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Detection of iron restriction in anaemic and non-anaemic patients: New diagnostic approaches
Lothar Thomas1, Christian Thomas2
1Central laboratory for Clinical Chemistry and Hematology, University of Frankfurt, Frankfurt, Germany.
Objective:
The aim of this study was to detect iron restriction in non-anaemic patients and iron-restricted erythropoiesis (IRE) in patients with anaemia.
Method:
Haematologic indices and biochemical markers of iron deficiency (ID) were determined using the clinically accepted cut-off level for serum ferritin of ≤30 μg/L as reference of ID. To evaluate the prevalence of iron restriction and IRE in patients with higher ferritin levels, we used the thresholds of the markers of ID as reference.
Results:
In the anaemic group, 17.1% of patients with ferritin levels >30 μg/L had IRE. The number of patients with IRE declined with increasing ferritin concentration. Approximately 14% of patients without anaemia and ferritin levels >30 μg/L had iron restriction because of iron-sequestration syndromes. About 30% of the anaemic patients with IRE had ferritin concentrations in the range >300 μg/L, but no patient of the non-anaemic group.
Conclusions:
Detection of iron restriction and IRE in patients with ferritin levels >30 μg/L is not possible with a single test used in isolation. Based on the results, we have developed a scoring system to provide optimal guidance for the evaluation of iron restriction in non-anaemic patients and iron-restricted erythropoiesis (IRE) in patients with anaemia.
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