ClinPath1

Question 1

CBC Review

Answer 1

• PVC
• TP
• RBC
• WBC
• Hgb
• Indices
• Differential
• Platelet estimate

Question 2

Reticulocyte Count

Answer 2

– immature RBC- still in the bone marrow

1. Measurement of a regenerative response – larger amount of polychromataphils
2. Use methylene blue- (one drop only) blood sits with blue for about 10 minutes, smear, air dry
3. Reticulocytes will have dark spots or lines in them- RNA, basophilic stippling
4. Count # reticulocytes/1000 RBC

Question 3

two types of reticulocytes in cats

Answer 3

a. Punctate: 2-8 basophilic stipples
b. Aggregate: Basophilic lines – more of the typical reticulocytes
c. Only count the aggregate ones

Question 4

Nucleated Red Blood Cells

Answer 4

1. CBC machine lyses everything without a nucleus (mature RBC, platelets)
2. If the RBC has a nucleus, it is not lysed, therefore counted as a WBC (artificially elevating WBC count)
3. But, we don’t know we have N-RBCs until differential
4. If N-RBC are seen on the differential, keep track of how many, record as #N-RBC/100 WBC
5. But then must correct the WBC count and absolute numbers on differential

Question 5

Corrected white blood cell count (math)

Answer 5

6. Observed WBC count (X) 100

100 + N-RBC

Question 6

Fibrinogen Levels

Answer 6

1. Fibrinogen levels increase during inflammation
2. Especially useful in dairy cattle for the early signs of mastitis
3. Can measure fibrinogen levels by heating plasma 56ºC.
   At 56ºC, fibrinogen pellets out (solidifiy), but other plasma proteins stay suspended

Question 7

Procedure for Fibrinogen Levels

Answer 7

1. Spin two hematocrits, measure one TP
2. Incubate other hematocrit in 56ºC water bath for 5 min
3. Respin heated hematocrit, measure TP
4. Fibrinogen level is the difference between the two numbers. Record as mg/dl

Question 8

Crossmatching

Answer 8

1. Used to determine compatibility for blood transfusions
2. Major and minor crossmatch
3. Looking for agglutination (RBC clumping) =indicates incompatibility
4. Can blood type cats via cards similar to humans. Dogs have 11 types of blood.

Question 9

Hematomas created by:

Answer 9

o Needle has passed through vein
o Bevel of needle is only partially in vein
o Insufficient pressure on venipuncture site after needle is withdrawn

Question 10

Blue Top Tube (BTT)

Answer 10

o Sodium citrate – blood clotting times

o Anticoagulant- that is reversible

Question 11

Gray Top Tube (GTT)

Answer 11

o Not used anymore
o Sodium Fluoride- binds with glucose
o Blood glucose

Question 12

Reference ranges

Answer 12

(i.e. normal values)
• Derived by measuring the blood chemistry components of clinically normal animals
• Vary w/ species, breed, sex, age, nutrition, geographic region

Question 13

Enzymes

Answer 13

accelerate reactions, and come out unchanged
• Proteins found inside cells that increase the rate of biochemical reactions
• Very low levels normally present in blood- should maintain an consistent level
o Increased levels usually seen if cells are damaged

Question 14

Measuring Enzymes

Answer 14

• Enzymes can not be measured directly but must be made to catalyze a chemical reaction whose product can be measured
Substrate + Enzyme–> *Product + Enzyme
*Must be a measurable product complex
• Enzyme concentrations are measured in international units (IU or U)–>amount of enzyme necessary to convert 1 micromole of substrate to product in one minute

Question 15

Factors influencing enzyme activity

Answer 15

o	Temperature
o	Dehydration
o	Ultraviolet light
o	pH extremes
o	Organic solvents
o	Heavy metal solvents

Question 16

Nomenclature of enzymes

Answer 16

o Enzyme names usually end w/ the suffix “-ase”

o The name may indicate its substrate or the type of chemical reaction it facilitates

Question 17

Liver

Answer 17

o Metabolism of carbohydrates, fats
o Synthesis of albumin, clotting factors
o Secretion of bilirubin
o Metabolism and elimination of toxins, drugs

Question 18

Enzymes associated w/ hepatocellular injury

Answer 18

o Alanine aminotransferase (ALT)
o Aspartate aminotransferase (AST)
 Sorbitol dehydrogenase

Question 19

ALT

Answer 19

o Alanine aminotransferase
Liver specific in dogs and cats
Not liver specific in horses, cattle, swine- elevation aren’t specially liver
Increased levels may also be due to drug administration (glucocorticoids, anticonvulsants)

Question 20

AST

Answer 20

o Aspartate aminotransferase
 Not liver specific
 Increased levels often seen w/ muscle inflammation, hemolysis of blood sample

Question 21

Sorbitol dehydrogenase

Answer 21

 Liver specific in all species

 Not routinely measured

Question 22

Enzymes associated w/ obstruction of bile flow

Answer 22

Alkaline phosphatase
GGT
Bilirubin
Bile Acids

Question 23

AlkPhos., AP

Answer 23

 Not liver specific
 Useful in dogs, cats
 Not useful in horses, cattle
 Increased levels often seen w/ bone injury, rapidly growing animals, use of glucocorticoids and anticonvulsants

Question 24

GGT

Answer 24

o Gamma glutamyltranspeptidase/glutamyltrans- ferase
 Liver is primary source
 Works well in small, large animal species
 Use of glucocorticoids and anticonvulsants may increase levels

Question 25

Bilirubin

Answer 25

 Derived from hemoglobin released by lysed RBC’s
 Increase levels associated w/ increased RBC destruction or liver disease
 Avoid exposure of blood sample to light
 Lipemia and hemolysis of blood sample may lead to falsely elevated readings

Question 26

Bile Acids

Answer 26

 Substance produced by the liver and secreted in bile to promote the digestion and absorption of fat from the small intestine
 Bile acids are reabsorbed from the SI and removed from circulation by the liver
 May be increased in portosystemic shunts, chronic liver disease

Question 27

Kidney Functions

Answer 27

o Eliminates metabolic wastes
o Maintains normal homeostasis (regulates electrolyte, essential organic molecule levels)
o Produces important hormones

Question 28

BUN

Answer 28

• Blood Urea Nitrogen
o Urea is a metabolic waste that results from amino acid breakdown
o Freely filtered at the glomerulus
 False positives may occur if animal ingests a high protein meal prior to test

Question 29

Azotemia may be due to:

Answer 29

o Increased BUN
 Prerenal Abnormalities
 Renal Abnormalities
 Postrenal Abnormalities

Question 30

Urea

Answer 30

a metabolic waste that results from amino acid breakdown

Question 31

Creatinine

Answer 31

o A nitrogen-containing molecule released from muscle at a constant rate
o Freely filtered by the kidney at a constant rate
o Increased levels are due to the same problems that lead to elevations in BUN

Question 32

The pancreas is an important gland involved in

Answer 32

o Digestion of food

o Regulation of blood glucose

Question 33

Digestive enzymes produced by the pancreas include

Answer 33

o Amylase
o Lipase
o Trypsin

Question 34

Amylase and Lipase

Answer 34

o Commonly measured in blood chemistry panels
o Found primarily in the pancreas but also found in other parts of the GI tract
o Increased levels associated w/ injury to pancreatic cells
 Elevations 3X’s the normal level considered significant

Question 35

Pancreatic Lipase Immunoreactivity (PLI)

Answer 35

o A highly specific test for pancreatitis in both dogs and cats
o Also used to diagnose exocrine pancreatic insufficiency (EPI)

Question 36

Trypsin

Answer 36

o Trypsin-Like Immunoreactivity (TLI)
o Increased levels associated w/ pancreatitis
o Decreased levels associated w/ exocrine pancreatic insufficiency (EPI)

Question 37

Glucose

Answer 37

o Utilized by body tissues for energy
o Blood glucose level reflects an equilibrium between
 The amount of glucose entering the bloodstream
 The amount of glucose leaving the bloodstream
o Glucagon and insulin help maintain normal blood glucose levels