Lab 6: examination of metabolic disorders

Question 1

Average TP content of the plasma?

Answer 1

60-80g/l

Question 2

methods of measuring TP?

Answer 2

1. Lowry method
2. ultra-sensitive TP method
3. Biuret test
4. Refractometry

Question 3

list the protein fractions?

Answer 3

• Albumin
• Globulin
• Fibrinogen

Question 4

methods for testing albumin?

Answer 4

1. measured using spectrometry

2. serum electrophoresis in combination with TP

Question 5

causes of decreased albumin?

Answer 5

• decreased intake, decreased absorption
  
  • maldigestion, malabsorption
• decreases synthesis
  
  • liver failure
  • acute inflammation (negative acute phase proteins)
• increased utilisation
  
  • physiological conditions caused by mild changes
  • pregnancy, work, exercise, production (egg,milk etc)
    and chronic disease
• increased loss
  
  • via the kidneys (PLN)
  • via the GI (PLE)
  • skin (burns)
  • whole blood loss
  • sequestration into the body cavities
• other
  
  • hyperhydration

Question 6

causes for albumin increase?

Answer 6

• Dehydration

Question 7

methods for calculating globulins?

Answer 7

1. roughly by the difference between albumin and TP

2. serum electrophoresis is used - TP concentration is needed

Question 8

list the 5 classifications of globulins determined by electrophoresis?

Answer 8

1. serum albumin
2. Alpha-1- globulins
3. Alpha-2- globulins
4. Beta globulins
5. Gamma globulins

Question 9

what are the two most commonly used forms of electrophoresis?

Answer 9

1. SDS page

2. isoelectric focusing (IEF)

Question 10

what is the typical protein content in the plasma?

Answer 10

50% albumin
30% globulin
20% fibrinogen

Question 11

what is the typical protein content in the serum?

Answer 11

60% albumin

40% globulins

Question 12

what is polyclonal gammopathy?

Answer 12

• B and Gamma globulins derived from different clones

- generally occurs during inflammatory processes

Question 13

what is monoclonal gammopathy?

Answer 13

• one protein fraction derived from one clone

- immune mediated or neoplastic conditions

Question 14

describe what is seen and what can cause polyclonal gammopathy?

Answer 14

• broad based peak on the B and or gamma region
• causes include:
  
  • chronic inflammation
  • liver disease
  • FIP
  • occult heart worm disease
  • Erlichiosis

Question 15

describe what is seen in monoclonal gammopathy?

Answer 15

• sharp spike in the B or gamma regions
• peak can be compared to the albumin peak
• caused by both neoplastic and non-neoplastic disorders

Question 16

what is a neoplasia causing monoclonal gammopathy?

Answer 16

• multiple myeloma

Question 17

what is a non-neoplasic disorder causing monoclonal gammopathy?

Answer 17

• they are rare
• occult heartworm disease
• FIPV
• Erlichia canis
• lymphoplasmacytic enteritis
• lymphoplasmacytic dermatitis

Question 18

what are the causes of hypoglobulinaemia?

Answer 18

• reduced intake
  
  • neonates before drinking colostrum
  • absorption disorders of neonates
• decreases synthesis of globulins
  
  • acquired or inherited immunodeficiency
  • liver function impairment
• increased loss
  
  • PLN
  • PLE
  • Via skin (burns, inflammation)
  • bleeding

Question 19

methods of fibrinogen measurement?

Answer 19

1. difference between plasma and serum TP
2. based on the heat liable character of fibrinogen
3. the test for thrombin time

Question 20

causes of increased fibrinogen?

Answer 20

• acute inflammation

- dehydration

Question 21

caused for decreased fibrinogen?

Answer 21

• liver function impairment
• advanced protein deficiency
• DIC - overactive proteins - production of clots
• sequestration after bleeding into body cavities
• chronic bleeding
• blood loss
• inherited afibrinogenaemia (st Bernard dogs)

Question 22

methods of measuring glucose?

Answer 22

• hand held glucometer

- GOD/POD enzymatic method

Question 23

explain why the glucose sample needs to be stored correctly?

Answer 23

• plasma glucose is quickly catabolised by RBC enzymes
• to prevent this:
  
  • store sample cooled until measurement is taken
  • separate blood and plasma quickly
  • coagulate RBCs
    - 3% trichloric acid
  • take blood samples in tubes containing NaF - inhibits
    enolase in RBCs

Question 24

causes for Hyperglycaemia?

Answer 24

transient increase:

• Laboratory error (haemolysis, icterus etc)
• increased intake
• xylazin effect
• acute stress (especially cats >20mmol/l)
• after glucose infusion
• cranial trauma or inflammation (rabies, Aujesky disease)

constant increase:

• Diabets metitus
• cushing’s or glucocorticoid therapy
• progesterone effect (insulin resistance)
• enterotoxaemia (sheep)

Question 25

causes of hypoglycaemia?

Answer 25

- decreased energy status: - Ketosis - baby pig/puppy disease - starvation - strenuous exercise - laboratory error (improper storage) - anabolic steroid effect - insulinoma - insulin overdose (sometimes B blockers in heart insufficiency) - terminal liver failure - acute liver failure, glycogen deficiency - Addison's - septicaemia - hyperthyroidism - paraneoplasic syndrome

Question 26

glucose tolerance tests?

Answer 26

1. intravenous tolerance test - blood sampling every 15 minutes - blood glucose should be normal after 30-60 minutes 2. oral glucose tolerance test (glucose absorption test) - blood glucose should be twice the normal value after 30 minutes - blood glucose should return to normal after 120 minutes

Question 27

when should we perform a glucose absorption test?

Answer 27

when we suspect: - chronic bowel disease - exocrine pancreatic deficiency - can be used instead of IV glucose tolerance test

Question 28

how do we test for acetone and acetoacetate?

Answer 28

by using the Ross reaction | - in the presence of ketones the test strip turns from white to purple

Question 29

ratios of ketones in the milk, plasma and urine?

Answer 29

``` milk = 1mmol/l plasma= 3-5 mmol/l urine = 10mmol/l ```

Question 30

how can we use urea analysis?

Answer 30

to determine the energy status of dairy cows | - high urea concentration indicated decreased carbohydrate intake

Question 31

causes of hyperlipidaemia?

Answer 31

- hyperlipidaemia of ponies - increased fat content of diet - Diabetes mellitus - hypothyroidism - Addison's disease and glucocorticosteroid therapy - nephrotic syndrome - septicaemia - pancreatitis (lipase activation) - idiopathic - familiar hyperlipidaemia in minature schnauzers, beagles

Question 32

causes of hypolipodaemia?

Answer 32

- decreased intake (starvation) - liver failure - malabsorption, maldigestion

Question 33

lipid absorption test?

Answer 33

- to determine if there is existing malabsorption, maldigestion or where there is chronic bowel disease - test for plasma triglycerol levels (TG) - give corn oil per os - blood should be lipaemic and show a 2 fold increase in TG - if there is no such change the test should be repeated with pre-digested corn oil - increased TG and lipaemia we can suspect that the problem is pancreatic insufficiency - no change in TG and no lipaemia we can suspect interstitial absorption defect

Question 34

Average cholesterol?

Answer 34

2-6 mmol/l

Question 35

causes of hypocholesterolaemia?

Answer 35

- malnutrition - liver failure (decreases synthesis) - neoplastic disease - hyperthyreosis (increased usage) - decreased apolipoprotein syntheis

Question 36

causes of hypercholesterolaemia?

Answer 36

- increased dietary fat content - hypothyroidism - cushing's disease - Diabetes mellitus - nephrotic syndrome (concurrent low TP) - cholestatic diseases (increased leakage from liver due to bile duct obstruction) - idiopathic - primary dyslipidosis