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186 Cards in this Set
- Front
- Back
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How big is a normal red blood cell?
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7.5-8.5 microns
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What is the normal percentage of reticulocytes in the blood?
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.5-1.5%
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If the patient has a low hematocrit, would you expect the person to make more or less retics?
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More
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What does a reticulocyte index less than 2 mean?
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Inadequate bone marrow response to degree of anemia
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What does a reticulocyte index of more than 3 mean?
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Appropriate bone marrow response to degree of anemia
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If reticulocytosis is seen with a reticulocyte index of more than 3, what is the DDx?
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Acute blood loss
Hemolytic anemia Response to Fe, folate, or B12 therapy |
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What is the role of B12 in the formation of an RBC?
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Essential for normal nuclear maturation and DNA synthesis
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Where is B12 obtained?
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Diet only
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What is necessary for B12 to be absorbed?
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intrinsic factor - 70% absorbed
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Where is intrinsic factor found?
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Terminal ileum
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What are the daily requirements for B12?
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2-5 micrograms
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Folic acid is essential to the synthesis of what?
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Nuclear proteins
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What food contains folic acid?
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Green leafy vegetables
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Where is folic acid absorbed?
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Proximal jejunum
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What is the daily requirement for intake of folic acid?
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50 micrograms
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What percentage of iron is absorbed daily?
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5-10%
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How much iron is gained and lost daily?
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1 mg loss
1 mg gain |
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Where is iron absorbed?
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Duodenum
Upper jejunum |
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How many milligrams of iron does an average adult have in their body?
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2475 mg
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How much iron does each gram of Hgb contain?
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3.3 mg
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What is the normal percentage of Hgb A in an adult?
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95%
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What is the normal percentage of Hgb A1c in an adult?
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3%
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What is the normal percentage of Hgb A2 in an adult?
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2%
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What is the normal percentage of Hgb F in an adult?
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Less than 1%
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What is globin broken down to?
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Amino acids
Reused in protein synthesis |
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What is heme broken down to?
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Bilirubin
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What is Hgb made of?
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Iron
Protoporphyrin Globin |
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Anemia of chronic disease is what kind of anemia?
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Microcytic
Hypochromic |
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Iron deficiency anemia is what kind of anemia?
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Microcytic
Hypochromic |
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Lead poisoning is what type of anemia?
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Microcytic
Hypochromic |
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Sideroblastic anemia is what type of anemia?
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Microcytic
Hypochromic |
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Thalassemia is what type of anemia?
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Microcytic
Hypochromic |
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What will the RDW be in a patient with iron deficiency anemia?
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High
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What will the transferrin be in a patient with iron deficiency anemia?
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High
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What will the iron saturation percentage be in a patient with iron deficiency anemia?
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Decreased
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What will the retic count be in a patient with iron deficiency anemia?
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Low retic count for degree of anemia
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What will the level of platelets be in a patient with iron deficiency anemia?
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Increased
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What are the causes of iron deficiency anemia?
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Blood loss
Increased demand for iron Malabsorption |
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What is the primary mechanism of anemia of chronic disease?
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Decreased RBC production
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What factors suppress RBC production in anemia of chronic disease?
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TNF
IL-1 |
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What substance from macrophages binds iron better than transferrin, preventing iron from making RBCs?
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Lactoferrin
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What type of anemia is anemia of chronic disease?
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Normocytic, normochromic
Progresses to microcytic, hypochromic |
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What will the serum iron and transferrin be in a patient with anemia of chronic disease?
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Decreased
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What will the ferritin be in a patient with anemia of chronic disease?
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Increased
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What is the usual Hgb in a patient with anemia of chronic disease?
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8-10
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What is the treatment for anemia of chronic disease?
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Treat underlying cause
Erythropoietin |
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Lead interferes with synthesis of what?
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Porphyrin
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Lead depresses what enzymes?
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ALA dehydratase
Heme synthetase |
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What would you find in a urinalysis of a patient with lead poisoning?
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Increased urine ALA levels
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What is the best test for diagnosis of lead poisoning?
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Increased free erythrocyte protoporphyrin
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What would you see on a blood smear of a patient with lead poisoning?
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Microcytic, hypochromic anemia
Basophilic stippling |
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Sideroblastic anemia is a defect in what?
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Mitochondria
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The defect in sideroblastic anemia prevents what?
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Incorporation of iron into Hgb
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What would you see in a blood smear of sideroblastic anemia?
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Ringed sideroblast from iron accumulation
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What is the hereditary etiology of sideroblastic anemia?
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X-linked recessive trait
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What is the acquired etiology of sideroblastic anemia?
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Drugs: ETOH, INH, chloramphenicol
Lead |
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Sideroblastic anemia is often the earliest evidence of what?
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Myelodysplastic syndrome
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What tests would be elevated in sideroblastic anemia?
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Serum LDH (ineffective erythropoiesis)
Transferrin saturation |
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Defects in thalassemia are what?
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Quantitative
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What is the result of thalassemia as it relates to hemoglobin?
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Abnormal amounts of structurally normal Hgbs
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Where is beta thalassemia usually seen?
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Mediterranean
Parts of Africa, Asia, South Pacific, India |
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Where is alpha thalassemia usually seen?
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Southeast Asia
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Beta thalassemia is a problem with what chromosome?
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Chromosome 11
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Beta thalassemia is a problem with what as it relates to chains?
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Decreased production of beta chains
Alpha chains in excess |
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What Hgbs are increased in beta thalassemia?
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Hgb A2
F Hgb Barts may also form |
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What is the problem with beta chains in beta thalassemia major?
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No beta chains or very little is made
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What is the problem with beta chains in beta thalassemia minor?
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Beta chains made in mildly reduced amounts
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What is the problem with beta chains in beta thalassemia intermediate?
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Beta chains made in amounts intermediate to the major and minor forms
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Beta thalassemia major is homozygous or heterozygous?
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Homozygous
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What is formed by the accumulation of excess alpha chains in beta thalassemia major?
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Heinz bodies in RBCs
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What would you see on a blood smear in a patient with beta thalassemia major?
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Nucleated red blood cells
Target cells High retics |
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What is the lifespan of patients with beta thalassemia major?
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Death usually occurs before age 20
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What does FE overload cause in beta thalassemia major patients?
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Heart failure
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What does beta thalassemia major cause in the growth of a patient?
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Growth retardation
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Beta thalassemia minor is heterozygous or homozygous?
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Heterozygous
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What would you see on the blood smear of a patient with beta thalassemia minor?
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Basophilic stippling
Target cells |
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What Hgb will be increased in beta thalassemia minor?
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Hgb A2
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If both parents have the beta thalassemia trait, what are the chances the offspring will have it?
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25% normal
50% trait only 25% with major beta thalassemia |
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Alpha thalassemia is a problem with what chromosome?
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Chromosome 16
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If all 4 genes are absent in alpha thalassemia, what usually occurs?
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Death in utero
Hydrops fetalis |
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If 3 genes are absent in alpha thalassemia, what occurs?
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Hgb H disease
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What are the findings in a patient with Hgb H disease?
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Moderate hemolytic anemia
Heinz bodies Microcytic, hypochromic Target cells |
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If 2 genes are absent in alpha thalassemia, what occurs?
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No clinical problem
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What are the laboratory findings in a patient with alpha thalassemia, with the absence of 2 genes?
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Microcytic, hypochromic RBCs
Hgb A2 normal |
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If 1 gene is absent in alpha thalassemia, what occurs?
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Body compensates
Normal clinically and hematologically |
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Auto-immune Hemolytic Anemia is what type of anemia?
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Normocytic
Normochromic |
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What are the hereditary hemolytic anemias?
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Hereditary spherocytosis
G-6-PD |
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What type of anemia is sickle cell anemia/trait?
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Normocytic
Normochromic Hemolytic |
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What happens in hemorrhagic anemia?
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Fluid enters vascular system from extravascular space
Decreasing HCT over 2-3 days with no intervention |
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What type of anemia is hemorrhagic anemia?
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Normocytic
Normochromic |
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What will be shown in labs of a hemorrhagic anemia?
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Leukocytosis
Thrombocytosis Increased reticulocytes, peaking at 7-10 days |
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Chemotherapy can cause what type of anemia?
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Macrocytic
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Liver disease can cause what type of anemia?
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Macrocytic
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Preleukemia disorders can cause what type of anemia?
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Macrocytic
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Vitamin B12 and Folate deficiencies are what type of anemias?
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Macrocytic
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What could be the causes of decreased intake of B12?
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Poor diet
Impaired absorption Increased requirements Impaired utilization |
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What could be the causes of impaired absorption of B12?
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Pernicious anemia
Gastrectomy Fish tapeworm Drugs |
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What could be the causes of impaired absorption of folate?
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Sprue
Drugs |
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What could be the causes of increased requirements for B12?
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Pregnancy
Neoplastic disease |
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What could be the causes of increased requirements for folate?
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Pregnancy
Hyperthyroidism |
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What could the be causes of impaired utilization of folate?
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Folic acid antagonists
Trimethoprim |
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What does the Schillings test measure?
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Antibody to intrinsic factor
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How much B12 is stored in your body?
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Enough for 3-4 years
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How long do your folate stores last?
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3-4 months
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What would labs show in a patient with B12 deficiency?
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Oval macrocytes
Decreased serum B12 Hypersegmented neutrophils Increased LDH Low retic count for degree of anemia |
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What would labs show in a patient with folate deficiency?
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Oval macrocytes
Decreased serum and RBC folate levels Low retic count for degree of anemia |
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What test should you perform to rule out malabsorption in folate deficiency?
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Stool fat
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What is the consquence of B12/folate deficiency on DNA?
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Reduced rate of DNA synthesis
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What is the ratio of RNA/DNA in B12/folate deficiency, and what is the consequence?
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RNA/DNA ratio higher than normal
Retards nuclear maturation and mitosis |
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What is the consequence of B12/folate deficiency in RBC formation?
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Nucleus matures more slowly and abnormally
Cells are huge due to poor mitosis Small amounts of cells are produced due to lack of mitotic divisions |
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In hemolytic anemia, symptoms become apparent when the RBC life is reduced to how many days?
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20 days
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What are the intrinsic causes of hemolytic anemia?
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Inherited
Abnormal membrane, enzyme, or hemoglobin |
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What are the extrinsic causes of hemolytic anemia?
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Toxins, microangiopathic, infections, immune
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In hemolytic anemia, an abnormal enzyme produces what specific anemia?
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G6PD
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In hemolytic anemia, an abnormal membrane produces what specific anemia?
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Hereditary spherocytosis
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If a patient presenting with a suspicion of hemolytic anemia has never had a normal Hgb in the past, is it probably congenital or acquired?
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Congenital
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If a patient presenting with a suspicion of hemolytic anemia has had a previous normal Hgb, is it probably congenital or acquired?
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Acquired
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What labs should be ordered in the work-up of hemolytic anemia?
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CBC w/smear
Retic count Coombs test Chemistry profile Haptoglobin |
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What will the Coombs test (DAT) detect?
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Significant amounts of IgG and C3 on red blood cells
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What anemia does the Coombs test typically look for?
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Autoimmune hemolytic anemia
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What are the three possibilities in acquired hemolytic anemia for a Coombs positive?
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Drug induced
Warm antibodies Cold antibodies |
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What are the 5 possibilities in acquired hemolytic anemia for a Coombs negative?
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Hypersplenism
Microangiopathic Chemical Physical Infections |
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What is hypersplenism?
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Increased removal of cellular elements by the spleen
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What are the secondary causes of hypersplenism?
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Acute or chronic infections
Chronic inflammatory disease Congestive splenomegaly Myeloproliferative disorders Leukemia/lymphoma |
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What cells are present in microangiopathic hemolytic anemia?
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Schistocytes
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What is the etiology of microangiopathic hemolytic anemia?
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DIC
TTP HUS Prosthetic heart values |
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What can be seen on the blood smear of a patient with warm-antibody autoimmune hemolytic anemia?
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Macrocytes
Spherocytes Nucleated red blood cells Increased retics |
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What is the mechanism of warm-antibody autoimmune hemolytic anemia?
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Splenic destruction of antibody coated RBCs
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Cold antibody autoimmune hemolytic anemia can occur after what infections?
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Infectious mono
Mycoplasma pneumonia |
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What immunoglobulin is associated with cold-antibody AIHA?
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IgM
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What cancer can cause cold-antibody AIHA?
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Lymphoma
Lymphoproliferative diseases |
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What immunoglobulin is associated with warm-antibody AIHA?
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IgG
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What will be decreased in warm-antibody AIHA?
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Haptoglobin
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What are the causes of warm-antibody AIHA?
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Lymphoma
Autoimmune diseases (SLE, RA) Drugs |
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What are the congenital hemolytic anemias with membrane abnormalities?
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Hereditary spherocytosis
Hereditary elliptocytosis |
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What are the congenital hemolytic anemias with enzyme deficiencies?
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G6PD deficiency
Pyruvate kinase deficiency |
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What are the congenital hemolytic anemias with hemoglobinopathies?
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Sickle cell anemia
Hemoglobin C and SC disease |
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Hereditary spherocytosis is what kind of trait?
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Autosomal dominant
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Hereditary spherocytosis is most common in people of what ancestry?
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Northern European
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What is hereditary spherocytosis a defect of?
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Abnormality of the membrane protein ankyrin
Spectrin deficiency |
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What is spectrin?
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Major internal portion of RBC membrane
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What is the mechanism of hereditary spherocytosis?
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Defects in vertical stabilization of phospholipid bilayer of RBC membrane cause separation of spectrin-phospholipid bilayer
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What test should be run in suspicion of hereditary spherocytosis?
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Osmotic fragility test
Normal on top HS on bottom |
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What is the frequency of sickle cell anemia?
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1 in 400-500 African Americans
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What is the amino acid substitution responsible for sickle cell anemia?
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Valine for glutamate at position 6 on beta chain
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What Hgb is present in sickle cell anemia?
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Hgb S
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How is Hgb S formed?
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Abnormal beta chains in sickle cell anemia combine with alpha chains to form Hgb S
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How are the cells distorted in sickle cell anemia?
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at low oxygen tensions, the Hgb S is poorly soluble and distorts cell
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What tests should be run for sickle cell anemia?
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CBC w/diff
Sickledex Hgb Electrophoresis |
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What type of anemia is sickle cell anemia?
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Normocytic
Normochromic |
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What will be seen on the blood smear of a patient with sickle cell disease?
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Sickle cells
Target cells NRBCs Howell-Jolly bodies |
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What will the labs show in a patient with sickle cell disease?
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Increased WBCs and platelets
Retic count 10-20% Positive solubility Hgb S |
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What is the advantage of sickle cell disease?
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Not susceptible to malaria
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What does the presence of Howell-Jolly bodies indicate?
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Accelerated erythropoiesis
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When is sickle cell disease usually first detected?
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6 months of age
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What will the labs in a patient with sickle cell trait show?
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Normal blood smear
Positive solubility 55-60% Hgb A 35-45% Hgb S |
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How long do sickle cells live?
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12-20 days
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What conditions contribute to increased sickling of cells?
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Decreased O2
Decreased pH Increased body temp |
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What are the complications of sickle cell trait?
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Patient usually asymptomatic
Hematuria Splenic infarct Normal lifespan |
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Hemoglobin C disease causes what severity of anemia?
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Mild to moderate
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What finding is common upon physical exam of a patient with hemoglobin C disease?
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Splenomegaly
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What is seen on the blood smear of a patient with hemoglobin C disease?
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Target cells
Hemoglobin crystals |
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How is hemoglobin C diagnosed?
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Electrophoresis
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What are the stressors of G6PD?
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Antimalarials
Sulfonamides Nitrofurans Fava beans Infection DKA |
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What leads to hemolysis in G6PD deficiency?
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Oxidant compounds (stress)
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What shunt is the sole source of NADPH in RBCs?
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hexose-monophosphate shunt
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What is seen on the smear of a patient with G6PD deficiency?
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Spherocytes
Blister cells Burr cells |
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What is the usual condition of a person with G6PD deficiency?
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Usually asymptomatic until times of stress
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Pyruvate kinase deficiency is what kind of genetic disorder?
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Autosomal recessive
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What happens in pyruvate kinase deficiency?
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Reduced ATP formation causes RBC rigidity, resulting in hemolysis
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In what patient population is pyruvate kinase deficiency usually seen?
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Children
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What do patients with pyruvate kinase deficiency present with?
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Splenomegaly
Cholelithiasis Jaundice |
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What is primary erythrocytosis called?
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Polycythemia vera
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What is anisocytosis?
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Variation in size of RBCs
Correlates to RDW |
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Poikilocytosis is what?
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Variation in shape
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What will spherocytes do to the MCHC?
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Increase it
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What RBC abnormality causes target cells?
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Too much membrane for the amount of hemoglobin
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What diseases cause target cells?
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Liver disease
Thalassemias Hemoglobinopathies (S,C) |
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What RBC abnormality causes burr cells?
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Change in osmotic pressure
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What condition causes burr cells?
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Uremia
Dehydration |
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What will hypochromia do to the MCH and MCHC?
|
Decrease them
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What cells display polychromia, and what color is it?
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Retics
Slight blue or gray tinge |
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What is the defect that causes basophilic stippling?
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Young red cell or heme synthesis defect
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What diseases cause basophilic stippling?
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Thalassemia
Lead poisoning |
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What are Howell-Jolly bodies?
|
Dark purple, round inclusions of DNA
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In what patients are Howell-Jolly bodies usually seen?
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Post-splenectomy patients
Sickle cell anemia |
