Anemia in chronic illness: causes, symptoms, diagnosis, treatment

Anemia in chronic disease (anemia due to a violation of iron reutilization) is multifactorial and is often accompanied by iron deficiency. The diagnosis usually requires the presence of chronic infection, inflammation, cancer, microcytic or borderline-normocytic anemia, serum transferrin and ferritin values, which are determined in the values between typical for iron deficiency anemia and sideroblastic anemia. Therapy is aimed at treating the underlying disease, and if it is irreversible, reduces to the use of erythropoietin.

Around the world, anemia with chronic disease is the second most common. In the early stages, the erythrocytes are normochromic, but over time they become microcytic. The main problem is the inability of the erythroid bone marrow to proliferate in response to anemia.

[1], [2], [3], [4], [5]

Causes of the anemia in chronic disease

This type of anemia should be suspected in the presence of a chronic disease, more often an infectious, inflammatory process (especially rheumatoid arthritis) or a malignant neoplasm, but a similar process occurs with any infection or inflammation.

[6], [7], [8], [9], [10]

Pathogenesis

There are three pathophysiological mechanisms:

• moderate shortening of the lifetime of erythrocytes for as yet unknown reasons in patients with cancer or with chronic granulomatous infections;
• violation of erythropoiesis due to decreased production of EPO and bone marrow response to it;
• violation of intracellular iron metabolism.

Reticular cells retain iron obtained from old erythrocytes, making it inaccessible for hemoglobin synthesis; Thus, anemia can not be compensated by increasing the production of red blood cells. Macrophage cytokines (for example, IL-1, tumor necrosis factor a, interferon) in patients with infection, inflammation and cancer cause or contribute to a decrease in EPO production and disrupt iron metabolism.

[11], [12], [13], [14], [15], [16]

Symptoms of the anemia in chronic disease

Clinical manifestations, as a rule, are those that determine the underlying disease (infection, inflammation or malignant neoplasm).

[17], [18], [19], [20]

Diagnostics of the anemia in chronic disease

Anemia against a background of chronic disease is expected in patients with microcytic or borderline-normocytic anemia with chronic infection, inflammation or cancer. If there is a suspicion of chronic anemia, it is necessary to examine serum iron, transferrin, transferrin receptor and serum ferritin. The level of hemoglobin usually exceeds 80 g / l, until additional processes lead to the progression of anemia. If iron deficiency is present in addition to the chronic disease, the serum ferritin level is usually less than 100 ng / ml, and if in the presence of infection, inflammation or malignancy, the ferritin level is slightly less than 100 ng / ml, it is assumed that in parallel with the chronic disease caused by anemia there is iron deficiency. However, in view of the possibility of a false increase in serum ferritin level as an acute phase marker, in cases of high serum ferritin (> 100 ng / ml) in differential diagnosis of iron deficiency and anemia, the definition of a serum transferrin receptor helps in the background of a chronic disease.

[21], [22], [23], [24], [25]

Treatment of the anemia in chronic disease

The most important is the treatment of the underlying disease. Since the severity of anemia is usually weak, transfusions are generally not required and sufficient for the purpose of recombinant EPO. Taking into account both the decrease in the production of erythropoietin and the presence of bone marrow resistance to it, the dose of the latter can be increased from 150 to 300 U / kg subcutaneously 3 times a week. A good response is likely if after 2 weeks of therapy the hemoglobin level rises by more than 0.5 g / dl and serum ferritin is less than 400 ng / ml. The addition of iron is necessary to obtain an adequate response to EPO.