See also: Anemia: General Considerations.
Definition, Etiology, PathogenesisTop
Anemia of chronic disease (ACD) (also termed anemia of inflammation) is caused by decreased red blood cell (RBC) production due to an activated cellular immune response and by increased production of proinflammatory cytokines and hepcidin. It is the second most common anemia after iron deficiency anemia. Its incidence increases with age.
Causes: Acute or chronic infections, malignancy, autoimmune diseases (most frequently rheumatoid arthritis, systemic lupus erythematosus, and vasculitis syndromes), occult inflammatory conditions, selected drug therapies (eg, interferon treatment)
Clinical Features and Natural History Top
ACD usually manifests within a few months of the development of the underlying condition. Its severity increases with the severity of the causative disorder. Clinical manifestations include signs and symptoms of the underlying condition as well as general symptoms of anemia.
1. Complete blood count (Table. Differential diagnosis of hypochromic anemia…, Table. Differential diagnosis of anemia of…), normal or low reticulocyte counts, normal red cell distribution width.
2. Parameters of iron metabolism: Table. Differential diagnosis of hypochromic anemia…, Table. Differential diagnosis of anemia of….
3. Other tests: Abnormalities caused by the underlying condition, frequently increased levels of the markers of inflammation. Endogenous erythropoietin levels do not correspond to the severity of anemia.
Normocytic and normochromic anemia after other causes of anemia (particularly coexisting iron deficiency) have been excluded.
Iron deficiency anemia (Table. Differential diagnosis of hypochromic anemia…), other types of anemia (Table. Classification of anemias based on…).
1. Treatment of the underlying condition
2. Severe anemia: Transfusion of packed red blood cells (PRBCs).
3. Patients with anemia in the course of anticancer chemotherapy: Consider the use of an erythropoiesis-stimulating agent (ESA)—subcutaneous human recombinant erythropoietin alpha 40,000 U once weekly, subcutaneous human recombinant erythropoietin beta 30,000 U once weekly, or subcutaneous darbepoetin 500 microg every 3 weeks—titrated to increase hemoglobin to the lowest level sufficient to avoid PRBC transfusion. Contraindications and adverse effects: see Chronic Kidney Disease.
4. Absolute iron deficiency (serum ferritin <10 microg/mL) that may be observed in some patients with ACD should be treated with intravenous iron (see Iron Deficiency Anemia).