Blood Diseases Part 2

  1. Vitamin B12 deficiency or pernicious anemia
    • Pernicious anemia is a type of megaloblastic anemia
    • Due to poor vitamin  B12 absorption from the GI tract
  2. Vitamin B12 deficiency Caused by intrinsic factor deficiency, a protein produced by the stomach that binds to vitamin B12
    • 1} When the stomach does not make enough intrinsic factor, the small intestine cannot properly absorb vitamin B12 and the intrinsic factor
    • {2} Without vitamin B12 and intrinsic factor, immature rbcs membranes rupture easily, thus fewer rbcs and reduced O2-carrying capacity
  3. Causes of pernicious anemia
    • Weakened stomach lining (atrophic gastric mucosa)
    • {2} Autoimmunity against gastric parietal cells that make intrinsic factor
    • {3} Autoimmunity against intrinsic factor itself
    • {4} Bacterial infection causing pathological conditions that either
    •      {a} Impair vitamin B12 absorption
    •    {b} Enhance vitamin B12 elimination
  4.  Sources of vitamin B12
    {1} Animal products{2} Vitamin B12 supplements
  5. Symptoms of pernicious anemia
    • {1} Abdominal distress
    • {2} Burning of the tongue
    • {3} Central nervous system effects
  6. Folic acid deficiency anemia
    Due to insufficient folic acid (folate, vitamin B9) levels essential for body growth and to synthesize DNA

    Low serum folic acid levels conclusive for this disease
  7. Folic acid deficiency anemia - Absorbed in small intestines and absorption is affected by (5)
    • {1} Chronic alcoholism
    • {2} Poor nutrition
    • {3} Pregnant and lactating females
    • {4} Kidney disease
    • {5} Inflammatory bowel disease
  8. Hemolytic anemia
    Insufficient rbcs in blood due to premature destruction
  9. Hemolytic anemia Causes include
    • {1} Inherited abnormalities
    •      {a} Hemoglobin defects
    •      {b} Enzyme defects
    •      {c} rbc membrane defects
    • {2} Infections microorganisms
    • {3} Medications
    • {4} Immune disorders
  10. Hemolytic anemia - Significant rbc destruction leads to
    • {1} Caused by excess yellow-orange bile pigments or bilirubin, a chemical produced when the liver breaks down rbcs
  11. Yellow-orange color is evident in 
     { a} Sclera   {b} Skin   {c} Urine   {d} Feces
  12. Hemolytic anemia - Treatments
    • {1} Splenectomy
    • {2} Blood transfusions
    • {3} Antibiotics for infections causing hemolytic anemia
    • {4} Immunosuppressive therapy for immune disorders causing hemolytic anemia
    • {5} Discontinue medications causing hemolytic anemia
  13. Hemoglobinopathies
    Diseases where genetic defects produce abnormal hemoglobins and/or anemia
  14. Types of Hemoglobinopathies
    • Sickle cell anemia
    • Thalassemia
    • Polycythemia vera
  15. Sickle cell anemia
    • {1}Autosomal recessive inherited disease
    •      {a} Homozygous- full blown disease
    •      {b} Heterozygous- Sickle cell trait
    • {2} Found in ~10% of African-Americans
  16. Sickle cell anemia is cause by
    • {3} Caused by an abnormal type of hemoglobin called hemoglobin     S that distorts the shape of rbcs under low O2 conditions
    • {a} Hemoglobin S molecules form long crystals by cross-linking with each other
    • {b} As O2 is released from rbcs, the rbcs become sickle-shaped
    • {c} Sickle-shaped rbcs are inflexible and rigid causing mechanical obstruction of small arterioles and capillaries
    • {d} Pain and ischemia occurs ultimatelyn leading to organ failure
    • {e} Sickle-shaped rbcs more fragile than normal rbcs leading to rbc hemolysis (hemolytic anemia)
  17. Sickle cell anemia Treatments
    • {a} Narcotic analgesics to manage pain from sickle cell crisis
    • {b} Blood transfusions and fluid replacement to expand blood volume
    • {c} O2 for reperfusion or occluded arteries
Card Set
Blood Diseases Part 2
Blood Diseases Part 2