内科学 贫血总论 PPT课件

A. Clinical findings
1. Clinical signs 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
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 female(adult)<110g/L female(gestation)<100g/L
Red cell count male<4.5x1012 /L female<4.0x1012 /L
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. Hb and RBC may be used to
further classify the anemia.
II. Classification
A. Size (MCV) and Hb Concentration (MCHC) 1. Normocytic, macrocytic, microcytic. 2. Normochromic, hypochromic. (Hyperchromia does not occur)
a. Complement-mediated lysis. (neonatal isoerythrolysis and transfusion reactions, PNH )
b. Physical injury(Traumatic ,microangiopathic anemia, DIC,Coagulation,Vasculitis)
c. Hemoglobinemia and hemoglobinuria are absent.
d. Hyperbilirubinemia e. Neutrophilia, monocytosis, and thrombocytosis f. Splenomegaly.
h. Low-grade extravascular hemolysis occurs in many anemias that are primarily nonhemolytic (e.g., anemia of chronic renal disease,irondeficiency anemia). Referred to as the “hemolytic component” of other types of anemia
1.Blood loss–hemorrhagic anemia.
2. Accelerated erythrocyte destruction–hemolytic anemia.
3. Reduced or defective erythropoiesis
ANEMIA FROM ACCELERATED ERYTHROCYTE DESTRUCTION (HEMOLYTIC ANEMIA)
.
2. Non-Regenerative a. Inadequate bone marrow response
because of a bone marrow disorder. b. Polychromasia and reticulocytosis
are absent. •
C. Pathophysiologic mechanism
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.
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
b. Decreased erythrocyte deformability (a)Shistocytes of microangiopathic anemia
(b) Spherocytes of immune-mediated anemia (c) Parasitized erythrocytes (d) Heinz body-containing cells
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).
B. Intravascular hemolysis– Erythrocytes are destroyed within the circulation,
releasing hemoglobin into the plasma where it is either removed by the liver or excreted by the kidneys.
anemia associated cardiac disease: Hb<30g/L more than 2 months heart enlargement ST depression
d. headache,dizziness e.anorexia,nauxea,abdominal fullness
B. Laboratory findings
1. Reticulocyte counts are higher in hemolytic anemias than external hemorrhagic anemias 2. Plasma protein concentration is normal or increased.
1. The Hct is the easiest, most accurate method for detecting anemia. Its result should be interpreted with knowledge of the hydration status and any alteration caused by splenic contraction.
diarria or constipation, Icterus. f.menstruation disorder or amenorrea hemoglobinuria g. Shock if >1/ 2blood volume lost in short period.
C. Laboratory findings
<32
iron deficiency anemia sideroblastic anemia thalassemia
B. Bone marrow response 1. Regenerative a. Bone marrow actively responds by increasing its production of RBC’s. 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 in MCV and RDW
c. Reduced glycolysis and ATP content of the erythrocyte( PK deficiency) d. Increased macrophage activity
(hyperscular causes of hemolysis do not lyse all erythrocytes; some altered cells may remain that are removed by phagocytosis.