Transcript Anemia

Anemia
Clinical Pathology
Kristin Canga, RVT
Reading Assignment
• Page 68 – Lab Pro book
• ‘Clinical Application’ box (Iron
Deficiency Anemia) on pg. 12 of A&P
book
• Pages 55 – 57 Lab Pro book (about
counting reticulocytes)
Anemia
• Literally means “no blood” but clinically means an
______________ ____________________below
normal in any of the following values:
– ________________________________________
– ________________________________________
– ________________________________________
• In other words, anemia is a condition of reduced
oxygen carrying capacity of RBCs
– Rate of RBC ______________________ = decreased
– Rate of RBC ______________________ = increased
Aiding in Classification and Diagnosis
of Anemia
• A thorough ___________ must be obtained.
– This helps the doctor know: what the patient has been
____________ /____________, where they have been,
how long they have been suffering, and possibly
_________ the anemia has occurred.
• A physical exam should be completed.
– Put your ____________ on the animal!
– Look for _____________, _____________,
_____________, active bleeding, elevated
heart/respiratory rates, etc…
• A complete _____________evaluation is a MUST.
Petechia
Ecchymosis
PATIENT HISTORY
1. __________________________of clinical signs
– ______________ onset suggests acute
_________________ or ______________
– ______________ onset suggests chronic
______________ or bone marrow depression
2. Evidence of blood loss
– ______________
– ______________
– ______________
– Blood in ______________
PATIENT HISTORY
3. ____________________________
4. Existence of an underlying condition or prior illness
– ____________________________
– ____________________________
– ____________________________
5. Exposure to drugs
- human ______________ , ______________
6. Exposure to toxic ______________ in the
______________
- ______________ , poisonous _________,
______________
PHYSICAL EXAMINTION
1. ______________
– Suspect: infection, leukemia, hemorrhage, or
hemolysis
2. Character of ___________________:
–
–
–
–
–
______________
______________ – liver disease or hemolysis
______________ + ______________ = hemolysis
______________ - hypoxia
______________ or ______________ = platelet or
vascular defect
PHYSICAL EXAMINATION
3. Palpation
– ______________
– ______________
– ______________
– ______________
4. ______________ signs of underlying disease
5. External wounds
– ______________
– ______________
– ______________
Classification and Dx of Anemia
• Classification is to aid in discovering the _______________
and to help guide __________________.
• Remember: Anemia is not a __________________, but a
sign of an underlying health concern.
• Anemia may be considered ___________________ or
________________________ and is generally
classified/diagnosed in one of two different ways:
1. By RBC ________ and ____ concentration
a. RBC ____________________ (MCV, MCHC)
2. By bone marrow response
a. ________________________________
b. ________________________________
LABORATORY EVALUATION
Initial laboratory tests to evaluate the anemic patient
include (but not limited to):
1. ______________ (and color of supernatent plasma)
2. Total ______________ protein
3. Examination of ______________ and
____________________________
4. Total ______________ count
5. ______________ estimation
6. ______________ concentration
7. Total ______________ count
8. ______________ **
9. ______________ evaluation **
PCV: Test yourself 
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What is it measuring?
Normal ranges for dogs?
Normal ranges for cats
Plasma (supernatent) colors?
Plasma Protein
• What is it measuring?
• How is it measured?
• What is normal range for dogs and cats?
How Many Cells should you have?
• As a rule, the following values should be considered:
– RBC total numbers should be in the ______________ .
(106/μL)
– Plt total numbers should be in the ______________ of
______________ . (200,000 – 500,000/μL)
– WBC total numbers should be in the ______________ to
____________________________ . (6,000 – 17,000/μL)
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•
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•
•
Neutrophils: 60 – 77%
Lymphocytes: 12 – 30%
Monocytes: 3 – 10%
Eosinophils: 2 – 10%
Basophils: rare (<2%)
In dogs and cats
Blood Film Evaluation and WBC
Differential
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•
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•
•
What area are you evaluating?
How are cells arranged?
Are RBCs normal?
How many WBCs are counted?
How many fields are counted for plt.
estimation?
• What is calculation for plt. estimation?
Total WBC Count
• Overall count should be in ______________ to
____________________________ . (6,00017,000)
• Total count calculated by machine

Manual hemacytometer is rare in clinic and diluent is no
longer available.
• Increased WBCs = ______________
• Decreased WBCs = ______________
Hemoglobin Calculation
• Done by machine.
• Aids us in calculating average
______________ of RBCs (_______)
• Aids us in calculating average ______
concentration within RBCs (_______)
• Can aid in calculating average
______________ of Hb within average RBC.
(_______)
*** MCH is LEAST accurate***
Classifying Anemia by RBC indices
• MCV: ____________________________
• MCHC: ____________________________
• MCH: ____________________________
Rules of Thumb (ROTs):
• Hb concentration is ~_______ of PCV (in g/dL)
• Total RBCs are ~_______ of PCV (in millions)
Classification by RBC Indicies
• Recall that MCV (mean corpuscular volume)
describes the average volume of the individual RBC
– Normal MCV = _____________________
– Increased MCV = _____________________
– Decreased MCV = _____________________
FORMULA: (PCV / Total RBC) X 10 = MCV (femtoliters)
Normal MCV = canine: 60 – 77 fl.
feline: 40 – 55 fl.
Let’s do the math:
• The MCV of a patient with a PCV of 12% is:
– Step 1: Recall the formula:
• (_______/ ______________) X 10 = MCV (femtoliters)
– Step 2: Remember the ROT
• total RBC ≅ _______ PCV so:
• ______________ = ______________
– Step 3: plug in the numbers
• ___________________________________
• Is this normal for k9/fel?
• How would you classify this RBC?
Possible Causes of Abnormal MCV
• Possible causes of Increased MCV:
– Increased _____________________activity = #1
• Reticulocytosis
– Congenital (___________&_________________)
– Cats with _______ (+/- anemia)
• Possible causes of Decreased MCV:
– ______________ deficiency = #1
– Congenital disorder (_______and ______________)
Classification by RBC Indicies
• MCHC (mean corpuscular hemoglobin
concentration):
– Describes the ratio of the _______of hemoglobin to
the ______________in which it is contained
(concentration of hemoglobin in the avg. RBC)
– Normal MCHC = ______________
– Decreased MCHC = ______________
– High MCHCs = artifact WHY???
Formula
(______ / ______) X ______= MCHC (g/dL)
Normal MCHC = canine: ______________g/dL
feline: ______________g/dL
• Remember the ROTs?
• If you calculate MCHC by estimating Hb, the
values will always come out the same.
• Lets do the math!
Using the ROT
• The MCHC of a patient with a PCV of 33% is:
– Step 1: Recall the formula
• (_______ / _______) X _______= MCHC (g/dL)
– Step 2: Remember the ROT
•
•
•
•
Hb ≅ _______ of PCV so:
_______= _______
Step 3: Plug in the numbers
__________________________________________
Using actual numbers
• The patient’s Hb is 9g/dL, and their PCV is 30%
• Formula: (_______/_______) x _______
• SO: _______________________=_____g/dL
• Is this normal for k9? Fel?
• How would it classify the RBC?
Low MCHC usually results from:
• Severe _______deficiency
• Marked, regenerative anemia
– ____________________________RBCs that do not
yet have their full complement of Hb.
MCHC increase:
• Presence of ______________, ______________,
and ___________ can interfere with tests and
______________increase MCHC
• True _____________________anemia cannot
exist; the erythrocyte cannot be oversaturated
with ______.
Morphologic Classification of Anemia
by RBC Indicies
MCHC normal
MCHC decreased
MCV normal
Normocytic
Normochromic
Normocytic
Hypochromic
MCV increased
Macrocytic
Normochromic
Macrocytic
Hypochromic
MCV decreased
Microcytic
Normochromic
Microcytic
Hyprochromic
Normocytic ; Normochromic
Macrocytic
Microcytic
Hyperchromic Hypochromic
Calculating MCH
• You will need to know HOW to do this for VTNE,
even though it is the _______accurate of the
indices.
• Calculates the average _______of Hb contained
in average RBC.
• (_______/_______) x _______= MCH in
picograms (pg)
– Normal ranges:
• K9: _______pg
• Fel: _______pg
Let’s do the Math
• The MCH of a patient with a PCV of 54% is:
• Step 1: Remember the formula
– (_______/_______) x _______= MCH
• Step 2: Remember the ROT
– Hb ≅ _______ PCV and RBCs ≅_______ PCV
• _______ = _______ and _______ = _______
• Step 3
– Plug in the numbers:
• _____________________pg
Diagnosis of Anemia According to
Bone Marrow Response
• Most applicable way to differentiate between:
– ________________________ and
________________________ anemia
Bone Marrow Response
Regenerative anemia
– Characterized by evidence of increased ______________
and delivery of new erythrocytes into ______________
(usually within 2-4 days).
– Usually suggests bone marrow is responding appropriately
to either:
• _____________________ (acute or chronic; internal or external)
or
• _____________________ (intravascular or extravascular)
– Involves determining whether absolute
_____________________ numbers are increased in the
blood.
Bone Marrow Response
Non-regenerative anemia
– Lack of circulating ______________ RBCs in the face
of _______ indicates a nonregenerative anemia and
likely results from bone marrow ______________.
• Either reduced erythropoiesis or defective erythropoiesis
– No response evident in ______________blood.
(usually ______________; ______________)
– _____________________examination may be helpful
with the diagnosis.
Regenerative Anemia
1. Blood Loss Anemia
Acute _____________________– relatively large amount of
blood lost in a brief period. (______________;
______________)
– PCV initially = ______________
– Reticulocytes should appear ~_______ hrs (peak within ~ 1
week)
– Causes:
a. ______________
– Internal or external
– Accidental or surgical
b. ______________disorders
c. Bleeding ______________ or large ______________
Regenerative Anemia
Chronic blood loss (_______Deficiency Anemia) – lost
______________and ______________for a period of
time.
a. Parasites
– ______________, _______, blood-sucking _______,
coccidia spp.
b. GI ulcers and neoplasms
c. Inflammatory bowel disease
d. Overuse of ______________donors
• Note: neonates can become iron deficient due to
lack of adequate dietary _______ intake.
Iron Deficiency Anemia
• Body compensates for anemia by lowering ______________ affinity, preferential shunting of blood to vital
_______, increased ______________output (tachycardia),
and increased levels of _____________________.
• With decreasing _______ stores, erythropoiesis is limited
and RBC’s become ______________and deficient in
_______ (______________and _____________________).
– Hallmark of iron deficiency anemia is decreased _______.
• Keratocytes & schistocytes
• Clinical signs include: lethargy, weakness, decrease exercise
tolerance, anorexia, lack of grooming, mild systolic
murmur.
Regenerative Anemia
• 2. _____________________: increased rate of
erythrocyte _______________________ within
the body.
a. Immune-mediated
-_____________________
-_____________________
- Incompatible _____________________
a. Blood Parasites
-Hemotrophic Mycoplasmas
- ______________________spp.
- ________________________
Cytauxzoon felis inclusions
Regenerative Anemia
c. Heinz body anemia
– Plants
• Onions*, garlic
– ______________________
– Drugs or Chemicals
• (______________________, Propylene glycol, Zinc,
Copper, Methylene blue, Naphthalene,
______________________, phenothiazine, benzocaine
– Diseases (in cats)
• Diabetes mellitus
• Hyperthyroidism
• Lymphoma
Regenerative Anemia
d. ______________________ induced
hemolysis
RBC glycolysis is inhibited by hypophosphatemia;
no glycolysis = no ATP (energy) for RBC = cell
lysis
• Diabetic cats
• Enteral alimentation
Regenerative Anemia
e. Other Microorganisms
– ______________________
• Clostridium spp. and Leptospirosis (cattle)
– ______________________
• ______________________
f. ______________________intoxication (usually
calves)
– can also occur as a result of inappropriate administration of
______________________ therapy.
g. ______________________ RBC defects
– ______________________ (shortened RBC lifespan)
– RBC membrane transport defects
– Chronic intermittent hemolytic anemia (Abyssinian and
Somali cats)
Regenerative Anemia
h. Miscellaneous
– Metabolic disorders (anything that interferes with
synthesis of ______________________, RBC,
etc. or anything that interferes with
______________________processes of RBC)
Non-regenerative Anemia
• Most non-regenerative anemias are
______________________
• Further sub-classified based on whether
______________________ (neutrophil
production) and ______________________
(platelet production) are also affected.
• Animals with non-regenerative anemia in
conjunction with ______________________
(neutropenia and thrombocytopenia) usually have
____________ cell injury.
– Possible causes: drugs, toxins, viruses (FeLV), radiation,
and immune-mediated stem cell injury.
Non-regenerative Anemia
1. Reduced ______________________
a.
b.
c.
d.
Chronic ______________________ disease
Endocrine deficiencies
Inflammation and neoplasia
Cytotoxic damage to the
______________________
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Estrogen toxicity
Cytotoxic cancer drug therapy
Chlormphenicol (cats)
Radiation
Other drugs
Non-regenerative Anemia
e. Infectious agents
– FeLV
– ______________________ spp.
– ______________________
f. Immune-mediated
– Continued treatment with recombinant erythropoietin
– ______________________ aplastic anemia
g. Congenital/inherited
h. ______________________ and other
______________________ disorders
Non-regenerative Anemia
2. Defective ______________________
a. Disorders of ___________ synthesis
–
Iron, copper, and pyridoxine deficiencies; lead toxicity; drugs
b. Folate and ____________ deficiencies
c. Abnormal ______________________
•
can be inherited, drug-induced or idiopathic
Reticulocyte Count
• Probably the most important diagnostic tool used
in the evaluation of anemia.
• Fewer _____________ erythrocytes are present
in anemic animal; more
______________________are present.
• Expressed as a _____ of the RBCs present.
• The lifespan of a normal RBC is about 110 days
(dogs) and 68 days (cats).
– Bone marrow should replace ___ % of the RBCs daily
so the reticulocyte count should be _____-______%.
Reticulocyte Count
1. Gently mix 4 drops of blood with 4 drops of new
methylene blue in a test tube.
2. Let mixture stand for 15 minutes
3. Use 1 drop of mixture to prepare a diagnostic
blood film and observe under high-power, oilimmersion field.
4. Count 1,000 RBCs while separately keeping track
of the number of reticulocytes (only aggregate
form)
5. Divide the reticulocyte number by 1,000 and
convert to a percentage. (Multiply by 100)
Example Reticulocyte count
• If you see 10 retics on slide 1 and 15 on slide
2, your total is 25 reticulocytes.
• 25/1000 = 0.025 x 100 = 2.5%
Corrected Reticulocyte Count
• Performed to take in account the reduced number of circulating
RBC’s in the anemic animal.
– Called CRC or Corrected Reticulocyte Count
– FORMULA:
• Observed retics % x PCV / normal PCV
• (Normal PCV: use 45% for dogs and 35% for cats)
Ex: 2.5% X 30% / 45% = 1.67%
Note: This calculation is necessary because the reticulocyte count is
misleading in anemic patients. The problem occurs because the
reticulocyte count is not really a count but rather a percentage: it reports
the number of reticulocytes as a percentage of the number of red blood
cells. In anemia, the patient's red blood cells are reduced, creating an
elevated reticulocyte count.