Diagnostic Approach and Management of Iron Deficiency Anemia

Initial Assessment and Diagnostic Approach

The British Society of Gastroenterology recommends confirming iron deficiency with iron studies including serum ferritin, transferrin saturation, and other markers before proceeding with invasive investigations 1
A complete blood count with red cell indices, reticulocyte count, and inflammatory markers should be obtained to characterize the anemia 1
Detailed history focusing on GI symptoms, menstrual patterns, medication use, and family history of bleeding disorders should be documented 2, 3

In patients with confirmed iron deficiency anemia without an obvious non-GI cause, both upper and lower GI tract investigations are recommended 2, 4
The British Society of Gastroenterology guidelines recommend upper GI endoscopy with small bowel biopsies for those with upper GI symptoms, and screening for celiac disease with antiendomysial antibodies for those without upper GI symptoms 5
Colonic investigation, such as colonoscopy, is recommended for those under 45 years with specific indications, such as severe anemia 5
Iron supplementation should be initiated promptly, with oral iron therapy aiming to correct anemia and replenish iron stores 4, 6
Treatment should continue for three months after correction of anemia to replenish iron stores 2

Failure to respond to iron therapy should prompt further investigation, including small bowel evaluation 4
The British Society of Gastroenterology guidelines emphasize that GI investigation should be considered on an urgent basis in adults with new diagnosis of IDA without obvious explanation 4
Dual pathology occurs in 10-15% of patients, highlighting the importance of complete evaluation 3