Diagnostic Approach to Anemia in Adult Females

Understanding Iron Deficiency and Anemia

The American Gastroenterological Association recommends that any level of anemia should be investigated in the presence of iron deficiency, as iron deficiency can cause symptoms even before hemoglobin drops below 12.0 g/dL 1, 2
Serum markers of iron deficiency include low ferritin, low transferrin saturation, low iron, raised total iron-binding capacity, and increased serum transferrin receptor, according to the European Society of Gastrointestinal Endoscopy 1, 2
Iron deficiency without anemia is a recognized clinical entity that requires investigation and treatment, as stated by the World Health Organization 1

The European Society of Gastrointestinal Endoscopy recommends checking complete iron studies immediately, including ferritin, transferrin saturation, serum iron, and TIBC, in patients with symptoms and hemoglobin 13.3 g/dL 1, 2, 4
If any iron parameter is abnormal, the American College of Gastroenterology recommends proceeding with full investigation for the source of iron loss 1
The International Society of Sports Nutrition suggests considering checking reticulocyte hemoglobin content for early functional iron deficiency 1, 2

The American Gastroenterological Association recommends evaluating for chronic disease, including inflammatory markers, renal function, and thyroid function, in patients with iron deficiency 1, 2
The European Society of Gastrointestinal Endoscopy suggests reviewing medications, particularly NSAIDs, which commonly cause occult GI bleeding 1, 2, 4

The American College of Gastroenterology recommends pursuing GI investigation if iron deficiency is confirmed, even in premenopausal women, as 60-70% will have a GI source identified on endoscopy 1, 2, 4
Dual pathology (upper and lower GI bleeding sources) occurs in 1-10% of patients and increases with age, according to the World Health Organization 1, 2, 4