Characteristics of Common Anemias
Etiology or Type | Morphologic Changes | Special Features |
|---|---|---|
Blood loss, acute | Normochromic-normocytic, with polychromatophilia | If severe, possible nucleated RBCs and left shift of the WBCs Leukocytosis Thrombocytosis |
Blood loss, chronic | Same as iron deficiency | Same as iron deficiency |
Same as vitamin B12 deficiency | Serum folate < 5 ng/mL (< 11 nmol/L) RBC folate < 225 ng/mL RBCs (< 510 nmol/L) Nutritional deficiency and malabsorption (in sprue, pregnancy, infancy, or alcohol use disorder) | |
Spheroidal microcytes Normoblastic erythroid hyperplasia Reticulocytosis | Increased MCHC Increased RBC osmotic fragility Shortened survival of labeled RBCs | |
Hemolysis | Normochromic-normocytic Reticulocytosis Marrow erythroid hyperplasia | Increased serum indirect bilirubin and LDH Increased stool and urine urobilinogen Hemoglobinuria in fulminating cases Hemosiderinuria |
Infection, cancer, or chronic inflammation | Normochromic-normocytic early, then microcytic Normoblastic marrow Normal or increased iron stores | Decreased serum iron Decreased total iron-binding capacity Normal serum ferritin Normal or increased marrow iron content |
Microcytic, with anisocytosis and poikilocytosis Reticulocytopenia Hyperplastic marrow, with delayed hemoglobination | Possible achlorhydria, smooth tongue, angular cheilosis, and spoon nails Absent stainable marrow iron Low serum iron Increased total iron-binding capacity Low serum ferritin | |
Marrow failure | Normochromic-normocytic (may be macrocytic) Reticulocytopenia Failed marrow aspiration (often) or evident hypoplasia of erythroid series or of all elements | Idiopathic (> |
Marrow replacement (myelophthisis) | Anisocytosis and poikilocytosis Nucleated RBCs Early granulocyte precursors Marrow aspiration possibly failing or showing leukemia, myeloma, myelofibrosis, or metastatic cells | Marrow infiltration with infectious granulomas, tumors, fibrosis, or lipid histiocytosis Possible hepatomegaly and splenomegaly Possible bone changes (osteosclerosis) |
Red cell agglutination Reticulocytosis | Follows exposure to cold Results from a cold agglutinin or hemolysin Sometimes postinfectious (paroxysmal cold hemoglobinuria) | |
Leukopenia Thrombocytopenia Reticulocytosis | Dark morning urine Hemosiderinuria Thrombosis | |
Anisocytosis and poikilocytosis Some sickle cells in peripheral smear Sickling of all RBCs in preparation with hypoxia or hyperosmolar exposure Reticulocytosis | Largely limited to people of African ancestry in the United States Urinary hyposthenuria Hb S detected during electrophoresis Possibly painful vaso-occlusive crises and leg ulcers Bone changes on x-ray | |
Usually hypochromic but dimorphic with normocytes and macrocytes Hyperplastic marrow, with delayed hemoglobination Ringed sideroblasts | Usually stainable marrow iron (plentiful), but can be reduced) Some congenital forms respond to vitamin B6 administration Can be part of a myelodysplastic syndrome | |
Microcytic Target cells Basophilic stippling Anisocytosis and poikilocytosis Nucleated RBCs in homozygotes Reticulocytosis | Elevated Hb A2and Hb F (in beta-thalassemia) Mediterranean ancestry (common) In homozygotes, anemia from infancy Splenomegaly Bone changes on x-ray | |
Oval macrocytes Anisocytosis Reticulocytopenia Hypersegmented WBCs Megaloblastic marrow | Serum B12 < 200 pg/mL (< 145 pmol/L) Frequent GI and CNS involvement Increased LDH Antibodies to intrinsic factor in serum (pernicious anemia) Sometimes absent gastric intrinsic factor secretion | |
CNS = central nervous system; GI = gastrointestinal; Hb = hemoglobin; LDH = lactic dehydrogenase; MCHC = mean corpuscular hemoglobin concentration; RBC = red blood cell; WBC = white blood cell. | ||