Definition A reduction below normal in the concentration of hemoglobin, the mass of red blood cells and/or the hematocrit in the blood. In men Hb < 120g/L RBC <4.5×10 12 /L HCT <0.42 In women Hb < 110g/L RBC<4.0 ×10 12 /L HCT<0.37
Factors influencing Hb concentration Sex Age Altitude Alterations in plasma volume
Kinetic classification (Classified according to etiology and pathogenesis) 一、 Decreased erythropoiesis 1Proliferation and differentiation abnormalities of SC HSC: AA, Fanconis anemia, MDS Erythrocytic progenitors : Pure red cell aplasia, Anemias caused by kidney failure and endocrine disorders
3Production and maturation blockages of differentiating cells DNA synthesis blockage : Vit B12, falic acid difficiencies, 嘌呤和嘧啶 metabolic defects→Megaloblastic anemia Hb synthesis blockage : Heme production defect : IDA Heptoglobin production defect : Thalassemias
Classified accordind to the proliferative situations of BM Hyperplastic anemias ( 增生性贫血 ): Hemolytic anemia Anemia caused by blood loss Megaloblastic anemia, IDA Hypoplastic anemias ( 增生减低性贫血 ): AA
Clinical manifestations Factors influencing symptoms: Severity of anemia Hb<80~90g/L→symptoms Rapidity of anemia Abrupt loss of 20% of the circulating blood volume → marked pallor, postural hypotension and tachycardia ( 心动过速 ) The loss of 50% → severe shock even dealth.
In contrast, the gradual loss (even Hb 30~40g/L) of the circulating red cell mass in a patient with pernicious anemia may occur without any symptoms at all.
Why? Red cell 2, 3 DPG (RBC 内 2, 3- 二磷酸甘油酸） ↑ In anemia the oxyhemoglobin dissociation curve usually shifts ( 右移 ) in a manner to increase the quantity of oxygen released in tissues without oppeciably altering the quantity of osygen bound in the lungs. Red cell 2,3 diphophoglycerate (2,3 DPG) regularly increases in anemic patients to mediate this effect. Maximum elevation of RBC 2,3 DPG increases oxygen delivery only about 30 per cent, but this is a highly efficient form of compensation requiring no significant expenditure of energy.
The aged patients or patients with vascular or cardiac diseases may not stand to milder anemia.
The level of anemia at which symptoms occur is highly variable among individuals as would be expected from the widely differing degrees of physical activity, physical conditioning, circulatory adequacy, and sensitivity or stoicism of the population.
１． General manifestations: ( Nonspecific and reflect tissue hypoxia) Tiredness, fatigue→ the most common, the earliest symptom Pallor of skin and mucosa→shared chracteristic ２． Cardiovascular systems : Palpitations and dyspnea on exertion, breathlessness→common symptoms Valvulae murmurs Hb 3m→Anemic cardic disease
The process of correct diagnosis is the one of differential diagnosis. Steps: 1. To Establish the type of anemia 2. To find out the cause or underlying diseases of anemia Diagnosis
1.Cause or inducer of anemia: Nutrition, special habits for food change in stool habits: stool Guaiacs in all profession influation of surrounding environment chronic diseases menstruation, marriage 一． History
2. Developing processes, severity & complications of anemias Duration and onset of symptoms 3.Important laboratory results, diagnosis, treatments and their effects.
skin and mucosa: pallor, jaundice, petechiae hair and nails adenopathy ( 淋巴结肿大 ) hepatomegaly-splenomegaly neurologic abnormalities 肛门及妇科盆腔检查 二． Physical examination
１、 The hemogram （血像） Routine blood exam(Hb,RBC) The reticulocyte count (RC) RC↑:hyperplastic RC↓:hypoplastic 三、 Laboratory findings
Reticulocyte Count Normal: Is required in the evaluation of all patients with anemia as it is a simple measure of production Young RBC that still contains a small amount of RNA Normally take 1 day for reticulocyte to mature. Under influence of epo takes 2-3 days 1/120 th of RBC normally
Absolute Retic count Retic counts are reported as a percentage: RBC count x Retic % = Absoulte retic count normal: (77+23) x 10 9 /L Absolute Retic counts need to be corrected for early release ( If polychromasia is present) Absolute retic/2 (for hct in mid 20’s) Absolute retic/3 (hct <20)
MCV(the mean corpuscular volume): the most useful of the RBC indices. MCH,MCHC: are rarely as helpful as the MCV The leukocyte and platelet count: Anemia with a diminished leukocyteand platelet count-pancytopenia- suggests either primary marrow disease, megaloblastic anemia, or hypersplenism. Examination of the peripheral blood smear:
2. Examination of bone marrow 骨髓涂片检查：主要观察 BM 增生程度，各系统细胞分类计 数，异常细胞，正常 BM 组织有核细胞与脂肪组织各占 1/2 ，前者增多（尤其是红系）见于增生性贫血，后者增 多代表 BM 增生低下，见于 AA ，骨髓小粒是血液稀释与 否的一个重要标志。 Examination of aspirated smears in general gives superior cytologic information while the core biopsy provides crucial information concerning the overall cellularity, as well as the presence of fibrosis, tumor, or granulomas. Both procedures are complemantary and are best performed together when the diagnosis is in doubt. Bone marrow iron staining
3. Some useful ancillary tests 1) Stools for occult blood 2) Tests for hemolytic anemia such as Coombs’test 3) Tests for nutritional anemia such as serum folic acid, serum Vitamin B12, SI, SF, etc. 4) Liver and kidney function tests 5) Immunologic tests 6) 影像学检查：钡餐透视，钡灌肠
Treatment 一、 Treatment of the causes The purpose is the treatment of the underlying disease. Gastric cancer→Pernicious anemia （恶性贫血） （ megaloblastic anemia ）
二、 Drugs 明确病因之前且忌乱投药 Iron agents; calculation of dose falic acid, Vit B 12 Vit B 6 Corticosteroids : AIHA ， AA, PNH Androgens: may promate reythropoiesis: 1.) 刺激 EPO 分泌。 2 ）增强 BM 对 EPO 的效应。 EPO: Anemia caused by kidney diseases Immunosuppression agents ALG (antilymphocyte globulin ） CsA: Acute and severe AA
三、 Transfusions Avoid of complications as hepatitis and AIDS Whole blood Frozed red cells Washed red cells Leukocyte poor packed cells （浓缩 RBC ） Chronic anemia : Hb<60g/L→Transfusion