saturation, measurement reproducibility
MeSH terms
Bleomycin, Blood Chemical Analysis, Chelating Agents, Hemochromatosis, Humans, Iron, Transferrin, Protein Isoforms

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