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1、ANEMIA,Hematology Department,Huashan Hospital,Fudan University,Shanghai XieYan-Hui,DIAGNOSIS AND CLASSIFICATION Anemia is an absolute decrease in hematocrit , hemoglobin concentration, or the RBC count. Anemia is not a diagnosis, but a sign of underlying disease.,Hemoglobin(Hb): male(adult)120g/L fe
2、male(adult)110g/L female(gestation)100g/L Red cell count male4.5x1012 /L female4.0 x1012 /L Hemocrit(HCT) male0.42 female0.37 female(gestation)0.30,Determination of the cause:A. History1. Drug administration.2. Exposure to toxic chemicals 3. Family occurrence.4. Recent transfusions 5.menstruation(wo
3、man)6.ingestion(child)7.chronic disease8. Age at onset.,B. Physical findings and complaintsa. Pale mucous membranes and skinsb. Weakness, loss of stamina, and exercise intolerance,Hypersensitivity to cold ,fever. c. Tachycardia and polypnea,Heart murmur. anemia associated cardiac disease: Hb30g/L mo
4、re than 2 months heart enlargement ST depression,d. headache,dizzinesse.anorexia,nauxea,abdominal fullness diarria or constipation, Icterus.f.menstruation disorder or amenorrea hemoglobinuria g. Shock if 1/ 2blood volume lost in short period.,C. Laboratory findings1. The Hct is the easiest, most acc
5、urate method for detecting anemia. Its result should be interpreted with knowledge of the hydration status and any alteration caused by splenic contraction.,2. Hb and RBC may be used to further classify the anemia.,II. ClassificationA. Size (MCV) and Hb Concentration (MCHC)1. Normocytic, macrocytic,
6、 microcytic.2. Normochromic, hypochromic. (Hyperchromia does not occur),Type MCV(fl) MCHC(%) MCH(pg) disorder Macro 100 32 32-35 megaloblastic anemia MDS Normo 80-100 26-32 32-35 aplastic anemia,blood lost, hemolytic anemia Micro 80 26 32 iron deficiency anemia sideroblastic anemia thalassemia,B. Bo
7、ne marrow response1. Regenerativea. Bone marrow actively responds by increasing its production of RBCs.b. Findings:(1) Polychromasia.(2) Reticulocytosis,.(3) Macrocytosis (increased MCV) and hypochromia associated with reticulocytosis.(4) Hypercellular bone marrow with a low M/E ratio.(5) Increase i
8、n MCV and RDW,c. The presence of regeneration suggests an extramarrow cause. (1) Blood loss (2) Erythrocyte destruction (hemolysis) d. Bone marrow examination would reveal erythropoietic hyperplasia .,2. Non-Regenerative a. Inadequate bone marrow response because of a bone marrow disorder. b. Polych
9、romasia and reticulocytosis are absent.,C. Pathophysiologic mechanism Blood losshemorrhagic anemia. 2. Accelerated erythrocyte destructionhemolytic anemia. 3. Reduced or defective erythropoiesis,ANEMIA FROM ACCELERATED ERYTHROCYTE DESTRUCTION (HEMOLYTIC ANEMIA),A. Clinical findings 1. Clinical signs
10、 of hemorrhage are absent. 2. Jaundice may be seen in acute and severe cases. 3. Hemoglobinuria and red plasma is seen if significant intravascular hemolysis occurs,B. Laboratory findings 1. Reticulocyte counts are higher in hemolytic anemias than external hemorrhagic anemias 2. Plasma protein conce
11、ntration is normal or increased.,3. Neutrophilic leukocytosis and monocytosis may occur. 4. Evidence of Hb degradation (hyperbilirubinemia, hemoglobinuria). 5. Abnormal erythrocyte morphology (Heinz bodies, erythrocytic parasites,spherocytes, or poikilocytes).,I. Differentiation of the Causes of Hem
12、olytic Anemias A. Extravascular hemolysis,1. Mechanisms Autoimmune Mediated-Antibody and/or C3 mediated ( AIHA, infection, drug,immune system disorder) b. Decreased erythrocyte deformability (a)Shistocytes of microangiopathic anemia (b) Spherocytes of immune-mediated anemia (c) Parasitized erythrocy
13、tes (d) Heinz body-containing cells,c. Reduced glycolysis and ATP content of the erythrocyte( PK deficiency) d. Increased macrophage activity (hypersplenism),e. Intravascular causes of hemolysis do not lyse all erythrocytes; some altered cells may remain that are removed by phagocytosis.,2. Clinical
14、 and laboratory characteristics of phagocytic (extravascular) hemolysis. Usually chronic with insidious onset. b. A regenerative response. c. Hemoglobinemia and hemoglobinuria are absent.,d. Hyperbilirubinemia e. Neutrophilia, monocytosis, and thrombocytosis f. Splenomegaly.,h. Low-grade extravascul
15、ar hemolysis occurs in many anemias that are primarily nonhemolytic (e.g., anemia of chronic renal disease,iron-deficiency anemia). Referred to as the “hemolytic component” of other types of anemia,B. Intravascular hemolysisErythrocytes are destroyed within the circulation, releasing hemoglobin into
16、 the plasma where it is either removed by the liver or excreted by the kidneys.,1. Mechanisms: The erythrocyte membrane must be significantly disrupted to allow escape of the Hb molecule into the plasma. Most of the mechanisms of intravascular hemolysis are extrinsic or extracorpuscular defects the erythrocyte is initially normal.,Complement-mediated lys
