Anemia of chronic disease

anemia of chronic disease
by amirhossein heydarian
hematologist

1. ANEMIA OF CHRONICH DISEASE By amirhossein heydarian

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

5. ETIOLOGY Autoimmune Rheumatoid arthritis and other rheumatologic disorders Systemic lupus erythematosus and connective-tissue diseases Vasculitis Sarcoidosis Inflammatory bowel disease systemic inflammatory response syndrome

6. ETIOLOGY Chronic rejection after solid-organ transplantation Chronic kidney disease and inflammation

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. LABORATORY FEATURES 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. 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 )

11. Increased serum ferritin Serum ferritin concentrations , which reflects iron stores , are increased in AI but decreased in Iron deficiency .

12. 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.

13. 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

14. Algorithm for the Differential Diagnosis

15. 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

16. Therapeutic Options for ACD