How should I manage a patient with iron deficiency anemia, and when should I consider referral to a specialist?

Management of iron deficiency anemia (IDA) involves confirming iron deficiency, initiating appropriate iron therapy, monitoring response, and considering specialist referral when indicated.

First, confirm iron deficiency by assessing iron status using a combination of tests such as transferrin saturation (<20%) and serum ferritin (<100 µg/L), or reticulocyte hemoglobin content if available, rather than relying on ferritin or transferrin saturation alone, especially in chronic kidney disease (CKD) patients ¹.

For adults with IDA not on erythropoietic stimulating agents (ESAs), start with a trial of oral iron therapy, considering patient tolerance and preferences. If oral iron is not tolerated or target hemoglobin (Hb) levels are not achieved within 3 months, offer intravenous iron therapy, particularly in those with CKD or on hemodialysis, where intravenous iron is preferred ¹.

When iron deficiency anemia occurs in the context of CKD, iron therapy should be optimized before starting ESA therapy, as ESAs are ineffective without adequate iron stores ¹.

Monitor Hb and iron status regularly: Hb every 2-4 weeks during induction and 1-3 months during maintenance phases of ESA therapy, and iron stores every 1-3 months to avoid iron overload (serum ferritin should not exceed 800 µg/L) ¹.

Consider specialist referral in the following situations: if there is resistance to ESA therapy despite adequate iron repletion and high ESA doses, suspicion of pure red cell aplasia (PRCA), or if an underlying hematological disorder is suspected. Also, refer if blood transfusions are required frequently or if the diagnosis is unclear ¹.

Recent literature from Sub-Saharan Africa emphasizes the importance of gastrointestinal evaluation in iron deficiency anemia to identify and manage underlying causes such as bleeding or malabsorption, which may also apply in the UK context for unexplained or refractory cases (Simmonds et al., 2024).

Therefore, in primary care, manage IDA initially with appropriate iron therapy and monitoring, and consider referral to hematology or gastroenterology specialists when there is treatment resistance, suspicion of complex underlying pathology, or need for advanced investigations (e.g., endoscopy) (Simmonds et al., 2024; ¹).