ANEMIA is a decrease in number of red blood cells(RBCs) or less than the normal quantity of hemoglobin in the blood. The normal range varies with age, so anaemia can be defined as: Neonate: Hb <14g/dl 1-12 months: Hb <10g/dl 1-12 years: Hb <11g/dl. ˃12years: <12g/dl Hb Anemia is not a disease, but an expression of an underlying disorder or disease.
ETIOLOGIES Production defects: Nutritional deficiencies - Vitamin B12, folate or iron deficiency. Inflammation/chronic disease. bone marrow disorders- pure red cell aplasia,myelodysplasia. Blood loss Hemorrhage Chronic GI blood loss Blood destruction. haemolysis Sequestration (hypersplenism)-usually associated with mild pancytopenia
ASSESSMENT diagnosis is made by: Patient history Patient physical exam Hematologic lab findings Identification of the cause of anemia is important so that appropriate therapy is used to treat the anemia.
Patient History Dietary habits Medication Possible exposure to chemicals and/or toxins Description and duration of symptoms Tiredness Headache and vertigo (dizziness) Dyspnia from exertion G I problems Overt signs of blood loss such as hematuria (blood in urine) or black stools
Patients with acute and severe anemia appear in distress, with tachycardia, tachypnea, and hypovolemia. Patients with chronic anemia are typically well compensated and usually asymptomatic
Hematologic Lab Findings Hematocrit (Hct) or packed cell volume in % The normal range is 42-60% Hemoglobin (Hgb) concentration in grams/deciliter The normal range is 13.5-20 g/dl An RBC count: The normal range is 13.5-20 g/dl Reticulocyts : The normal range is 0.5% to 1.5%
Mean corpuscular volume (MCV) Hct (in %)/RBC (x 1012/L) x 10 At birth the normal range is 98-123 In old child and adults the normal range is 80-100 The MCV is used to classify RBCs as: Normocytic (80-100) Microcytic (<80) Macrocytic (>100)
Mean corpuscular hemoglobin concentration (MCHC) – is the average concentration of hemoglobin in g/dl (or %) Hgb (in g/dl)/Hct (in %) x 100 The normal range is 30-36 The MCHC is used to classify RBCs as: Normochromic (30-36) Hypochromic (<31) hyperchromic, not (>37), they just have decreased amount of membrane.
Mean corpuscular hemoglobin (MCH) – is the average weight of hemoglobin/cell in picograms (pg= 10-12 g) Hgb (in g/dl)/RBC(x 1012/L) x 10 At birth the normal range is 31-37 In adults the normal range is 26-34 This is not used much anymore because it does not take into account the size of the cell.
Red cell distribution width (RDW) – is a measurement of the variation in RBC cell size Standard deviation/mean MCV x 100 The range for normal values is 11.5-14.5% A value > 14.5 means that there is increased variation in cell size above the normal amount A value < 11.5 means that the RBC population is more uniform in size than normal.
Using MCV to Characterize Anemia Microcytic Normocytic Macrocytic Iron deficiency Acute blood loss Normal newborn anemia Infection Increased Thalassemia erythropoiesis Renal failure Post-splenectomy Sideroblastic anemia Liver disease Liver disease Chronic infection Early iron Obstructive Severe Malnutrition deficiency jaundice Hypothyroidism
Managment Acute anemia usually warrants immediate medical attention. Treatment depends on the severity and underlying cause of the anemia Supportive measures, such as supplemental oxygen for decreased oxygen-carrying capacity, fluid resuscitation for hypovolemia, and bed rest or activity restriction for fatigue, may be required
When to transfuse? PRBC dose is 15-20 ml/kg over 3-4 hours. the rate oftransfusion can be modified according to the clinical situation. Give PRBCs if: Hb˂5g/dl Hb ≤7 g/dl with regardless of clinical signs of clinical signs of anemia anemia
Iron Deficiency Anemia Dx: Smear: microcytic & hypochromic additional diagnostic tests serum ferritin (decreased) serum iron (decreased) Iron binding capacity (increased) Iron saturation (decreased)
Tx: oral iron supplementation: 6mg/kg/day of elemental iron for at least 3 months check retic count after 2 weeks Iron Dextran provides 50mg/ml elemental iron Dose(ml) =0.0442 (desired Hgb - Observed Hgb) x Wt + (0.26 x W) Ferrlecit (sodium ferrous gluconate) each 10cc provides 125mg elemental iron dilute 10ml in 100ml 0.9NS and administer IV over 1 hour repeat for up to 8 sessions
B12/Folate Deficiency Dx: Smear: Macrocytic (High MCV) RBCs, B12 Low serum B12, Anti-IF Abs, Folate Serum folate level-- can normalize with a single good meal Tx: B12 deficiency: B12 1 mg/month IM, or 1-2 mg/day PO Folate deficiency: Improved diet, folate 1 mg/day
Thalassemias Genetic defect in hemoglobin synthesis synthesis of one of the 2 globin chains ( or ) “Ineffective erythropoiesis” Dx: Smear: microcytic/hypochromic, RBCs Fe stores are usually elevated Tx: Mild: None Severe: RBC transfusions + Fe chelation, Stem cell transplants
Prognosis The prognosis depends on the severity and acuteness with which the anemia develops and the underlying cause of the anemia. Mortality and morbidity rates vary according to the underlying pathologic process causing the anemia, the degree of severity, and the acuteness of the process.
CONCLUSION Anemia is not a desease but, a condition caused by various underlying pathologic processes A proper history and physical examination is more important in an easy way of approaching a child with anemia Lab exams leads to definitive cause of anemia All cases of anemia are not necessary to be transfused
REFERENCES Illustrated textbook of paediatrics 3rd edition, Tom Lissauer and Graham Clayden, 2010 First aid for Pediatric clerkship, LATHA G. STEAD et al Pocket medicine 4th edition, Mare S. Sabatine, 2011 Emedicine.medscape.com/article/954506 Pedinreview.com