This document discusses anemia of chronic disease (ACD), also known as anemia of inflammation. It defines ACD as a mild to moderate anemia associated with chronic infections, inflammatory disorders, and some cancers. The document outlines the key characteristics of ACD, including inadequate red blood cell production, low serum iron, and low iron binding capacity. It also discusses the high prevalence of ACD, potential causes like infections and autoimmune disorders, and pathological features such as hepcidin-induced hypoferremia. The document provides guidance on differentially diagnosing ACD and notes that effective treatment of the underlying chronic condition can help resolve the anemia.
2. DEFENITION
The terms anemia of chronic disease or chronic disorders refer to mild to
moderately severe anemias ([Hb] 7-12 g/dl) associated with chronic
infections and inflammatory disorders and some malignancies.
The newer name for this anemia is anemia of inflammation(AI)
AI is characterized by:
Inadequate erythrocyte production
Low serum iron
Low binding capacity (i.e low transferrin)
The erythrocytes usually are normocytic and normochromic
but can be mildly hypochromic and microcytic.
3. EPIDEMIOLOGY
The high prevalence of infectious diseases worldwide and the
high prevalence of inflammatory and malignant disorders in the
industrialized countries suggest that AI is the second or third most
common form of anemia after iron-deficiency anemia (IDA) and
thalasemia .
4. ETIOLOGY
Infections (acute and chronic)
Viral infections, including HIV infection
Bacterial including tuberculosis, osteomyelitis and sepsis
Parasitic including malaria
Fungal
Cancer
Hematologic including multiple myeloma and lymphoma
Solid tumor including carcinoma
7. PATHOGENESIS
Red cell destruction
Inadequate erythropoietin secretion and resistance to erythropoietin
Erythropoiesis as a result of iron unavailability
Interleukin -6 ,Hepcidin ,and Hypoferremia
Serum iron concentrations are dependent on iron released from
Macrophages and Hepatocytes
Inhibition of Intestinal absorption of iron
8. CLINICAL FEATURES
The clinical manifestations of AI usually are obscured by the signs
and symptoms of the underlying disease.
Moderate anemia (Hg<10) can exacerbate the symptoms of the
preexisting ischemic heart disease or respiratory disease.
9. The erythrocytes in AI are normocytic and normochromic but
, with increasing severity and duration , can become
hypochromic and eventually microcytic.
The absolute reticulocyte count is normal or slightly elevated.
Hypoferremia and decreased serum transferrin
Interleukin -6 ,Hepcidin ,and Hypoferremia
Normal to increased serum ferritin
Marrow iron stain
10.
11.
12.
13. Hypoferremia and decreased serum
Transferrin
Hypoferremia , decrease in the serum iron concentration , is a defining feature of
AI .
Moderately decreased:
The decreased in transferrin concentration develops more slowly than the
decreas in the iron levels because of the longer half-life of transferrin (8-12 days )
compared to the half-life of iron ( approximately 90 minutes )
14. Increased serum ferritin
Serum ferritin concentrations , which reflects iron stores , are
increased in AI but decreased in Iron deficiency .
15. Marrow iron stain
Marrow aspiration or biopsy is rarely required for diagnosis of AI .
In general , the marrow morphology and stainable iron are normal ,
unless the underlying disease alters the picture .
The most important information that obtained from marrow
examination is the content of and distribution of iron.
16. DIFFERENTIAL DIAGNOSIS
Most patients with chronic infections , inflammatory diseases , or
neoplastic disorders are anemic.
The diagnosis of AI should be made only if the anemia is mild to moderate
,the serum and iron binding capacity are low , and the serum ferritin is
elevated .
Drug-induced marrow suppression or drug-induced hemolysis
Chronic blood loss
Renal impairment
Endocrine disorders
Anemia resulting from metastatic invasion of the bone marrow
Thalassemia minor
Dilution anemia
18. THERAPY AND PROGNOSIS
Anemia that presents in the setting of infection , inflammation , or
malignancy requires sufficient diagnostic studies to more
threatening causes , such as occult hemorrhage ; iron , B12 , and
folate deficency ; hemolysis and drug reaction .
If the anemia can be designated as AI after such studies ,effective
treatment of the underlying disease resolves the anemia