INTRODUCTION Traditional iron parameters often fail to distinguish the cause of iron-restricted anemia in patients without an obvious underlying cause. We evaluated whether an oral iron absorption test (OIAT) and hepcidin measurement could be useful diagnostic tests in these patients. METHODS We retrospectively analyzed data extracted from medical records of all patients who underwent an OIAT and hepcidin measurement, noting subsequent clinical diagnosis. Δ iron >15 µmol/L during the OIAT and hepcidin level below the median (or suppressed ≤0.5 nM) were considered appropriate. RESULTS Thirty-nine adult patients were included in the study. Sixteen patients with adequate OIAT had suppressed hepcidin levels indicative of classical iron-deficiency anemia (IDA); 59% of patients had abnormal OIAT. In this group, most patients with low hepcidin levels had anemia associated with abnormalities in the gastrointestinal tract, whereas 83.3% patients with high hepcidin levels had iron-refractory iron deficiency anemia (IRIDA), confirmed by genetic testing. Finally, transferrin/log ferritin ratio accurately identified patients with suppressed hepcidin: AUC 0.98 [95% CI: 0.95-1.02], P < 0.001. CONCLUSION OIAT differentiates between classical IDA and other types of anemia caused by abnormalities in iron absorption or systemic iron availability. Additionally, elevated hepcidin in patients with oral iron malabsorption could indicate IRIDA.

中文翻译：

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铁调素和口服铁吸收试验在确定铁限制性贫血的根本原因中的作用。

引言 对于没有明显根本原因的患者，传统的铁参数通常无法区分铁限制性贫血的原因。我们评估了口服铁吸收试验（OIAT）和铁调素测量是否可以作为这些患者有用的诊断试验。方法 我们回顾性分析了从所有接受 OIAT 和铁调素测量的患者病历中提取的数据，并记录随后的临床诊断。OIAT 期间 Δ 铁 >15 µmol/L 且铁调素水平低于中值（或抑制≤0.5 nM）被认为是适当的。结果 本研究纳入了 39 名成年患者。16 名具有足够 OIAT 的患者的铁调素水平受到抑制，表明典型缺铁性贫血 (IDA)；59%的患者OIAT异常。在该组中，大多数铁调素水平低的患者患有与胃肠道异常相关的贫血，而经基因检测证实，铁调素水平高的患者中有 83.3% 患有铁难治性缺铁性贫血 (IRIDA)。最后，转铁蛋白/对数铁蛋白比率准确地识别了铁调素抑制的患者：AUC 0.98 [95% CI：0.95-1.02]，P < 0.001。结论 OIAT 可区分经典 IDA 和由铁吸收或全身铁可用性异常引起的其他类型贫血。此外，口服铁吸收不良患者的铁调素升高可能提示 IRIDA。