Vol 14 (2023): Continuous Publishing
Research paper
Published online: 2023-11-29

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Oral iron absorption test: myth or reality?

Samet Yaman1, Yağmur Kınacı Gümüşçubuk2, Oğuzcan Gümüşçubuk3, Berkan Karabuğa4, Sema Akinci4, İmdat Dilek4
Hematology in Clinical Practice 2023;14:35-40.


Introduction: Anemia is a serious health problem affecting one-third of the world's population. The most common etiology is iron deficiency anemia (IDA). The oral iron absorption test (OIAT) is a method that has been used for a long time to demonstrate the level of iron absorption in patients, but it has not reached widespread use in clinical practice. The study aims to analyze predictive factors of iron absorption in patients with IDA. Material and methods: A total of 108 patients between the ages of 18–65 who were diagnosed with IDA were included and patients with concomitant inflammatory bowel disease, celiac disease, history of gastrointestinal surgery, malignancy, using iron therapy, and patients with unavailable data were excluded from the study. OIAT applied to 108 patients. Results: Female patients form the majority of the cohort (n = 100, 92.6%). OIAT was administered to 54 patients in tablet form and 54 patients in capsule form. The following study compared 88 patients with adequate oral iron absorption and 20 patients with insufficient oral iron absorption. Less iron absorption was found in male patients (p = 0.04) with increasing age, and it was statistically significant (p = 0.02). Conclusion: The result of the current study demonstrated that male gender and older age have a significant impact on iron absorption. OIAT is recommended at the time of diagnosis in elderly patients and male patients so that the underlying cause can be identified without delay in the insufficient iron absorption group. Additionally, patients with oral iron absorption disorders can be diagnosed at an early stage by applying the OIAT. 

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Hematology in Clinical Practice