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CBC --- Interpretations Dr.Duaa Hiasat. In this hour we will review: Definition of anemia Signs and symptoms Cause Possible complication Utility of the CBC and reticulocyte count And give you a simple plan to:
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In this hour we will review: Definition of anemia Signs and symptoms Cause Possible complication Utility of the CBC and reticulocyte count And give you a simple plan to: Categorize anemias into 3 morphologic groups Develop a differential diagnosis Decide on further laboratory evaluation Quiz questions objectives
CBC- complete blood count • Component of the CBC: • Red Blood Cells (RBCs)• Hematocrit (Hct)• Hemoglobin (Hgb)• Mean Corpuscular Volume (MCV)• Mean Corpuscular Hemoglobin Concentration (MCHC) - Red cell distribution width (RDW) • White Blood Cells (WBCs)• Platelet
RBC • RBC (varies with altitude): • M: 4.7 to 6.1 x10^12 /L • F: 4.2 to 5.4 x10^12 /L • Biconcave disc shape with diameter • of about 8 µm • Function: - transport hemoglobin which carries oxygen from the lung to the tissues • -acid –base buffer. • Life span 100-120 days.
Hemoglobin & Hematocrit Hemoglobin : 1 week: 13-20 •1 month: 11-17 6months 10.5-14.5 •1 year: 10.5-15 10years: 11-16 •15years: 14-18M ; 12-16F Hematocrit : (packed cell volume) It is ratio of the volume of red cell to the volume of whole blood. 14-90d:35-49 6m-1yr:30-40 4-10yr: 31-43 Adult:42-52M; 37-47F
MCV&MCHC • MCV = mean corpuscular volume HCT/RBC count= 80-100fL • small = microcytic • normal = normocytic • large = macrocytic • MCHC= mean corpuscular hemoglobin concentration HB/RBC count= 26-34% • decreased = hypochromic • normal = normochromic
MCH & RDW • MCH (mean corpuscular hemoglobin) HB/HCT = 27-32 pg • RDW (red cell distribution width) • It is correlates with the degree of anisocytosis _ Normal range from 10-15%
The RULE of Three Applies to normocytic, normochromic erythrocytes only Useful to detect laboratory error in measuring the Hb, HCT, and RBC count 3 times the RBC count should = Hb 3 times Hb should = Hct
The Reticulocyte Count • This important value is needed in the evaluation of any anemia. • Normal range 1-2% Must correct for degree of anemia Observed retic count (Actual HCT ÷ Normal HCT) = Corrected retic count • Retic count goes up with • Hemolytic anemia • Retic goes down with • Nutritional deficiencies _ Diseases of the bone marrow itself
Definition of Anaemia Anemia is a level of Red cells, Hemoglobin, or Hematocrit that is below the lower limit of normal for age and sex. Anemia is not a disease, it is a sign of disease As such, critical for all practitioners to know how to evaluate / determine its cause / treat Mechanisms: Increased loss (external) - hemorrhage Increased destruction (internal) - hemolysis Decreased production (trouble in the bone marrow)
So What’s the Plan? Hx and examination CBC- define anemia Look at red cell indices Categorize the anemia based on RBC size Reticulocyte count - marrow response Note any RBC anisopoikilocytosis Consider the differential diagnosis Plan your laboratory evaluation
Symptoms • Can minor or vague • Weakness and fatigue • Poor concentration • Dyspnea on exertion • Palpitation and angina • Pica • Behavioral disturbances in children • Dizziness • intermittent claudication • Symptoms of heart failure • Impaired infant development • Reduced school performance
Clinical Signs to be looked for Pallor(skin,mucosal lining and nail beds) Koilonychia in IDA Jaundice in hemolytic anemia Bone deformities in thalassemia major Leg ulcers in sickle cell disease Signs of hyperdynamic circulation: Tachycardia Flow murmure Cardiac enlargement glossitis ,smooth red tongue
Causes of Anaemia Decreased production of Red Cells - Hypoproliferative, marrow failure Increased destruction of Red Cells - Hemolysis (decreased survival of RBC) Loss of Red Cells due to bleeding - Acute / chronic blood loss (hemorrhagic)
Anaemia Hb% < 12, Hct < 38% Hemolytic Hypoproliferative Retics < 2 Retics > 2
Workup – Second Test The next step is ‘What is the size of RBC’ ? MCV indicates the Red cell volume (size) Both the MCH & MCHC tell Hb content of RBC If the Retic count is 2 or less we are dealing with either Hypoproliferativeanaemia (lack of raw material) Maturation defect with less production Bone marrow suppression (primary/ secondary)
Mean Cell Volume (MCV) RBC volume is measured by The Mean Cell Volume and RDW MCV Microcytic Normocytic Macrocytic < 80 fl 80 -100 fl > 100 fl < 6.5 µ 6.5 - 9 µ > 9 µ
Anaemia Workup - MCV MCV Microcytic Normocytic Macrocytic Chronic disease Early IDA Hemoglobinopathies Primary marrow disorders Combined deficiencies Increased destruction Iron Deficiency IDA Chronic Infections Thalassemias Hemoglobinopathies Sideroblastic Anemia Megaloblastic anemias Liver disease/alcohol Hemoglobinopathies Metabolic disorders Marrow disorders
Red cell Distribution Width - RDW RDW Normal High Population Uniform Population Double
Anaemia Workup - 4th TestPeripheral Smear Study Are all RBC of the same size ? Are all RBC of the same normal discoid shape ? How is the colour (Hb content) saturation ? Are all the RBC of same colour/ multi coloured ? Are there any RBC inclusions ? Are leucocytes normal in number ? Is platelet distribution adequate ?
Causes of IDA • Inc. need : pregnancy. normal growth. • Dec. intake or absorption: nutrition gastric surgery celiac sprue • Inc. blood loss: GERD,PUD, gastritis IBD malignancy menstruation
IDA Summary Microcytic MCV < 80 fl, RBC < 6 µ RDW Widened with low MCV Hypochromic MCH < 27 pg, MCHC < 30% RI < 2 Serum ferritin Very low < 30 (p mols/L) TIBC Increased > 400 (µg/dL) Serum Iron Very low < 30 (µg/dL) BM Fe Stain Absent Fe Response to Fe Rx. Excellent
Treatment • Explore the cause and treat it • Nutrition such as: Chicken and turkey peas, and beans Eggs (yolk) Fish Meats (liver is the highest source) Peanut butter Soybeans Whole-grain bread apricots ,Spinach • Medical : Iron supplement. Take iron tablets on an empty stomach. Take iron tablets with vitamin C. Vitamin C improves the absorption of iron
IDA- Some Nuggets Look for occult blood loss Pica and Pagophagia – Ice sucking Food, Ca, Phosphate, antacids ↓absorption Ascorbic acid ↑absorption Oral iron Rx. always is the best, FeSO4 is the best. Reserve parenteral Rx. Packed cell transfusion in emergency Continue Fe Rx at least 2 months after normal Hb 1 gram ↑in Hb every week can be expected Always supplement protein for the Globin component
Thalassemia • It is forms of inherited autosomal recessiveblood disorders that originated in the Mediterranean region patients with thalassemiatraits do not require medical or follow-up care after the initial diagnosis is made. • Patients with β-thalassemia trait should be warned that their condition can be misdiagnosed for the common Iron deficiency anemia. • Counseling is indicated • Screening by CBC • Hb 10 MCV 65 RBC 5.9 • Mentzerindex:MCV/RBC >13 IDA <11.5 Thalassemia
Therapy for beta thalassemia primarily involves chelation or removal of excessive iron deposits in the blood • Curative methods Bone Marrow Transplant • Beta-thalassemia major requires lifelong blood transfusions. • Alpha-thalassemia major is also referred to as hydropsfetalis • Diagnosed by blood electrophoresis • Hb A2 >3.5 • Hb A <95Hb F >1
Complication • Iron overload • Infection: This is especially true if the spleen has been removed. • Bone deformities: Thalassemia can make the bone marrow expand, which causes bones to widen especially in the face and skull. • Enlarged spleen • Slowed growth rates:Puberty also may be delayed in children with thalassemia. • Heart problems: such as congestive heart failure and abnormal heart rhythms (arrhythmias), may be associated with severe thalassemia.
Macrocytic Anaemias MegaloblasticMacrocytic– B12 and Folate↓ (hypersegmentedneutrophil) B. Non MegaloblasticMacrocyticAnaemias Liver disease/alcohol Hemoglobinopathies Metabolic disorders, Hypothyroidism Myelodystrophy, BM infiltration Accelerated Erythropoesis -↑destruction Drugs (cytotoxics, immunosuppressants, anticonvulsants)
Anemia - Macrocytic (MCV > 100) Macrocyticanemias may be asymptomatic until the Hb is as low as 6 grams MCV 100-110 fl must look for other causes of macrocytosis almost always folate or B12 deficiency
Symptoms of MBA • memory loss, • depression, • personality changes, and psychosis • peripheral neuropathy. • ataxia, • become weak, • lose proprioceptive and vibratory senses. • If not treated, mental and neurological changes can become permanent. • in pregnant woman folate deficiency causes neural tube defect in the infant • numbness or tingling in hands and feet • smooth and tender tongue
Causes • digestive diseases celiac disease, chronic infectious enteritis, and enteroenteric fistula. lack of intrinsic factor in gastric (stomach) secretions. • malabsorptionInherited congenital folatemalabsorption, without detection cause mental retardation. • Medication-induced folic acid deficiencY that prevent seizures, such as phenytoin, primidone, and phenobarbital, • Foods that are rich in folic acid include the following:Oranges,Spinach, Liver, Rice, soy beans, green, leafy vegetables, Bean, peanuts • Foods that are rich in folic acid and vitamin B12 include the following:Eggs, Meat, Poultry, Milk, Shellfish Fortified cereals
TREATMENT • Must be tailoret to cause • Replacement : Folic acid : 1 mg /d Vit B12 : 1000 micrgr/d I.M for 5 days ,then q week until Hct normal, then q month for life .
Basophilic Stippling - MBA BS occurs in Lead poisoning also
Pernicious Anaemia - Tongue Bald, smooth, lemon yellowish red tongue
Normocytic Anaemias Chronic disease Early IDA Hemoglobinopathies Primary marrow disorders Combined deficiencies Increased destruction Frequent sampling -ICU
Anaemia of Chronic Disease Thyroid diseases Malignancy Collagen Vascular Disease Rheumatoid Arthritis SLE Polymyositis Polyarteritis Nodosa • IBD – Ulcerative Colitis – Crohn’s Disease • Chronic Infections – HIV, Osteomyelitis – Tuberculosis • Renal Failure
CBC in ACD • Anemia of chronic disease is often a mild normocytic anemia, show a low reticulocyte production index, suggesting that reticulocyte production is impaired and not enough to compensate for the decreased red blood cell count. • While no single test is always reliable to distinguish the two causes of disease, there are sometimes some suggestive data: • ferritin levels should be normal or high, reflecting the fact that iron is stored within cells, and ferritin is being produced as an acute phase reactant • TIBC should be low or normal in anemia of chronic disease
‘Dimorphic’ Anaemia Folate & Fe deficiency (pregnancy, alcoholism) B12 & Fe deficiency (PA with atrophic gastritis) Thalassemia minor & B12 or folate deficiency Fe deficiency & hemolysis (prosthetic valve) Folate deficiency & hemolysis (Hb SS disease) Peripheral smear exam is critical to assess these RDW is increased very much