Synopsis
Recognise inflammation-related iron restriction and impaired erythropoiesis, exclude coexisting deficiency or marrow disease, and treat the underlying disorder while using specialist supportive therapy safely.
- Anaemia of inflammation is usually an underproduction anaemia caused by hepcidin-mediated iron sequestration, reduced erythropoietin effect and shorter red-cell survival; it is commonly normocytic but can become mildly microcytic.
- Make the diagnosis from a compatible active inflammatory, infective, malignant or renal disorder plus iron studies and reticulocytes. A raised CRP alone does not explain severe or progressive anaemia.
- Ferritin may remain normal or high because it is an acute-phase reactant, while transferrin saturation is low. This pattern indicates restricted availability but does not exclude coexisting absolute iron deficiency.
- Search for bleeding, B12 and folate deficiency, kidney disease, haemolysis, medicine toxicity and marrow pathology. Mixed causes are more common than a perfectly isolated inflammatory mechanism.
- Treating the underlying infection, inflammatory disease or cancer is the central intervention; improvement may lag because red-cell production and lifespan recover gradually.
- Do not give oral iron simply because serum iron is low. Establish whether absolute deficiency or a guideline-supported functional-iron indication exists and choose route through the relevant specialty pathway.
- Erythropoiesis-stimulating agents belong to defined chronic kidney disease and selected oncology pathways, with specialist targets, iron assessment and thrombotic or blood-pressure monitoring.
- Use red-cell transfusion for clinical oxygen-delivery need, not as routine long-term treatment of a stable laboratory value; reassess after each unit in adults without active bleeding.
Key red flags
Rapid progression, profound symptoms, additional cytopenias, abnormal cells, haemolysis or bleeding is not explained safely by a stable chronic inflammatory label.
Chest pain, syncope, resting breathlessness, heart failure, shock or active haemorrhage indicates threatened oxygen delivery and requires immediate support before mechanistic refinement.
Investigation priorities
Define severity, morphology, trajectory and adequacy of marrow output.
Management branches
Anaemia occurs alongside chronic inflammation, infection, malignancy or kidney disease without immediate physiological instability.
- Review the haemoglobin trajectory, symptoms, bleeding, medicines and active disease, then obtain FBC, film, absolute reticulocytes, ferritin, transferrin saturation, CRP, renal function, B12 and folate.
- The preferred interpretation integrates stores and inflammation: identify absolute deficiency, functional restriction, renal erythropoietin limitation and any bleeding or marrow warning features rather than naming one cause prematurely.
- Escalate rapid decline, additional cytopenias, haemolysis, abnormal cells or an explanation disproportionate to the known illness for urgent haematology and source-directed assessment.
Key medicines
Darbepoetin alfa (specialist CKD example)For adult CKD correction, start 0.45 micrograms/kg subcutaneously or intravenously once weekly; adults not on dialysis may instead start 0.75 micrograms/kg subcutaneously once every 2 weeks, with renal-protocol titration.Specialist initiation is required. Correct uncontrolled hypertension before treatment and monitor haemoglobin rate of rise, blood pressure, thrombosis, vascular-access events and iron availability; reduce or withhold according to the SmPC rather than chasing a normal haemoglobin.
Ferrous sulfate for coexisting absolute deficiencyGive one 200 mg tablet by mouth once daily; if gastrointestinal intolerance limits adherence, use one tablet every other day or a different standard oral preparation.A low serum iron alone is insufficient. Expect gastrointestinal effects and dark stools, separate interacting medicines using current BNF advice, keep tablets away from children and investigate non-response, bleeding or malabsorption.