Anemia of chronic disease
Also called anemia of inflammation, can be caused by chronic inflammation, autoimmune and infectious disorders (human immunodeciency virus [HIV], hepatitis, malaria), HF, or malignant diseases. Bleeding episodes can also contribute to anemia of chronic disease.
Anemia of chronic disease is associated with an underproduction of RBCs and mild shortening of RBC survival. The RBCs are usually normocytic, normochromic, and hypo-proliferative. The anemia is usually mild, but it can become more severe if the underlying disorder is not treated. This type of anemia, which usually develops after 1 to 2 months of disease activity, has an immune basis. The cytokines released in these conditions, particularly interleukin 6 (IL-6), cause an increased uptake and retention of iron within macrophages and as a result this leads to a diversion of iron from circulation into storage sites with subsequent limited iron available for erythropoiesis.
Moving forward, there is also reduced RBC life span, suppressed production of erythropoietin, and an ineffective bone marrow response to erythropoietin. For example, with renal disease, the primary factor causing anemia is decreased erythropoietin, a hormone made in the kidneys that stimulates erythropoiesis. With impaired renal function, erythropoietin production is decreased.
What distinguishes it from other types of Anemias?
Findings of elevated serum ferritin and increased iron stores distinguish it from iron deficiency anemia. Normal folate and cobalamin blood levels distinguish it from those types of anemias.
The best treatment of anemia of chronic disease is correction of the underlying disorder. If the anemia is severe, blood transfusions may be indicated, but they are not recommended for long-term treatment.
Erythropoietin therapy is used for anemia related to renal disease and may be used for anemia related to cancer and its therapies.
NB* Erythropoietin therapy needs to be used conservatively because of the increased risk of thromboembolism and death in some patients.