Management of Iron Deficiency Anemia

Diagnostic Approach

The American Gastroenterological Association recommends that adults with iron deficiency anemia should undergo a comprehensive gastrointestinal evaluation to identify the source of blood loss, as this presentation warrants investigation for malignancy 1, 2
The European Society for Medical Oncology suggests that serum ferritin is the most powerful test for iron deficiency and should guide the diagnostic approach, with a level of <30 μg/L confirming iron deficiency in the absence of inflammation 2
The presence of elevated RDW reflects heterogeneous red cell populations with varying sizes as iron stores become depleted, and is a specific early indicator of iron deficiency 2, 3

The American College of Gastroenterology recommends that transferrin saturation <30% supports iron deficiency diagnosis, and C-reactive protein (CRP) is mandatory to interpret ferritin correctly, as inflammation elevates ferritin and can mask true iron deficiency 2, 3
A complete blood count with differential is necessary to evaluate other cell lines and confirm the pattern, and a reticulocyte count assesses bone marrow response 4

The British Society of Gastroenterology suggests that all adult men and post-menopausal women with confirmed iron deficiency require complete gastrointestinal evaluation, including upper endoscopy with small bowel biopsies and colonoscopy or CT colonography, regardless of symptom presence 1, 3
Small bowel biopsies are mandatory during endoscopy, as 2-3% of patients have celiac disease 1, 2, 3

The American Gastroenterological Association recommends initiating oral iron supplementation once iron deficiency is confirmed by ferritin testing, and continuing iron for 3-6 months after hemoglobin normalizes to replete iron stores 3, 4
Treatment of the underlying cause will cure the anemia, making identification of the source critical, and addressing any identified GI pathology (malignancy, inflammatory bowel disease, celiac disease, angiodysplasia) is necessary 1, 2

The European Society for Medical Oncology advises against assuming dietary deficiency alone without complete GI evaluation, as this can delay diagnosis of malignancy, and against empiric iron therapy without confirming iron deficiency with ferritin, as this can cause harm in conditions like thalassemia and delays proper diagnosis 1, 2, 3