Card Set Information

2012-08-27 20:23:59
Lab Tech ll

Lab Tech ll
Show Answers:

  1. What is anemia?
    decrease in the oxygen carrying capacity of the blood, decrease in RBC count
  2. What test can we do in the clinic to test for anemia?
    PCV - a decrease in PCV indicates anemia
  3. Is anemia a disease?
    no, its a clinical sign
  4. What are the clinical signs of anemia?
    • pale mucous membranes
    • weakness, tire easily
    • syncope
    • tachycardia
    • tachypnea
    • cool extremities
    • heart murmur
  5. What is syncope?
  6. Is a heart murmur caused by anemia reversable?  And if so, how is reversed?
    • yes
    • as soon as anemia is corrected, heart murmur is corrected
  7. Can clinical signs of anemia vary?
    yes, the more anemic the more severe the clinical signs.
  8. Where are red blood cells mainly made?  Where are other places red blood cells are made?
    • bone marrow
    • can also be made in the spleen, nodes, and liver
  9. How long is the life span of red blood cells in dogs and cats?
    • dogs:  110 days
    • cats:  70 days
  10. What are red blood cells and what do they do?
    • contain hemoglobin
    • carries oxygen
  11. If loss of red blood cells is greater than the production of red blood cells, then what occurs?
  12. Can anemia be life threatening?
  13. Where are red blood cells broken down?
    in the reticuloenothelial system
  14. What does hemoglobin break down to?
    • globin
    • iron
    • unconjugated bilirubin
  15. What parts of hemoglobin are reused and which are not?
    • globin and iron are reused
    • unconjugated bilirubin is taken to the liver and changed to conjugated bilirubin which is then passed in urine and feces
  16. What is erythropoietin?
    hormone that is released to stimulate the production of RBC
  17. Where does erythropoietin come from?
    the juxtaglomerular apparatus of the kidney
  18. How is erythropoietin stimulated?
    when oxygen levels drop below a certain level erythropoietin is released from the kidney.  this stimulates the bone marrow to release RBCs and in crease RBC production
  19. If erythropoietin is present in anemia then is it regenerative or nonregenerative?
    regenerative anemia
  20. How do we evaluate RBCs?
    • PCV
    • RBC count and hemoglobin
    • erythrocyte morphology
    • reticulocyte count
    • bone marrow aspiration
  21. When is a reticulocyte count useful?
    only when we know the patient is anemic and when we want to determine if the anemia is responsive or non-responsive
  22. What is a normal PCV for dogs, cats, horses, cows?
    • dogs:  45%
    • cats:  37%
    • horses:  42%
    • cows:  34%
  23. Which test is the most accurate to test for anemia?
  24. With what kind of stain do we see reticulocytes?
  25. Can we stain RBCs with NMB and then with Diff Quik?
  26. How many reticulocytes are considered normal in dogs?
  27. Reticulocytes increase with which type of anemia?
  28. When we look at for reticulocytes in cats which ones do we count?  Which ones do we not count?
    cont the aggregate ones and don't count the punctate ones
  29. Do normal large animals have reticulocytes in the peripheral blood?
  30. When do we see reticulocytes in ruminants?
    • in responsive anemia
    • no need to count them because if any exist then they have responsive anemia
  31. Where do we find reticulocytes in horses?  Do they ever have any in the peripheral blood?
    • bone marrow
    • no
  32. If a dog is anemic how many reticulocytes can we see?
    up to 50%
  33. How do we do a manual reticulocyte count?
    • mix blood with NMB (1:1)
    • let it sit in the NMB for 10 minutes
    • make a blood smear
    • count reticulocytes per 1, 000 RBCs
    • divide by 10 to get %
  34. Why do we need to do a corrected reticulocyte count?
    must correct for the fewer mature RBCs in an anemic animal
  35. How do we do a corrected reticulocyte count?
    multiply observed retic count times observed PCV/normal range (45% for dogs, 35% for cats)

    retic count (%) x actual PCV/normal PCV
  36. Will the corrected reticulocyte count always be lower than the observed count?
  37. How do we get an absolute retic count?
    multiply corrected retic %'s by RBC count
  38. What are the two causes of regenerative anemia?
    • blood loss
    • hemolytic
  39. What causes blood loss anemia?
    • bleeding
    • GI parasites
  40. What causes hemolytic anemia?
    IMHA, HBHA, blood parasites
  41. What is IMHA?
    immune mediated hemolytic anemia
  42. What is HBHA?
    heinz body hemolytic anemia
  43. What does hemolytic anemia mean?
    more RBCs are being destroyed than replaced
  44. How long can it take for us to see a reticulocyte response?
    may take up to 7 days
  45. What is anisocytosis?
    variation in size of RBC
  46. Which animal is anisocytosis normal?
  47. What type of anemia do we see anisocytosis?
    responsive anemias
  48. What is polychromasia?
    variation in RBC color from blue to red
  49. What causes polychromasia?
    increased reticulocytes
  50. What are Howell Jolly Bodies?
    • nuclear reminant
    • one per cell
    • blue dot anywhere in the cell
  51. What can we confuse Howell Jolly Bodies with?
  52. What kind of anemia do we usually see Howell Jolly Bodies in?
    responsive anemia
  53. What is another name for a nucleated RBC?
  54. When will we see metarubricytes?
    in responsive anemias
  55. What can machines confuses metarubricytes with?
  56. Is it possible to see some metarubricytes in normal animals?
  57. If we have an animal with nonspecific GI symptoms and metarubricytes what is the most likely cause?
    lead poisoning
  58. How do we do a corrected WBC count?
    • count nucleated RBCs as part of differential (100 cells)
    • calculate absolute number by multiplying % x leukocyte count
    • subtract from total leukocyte count
  59. What is autoagglutination?
    clumpingof RBCs
  60. What can agglutination be easily confused with?
  61. Which type of anemia is agglutination usually seen in?
  62. What are spherocytes?
    • round RBC with no central pallor and usually smaller than a normal RBC
    • stain denser than a normal RBC
  63. Which type of anemia are spherocytes usually seen in?
  64. What are spherocytes often associated with?
  65. What are heinz bodies?
    denatured hemoglobin
  66. Where are heinz bodies usually located?
    on edge of RBC
  67. What do heinz bodies look like when stained with DQ?  NMB?
    • DQ:  refractile
    • NMB:  blue
  68. What can heinz bodies be confused with in cats?
    erythrocyte refractile bodies
  69. What usually causes heinz bodies?
  70. What types of toxicities cause heinz bodies?
    • acetominophen
    • methylene blue (found in cleaners)
    • onions
  71. What is basophilic stipling?
    blue dots in RBCs stained with DQ
  72. What usually causes basophilic stipling?
    lead poisoning
  73. Lead toxicity may cause what?
  74. What is mycoplasma haemofelis?
    small blue dot on edge of RBC in cats
  75. What is the first thing we look for when we have an anemic cat?
    mycoplasma haemofelis
  76. What can mycoplasma haemofelis cause?
    feline infectious anemia
  77. What other parasites can cause anemia?
    • ehrlichia
    • anaplasma
    • babesia
  78. What tests can determine blood parasites?
    • snap
    • PCR
    • serological tests
    • blood smear
  79. What is affected by non-regenerative anemia?
    bone marrow
  80. What are the 4 mechanisms of non-regenerative anemia?
    • destruction
    • depression
    • depletion
    • degeneration
  81. What causes non-regenerative anemia?
    • renal disease
    • infections
    • drugs
    • neoplasia
  82. What is MCV stand for?  What is it?
    • mean corpuscular volume
    • average size of RBC
  83. How do we determine the MCV?
    PCV divided by RBC count (in scientific notation) x 10
  84. What is it called if MCV is normal?  Above normal? Below normal?
    • normal:  normocytosis
    • above normal:  macrocytosis
    • below normal:  microcytosis
  85. What are most macrocytic anemias?
  86. What is microcytic anemia usually due to?
    Fe deficiency
  87. What does MCHC stand for?  What is it?
    • mean corpuscular hemoglobin concentration
    • average hemoglobin in RBC
  88. How do we determine the MCHC?
    HbG/PCV x 100
  89. What is the normal range for MCHC?
    normochromia:  between 31 and 36
  90. Does hyperchomia exist?
  91. If a MCHC is smaller than 31 what does it mean?
  92. What is hypochromia?
    large pale area in center of RBC
  93. What causes hypochromia?
    decrease in HbG due to blood loss or decrease in iron
  94. Why would we do a bone marrow biopsy?
    • to find a cause for unexplained increase or decrease in blood cells
    • can tell if anemia is regenerative
    • evaluate normal WBCs and RBCs
    • can determine if cells are abnormal

  95. What is wrong with these RBCs?

  96. What is on this WBC?
    Ehrlichia or Anaplasma

  97. What is wrong with these RBCs?

  98. What parasite is on these RBCs?

  99. Which ones are aggregates and which ones aare punctate?
    • aggregates:  the RBCs with more blue dots
    • punctate:  the RBCs with only a couple blue dots

  100. What is on these RBCs?
    heinz bodies

  101. What is on these RBCs?
    heinz bodies

  102. What is on this RBC?
    howell jolly body

  103. What is wrong with these RBCs?

  104. What does this indicate?

  105. What is this?
    mast cell

  106. What is this?

  107. What are on the edges of this cat's RBCs?
    mycoplasma haemofelis

  108. What is wrong with these RBCs?

  109. What are the smaller RBC's called?
  110. List 3 general physiologic mechanisms by which anemias are produced.
    • blood loss
    • hemolysis
    • bone marrow destruction
  111. List 5 different specific causes of anemia.
    • bleeding
    • parasites (internal and external)
    • renal disease
    • infections
    • drugs
    • neoplasia
  112. List 2 ways the lab findings in autoimmune hemolytic anemias differ from those in other types of anemias.
  113. What is the significance of a Heinz body hemolytic anemia?  List three causes of a HBHA.
    • denatured hemoglobin
    • acetominophen, methylene blue (in cleaners), onions
  114. List 4 findings you may see in a Diff Quik stained blood smear from an animal with a responsive anemia.
    • autoagglutination
    • spherocytes
    • heinz bodies
    • basophilic stipling
    • mycoplasma haemofelis
  115. A dog has a PCV of 18%.  You count 36 reticulocytes/1000 rbcs on the blood smear.

    What is the observed reticulocyte count?
    What is the corrected reticulocyte count?
    Is this a responsive anemia?
    In the absence of a reticulocyte count, how else could you determine if the anemia is responsive?
    • 3.6%
    • observed retics x (observed PCV/normal PCV)...3.6% x (18%/45%) = 1.4%
    • yes, slight
    • check a blood smear for erythrocyte morphology
  116. A dog has a PCV of 21%, an erythrocyte count of 3,000,000/dl and a hemoglobin of 2 gm/dl.

    What is the MCV?
    What is the MCHC?
    Based on the above how would you classify the anemia?
    • (PCV/RBC)x10...(21/3)x10=70
    • (HbG/PCV)x100...(2/21)x100=9.5
    • normocytic, hypochromic anemia