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Dr Heersh HMH Raof Saeed. Hematology (lecture 1). Introduction : Blood is essential for maintenance of life. Component : Plasma. Blood cells Hb . level varies from one age to another. 55% at birth 30% by 2-3 months
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Dr Heersh HMH RaofSaeed Hematology (lecture 1)
Introduction:Blood is essential for maintenance of life • Component : • Plasma. • Blood cells • Hb. level varies from one age to another. • 55% at birth • 30% by 2-3 months • 35% at 1 year • 40% at 3 years • 45% at 15 years
Introduction: cont. • R.B.C. • 5.5 millions/ c.mm at birth • 4.5 millions/ c.mm at 1 year • 5 millions/ c.mm at 15 years • W.B.C. • 22000 cells / c.mm at birth • 12000 cells / c.mm at 1 week – 1 year • 8000 cells / c.mm at 4 years • Life span: • R.B.C: 120 days • W.B.C: 5-10 days • Platelets: 10 days Blood volume: 85ml/ kg at birth 75-80ml/kg from 2nd month
Anemias: • Definition: abnormally low R.B.C., Hb, or P.C.V. • Aetiology: I_ Decreased or impaired production: A. Substrate deficiency B. Depression of bone marrow: 1. Hypoplastic anemia: a. congenital; pure red cell anemia , Fanconi anemia b. Acquired 2. Bone marrow replacement II_ Blood loss: III_ Excessive R.C. destruction ( hemolysis )
Anemias: • Physiologic adjustments to anemia include: • cardiac output, • oxygen ex traction • shunting of blood • the concentration of 2,3-diphosphoglycerate (2,3-DPG) increases within the RBC. • “ shift to the right” • erythropoietin (EPO)
Anemias: • History and Physical Examination • HISTORY: Important historical facts should include: • age, sex , race and ethnicity , diet, • medications, chronic diseases, infections, • travel, • A family history of anemia and/or • associated difficulties such as splenomegaly , jaundice, or early-age onset of gallstones is • EXAMINATION: • pallor , • sleepiness, • irritability , and decreased exercise tolerance. • flow murmur is often present. • weakness, tachypnea, shortness of breath on • exertion, tachycardia, cardiac dilatation, and high-output heart failure
Anemias: • Laboratory Studies • Initial laboratory testing should include • hemoglobin, • hematocrit, • red cell indices • white blood cell count and differential, • platelet count, reticulocyte count, and examination of the peripheral blood smear . • additional laboratory studies is dictated by the history , the physical, and the results of this initial testing
Iron deficiency anemia: • Iron metabolism: • newborn contains _________0.5 gm of iron • adult contains __________5 gmof iron (full term infant requires 0.8mg daily .) • In the first half of infancy, iron reserves, • After 6 months of age, diet. • As only 10% of dietary iron is absorbed • Iron is transported in the plasma (ferric state) combined with transferrin’’ , by which way iron can be delivered to the bone marrow , spleen & liver for storage or erythropoiesis • Iron is absorbed in the duodenum (ferrous state) oxidized iron + apoferritinferiitin (anemia reduces ferric state increase apofritin)
Iron deficiency anemia: • Aetiology :(most commonly between 6 & 24 months) • 1. Inadequate supply of iron; • Inadequate stores of iron at birth: • B- Inadequate intake of iron. 2. Impaired iron absorption: 3. Increased demand for iron: A- Blood loss: B- increased demands for growth:
Iron deficiency anemia: • Clinical feature : • Symptoms: • Pallor : g/dl) • Lethargy • irritablitty • anorexia • fatigue after physical activity • Pica (plumbism) • Signs: • Pallor • Mild splnomegaly in 20-30% • Fragile nails .koilonychias • Tachypnea ,functional murmur &rarely C.H.F in very sever cases • Atrophic glossitis & dysphagia.
Iron deficiency anemia: • Laboratory investigations: • Hypochromic ,microcytic anemia with poikilocytosis & target cell in the blood smear. • Decreased PCV. • Decreased Hb concentration. • Slight reduction of R.B.C count. • Decreased MCV. • Decreased MCHC. • Decreased MCH. • Normal W.B.C, platelet & reticulocytes. • Decreased S. ferritin to less than 10 microgm/lit. • Decreased S. iron. • Increased total iron binding capacity ( transferrin ) , with iron saturation less than 16% . • Bone marrow examination is rarely required, when performed; it shows erythroid hyperplasia with predominance of normoblasts. Hemosiderosin is totally absent.
Differential diagnosis: 1. Thalassaemia minor 2. Anemia of chronic infection. 3. Lead poisoning ; basophilic stippling of the R.C. together with elevated blood & urine lead levels are characteristic of lead poisoning 4. Pyridoxine deficiency. 5. Sideroblastic anemia.
Iron deficiency anemia: • Treatment: (The regular response of iron-deficiency anemia to adequate amounts of iron is a critical diagnostic and therapeutic feature ) • Iron is available in the form of drops, syrup, tablets & injections. • is 6 mg/kg/day (Vit. C ) …….. oral therapy (4-6 weeks after Hb values is normal ) • Parenteral iron : 1. Poor iron absorption 2. When its difficult to compensate continuous iron loss as in hereditary telengeictasia. 3. Intolerance of oral iron. 4. Non-compliance of giving or taking iron
Iron deficiency anemia: • Blood transfusion is rarely indicated, in extremely severe cases • heart failure is about to occur, • correction of severe anemia prior to a necessary operation. • Partial correction, in these situations,, is preferable.
Iron deficiency anemia: • Prevention: • Breastfeeding should be encouraged, with the addition of iron-fortified cereals after 4-6 m o of age • 1mg/kg/day should be supplied from 3 months of age • I nfantswhoare not breast-fed should only receive iron-fortified formula (12 mg of iron per liter) for the first year
Iron deficiency anemia: • Causes of failure to respond to oral iron: 1- Wrong diagnosis. 2- Non- compliance. 3- Persistent hemorrhage. 4- Impaired bone-marrow response as in presence of chronic infections, renal failure, or when B12 & folic acid deficiency co-exists. 5- Impaired absorption. 6- Unknown cause. routine screening helps prevent the development of severe anemia. Routine screening using hemoglobin or hematocrit is done at 12 m o of age, or earlier if at 4 m of age the child is assessed to be at high risk for iron deficiency
Sideroblastic anemia • Definition:Sideroblasticanemiasresult from acquired and hereditary disorders of hem e synthesis. • dimorphic population of erythrocytes • complete blood cell count indicates an extremely high RBC distribution width (RDW) • impaired hemesynthesis leads to retention of iron within the • mitochondria. (aggregates of iron in mitochondria) that have a perinuclear distribution. (sideroblasts) • Hepato-splenomegaly may be present.
Sideroblastic anemia • Treatment: • blood transfusions, • iron chelating agents • splenectomy may help