• Information
  1. Key Evaluations
  2. Microcytic
  3. Macrocytic
  4. Normocytic

A. Key Evaluations
[Figure] "Evaluation of Anemia"

1. Blood Smear - for abnormal cells, especially evidence of cell breakdown
2. Reticulocyte Count

B. Microcytic (mean corpuscular volume, MCV <84 fL)

1. Iron Deficiency
   1. Characterized by increased RDW, low MCV; Low Iron and Ferritin Levels; elevated TIBC
   2. Gastrointestinal bleeding: colon cancer, polyp, diverticuli, ulcer, others
   3. Epistaxis
   4. Hematuria
   5. Uterine Bleeding
   6. Bleeding Diathesis
2. Abnormal Hemoglobin
   1. Thalassemia (Target Cells)
   2. Sickle cells
   3. High oxygen hemoglobin mutants - cause polycythemia and iron deficiency [1]
3. Metabolic
   1. Glucose 6-P Dehydrogenase Deficiency
   2. Pyruvate Kinase Deficiency
4. Paroxysmal Nocturnal Hemoglobinuria (PNH)
5. Cryoglobulinemia
   1. Viral infection
   2. Mycoplasma infection
6. Anemia of Chronic Disease
   1. Inflammation is present and ESR / CRP is nearly always elevated
   2. Reticulocyte count reduced, Ferritin level elevated, Iron and TIBC both decreased
   3. Chronic infections
   4. Neoplasia
   5. Tissue Necrosis - including decubitus ulcer
   6. Collagen Vascular Disease
   7. Arthritis - Rheumatoid and other inflammatory arthritides
7. Burr Cell Anemias (Burr Cells on Smear)
   1. Liver Disease
   2. Renal Disease
   3. Shock with Acute Tubular Necrosis (ATN)

C. Macrocytic (MCV >105 fL)

1. B12 Deficiency - often with change in mental status, large platelets
2. Folate Deficiency
3. Folate Antagonists
   1. Trimethoprim, Sulfamethoxazole
   2. Dapsone
   3. Methotrexate
4. Zidovudine (AZT)
5. High Reticulocyte Count
   1. Subacute hemorrhage
   2. Hemolysis - intrinsic or extrinsic
6. Sideroblastic Anemia
7. Macrocytic and Hypochromic
   1. Isoniazid
   2. Cancer Chemotherapy
   3. Alcoholism
   4. Idiopathic
8. Fanconi's Anemia
9. Liver Disease
10. Myxedema (Hypothyroid)
11. Myelodysplastic Syndrome (MDS)

D. Normocytic

1. Normal Marrow
   1. Subacute Hemorrhage
   2. Chronic Infection
   3. Renal Failure - creatinine usually >3mg/dL; low erythropoietin, low reticulocyte count
   4. Endocrine Disease
   5. Liver Disease
   6. Malignancy
2. Abnormal Marrow
   1. Hypoplastic / Aplastic
   2. Leukemia
   3. Other Malignancy
3. Hemolytic - evidence on smear, elevated LDH, AST, Indirect Bilirubin and Reticulocytes
   1. Autoimmune (Coombs' Direct Antiglobin Test positive)
   2. Hemoglobinopathy: HbSS, HbSC
   3. Hereditary
   4. Spherocytosis, Ovalocytosis
4. Microangiopathic Thrombotic Thrombocytopenic Purpura (HUS / TTP) Disseminated Intravascular Coag (DIC)
5. Infection
6. Uremia

References

1. Pavic M, Francina A, Durand DV, Rousset H. 2003. Lancet. 362(9396):1624