Hematology Case Histories - Case 11 Polycythemia

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Hematology Case Histories - Case 11 Polycythemia
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Basics

• A 62-year-old male complained of weakness,
  headache, light-headedness, and fatigue. Upon
  physical examination, the following information
  was available
• Erythrocytes 8.5 million/cu mm
• Leukocytes 12,500/cu mm
• Thrombocytes 400,000/cu mm
• Hct 58
• O2 saturation (arterial) 94
• Serum erythropoietin Undetectable
• Erythrocytes and leukocytes were immature in the
  peripheral blood smear.
• Spleen was enlarged. determined therapy of choice
  was phlebotomy,
• 300-500 mL every other day, until the hematocrit
  was lt45 with the
• possibility of myelosuppressive therapy, if
  needed.

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• What are Erythrocytes?
• Red blood cells

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• 2. What is the normal range for red blood cell
  count?
• RBC (varies with altitude) Note cells/mcl
  cells per microliter
• male 4.7 to 6.1 million cells/mcl
• female 4.2 to 5.4 million cells/mcl

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• 3. What are leukocytes?
• White blood cells
• 4. What is the normal white blood cell count for
  leukocytes?
• 4,500-10,000 white blood cells/mcl (cells per
  microliter)

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• What are thrombocytes?
• Platlets
• 6. What is a normal thrombocyte count?
• 150,000 to 400,000/mm3

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• What is a hematocrit?
• The percentage of whole blood that is composed
  of RBC
• 8. What is a normal hematocrit?
• Males 42-50
• Females 36-44

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• 9. what is erythropoietin?
• A growth factor hormone that tells stem cells in
  bone marrow to grow into RBCs. It increases the
  amount of RBCs in the blood.
• What is a normal value for arterial oxygen
  saturation?
• 94-100

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• 11. How do the patients test results compare
  with normal blood test results?
• The patient has more of everything
• 12. What are possible causes for an increased
  hematocrit?
• dehydration, diarrhea, burns, erythrocytosis
  (excessive rbc production), or polycythemia

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• 13. What is hypoxemia, and why can it be
  eliminated as a cause?
• Hypoxemia is a low oxygen content, and this
  person has normal oxygen levels.
• 14. What are Pluripotential hemopoietic stem
  cells?
• Precursors to blood cells
• 15. What does pluripotent mean?
• A type of cell that can differentiate into many
  different types

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• 16. What is the disorder of this individual?
• The disorder of this individual is polycythemia.
  Polycythemia vera is an
• Abnormal increase in blood cells (primarilyred
  blood cells) resulting from excess production by
  the bone marrow.

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• 17. Why are the arterial O2 saturation and
  erythropoietin levels important in making this
  decision?
• The arterial O2 saturation and erythropoietin
  levels are important in confirming that the
  increased hematocrit is not due to hypoxemia or
  an abnormally elevated
• erythropoietin level. The O2 saturation level
  would indicate if there is a physiologic
• stimulus for the increased erythrocyte
  production.

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• 18. Define phlebotomy
• Phlebotomy is the letting of blood for
  transfusion pheresis, diagnostic testing, or
  experimental procedures.
• 19. How does phlebotomy help correct this
  problem?
• Phlebotomy (removal of the whole blood) removes
  both blood cells and plasma. The plasma volume is
  replaced within days, whereas the erythrocytes
  take several weeks to be replaced.

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• 20. Define myelosuppressive therapy.
• Myelosuppressive therapy is therapy for the
  suppression of the bone marrow's production of
  blood cells and platelets.
• 21. Why may myelosuppressive therapy be needed?
• Myelosuppressive therapy may be needed to
  suppress the erythrocyte production in the
  myeloid tissue if the hematocrit continues to
  rise after the phlebotomies.