Lab 6: examination of metabolic disorders Flashcards
Average TP content of the plasma?
60-80g/l
methods of measuring TP?
- Lowry method
- ultra-sensitive TP method
- Biuret test
- Refractometry
list the protein fractions?
- Albumin
- Globulin
- Fibrinogen
methods for testing albumin?
- measured using spectrometry
2. serum electrophoresis in combination with TP
causes of decreased albumin?
- 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
causes for albumin increase?
- Dehydration
methods for calculating globulins?
- roughly by the difference between albumin and TP
2. serum electrophoresis is used - TP concentration is needed
list the 5 classifications of globulins determined by electrophoresis?
- serum albumin
- Alpha-1- globulins
- Alpha-2- globulins
- Beta globulins
- Gamma globulins
what are the two most commonly used forms of electrophoresis?
- SDS page
2. isoelectric focusing (IEF)
what is the typical protein content in the plasma?
50% albumin
30% globulin
20% fibrinogen
what is the typical protein content in the serum?
60% albumin
40% globulins
what is polyclonal gammopathy?
- B and Gamma globulins derived from different clones
- generally occurs during inflammatory processes
what is monoclonal gammopathy?
- one protein fraction derived from one clone
- immune mediated or neoplastic conditions
describe what is seen and what can cause polyclonal gammopathy?
- broad based peak on the B and or gamma region
- causes include:
- chronic inflammation
- liver disease
- FIP
- occult heart worm disease
- Erlichiosis
describe what is seen in monoclonal gammopathy?
- sharp spike in the B or gamma regions
- peak can be compared to the albumin peak
- caused by both neoplastic and non-neoplastic disorders
what is a neoplasia causing monoclonal gammopathy?
- multiple myeloma
what is a non-neoplasic disorder causing monoclonal gammopathy?
- they are rare
- occult heartworm disease
- FIPV
- Erlichia canis
- lymphoplasmacytic enteritis
- lymphoplasmacytic dermatitis
what are the causes of hypoglobulinaemia?
- 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
methods of fibrinogen measurement?
- difference between plasma and serum TP
- based on the heat liable character of fibrinogen
- the test for thrombin time
causes of increased fibrinogen?
- acute inflammation
- dehydration
caused for decreased fibrinogen?
- 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)
methods of measuring glucose?
- hand held glucometer
- GOD/POD enzymatic method
explain why the glucose sample needs to be stored correctly?
- 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
causes for Hyperglycaemia?
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)
causes of hypoglycaemia?
- 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
glucose tolerance tests?
- intravenous tolerance test
- blood sampling every 15 minutes
- blood glucose should be normal after 30-60 minutes
- 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
- blood glucose should be twice the normal value after
when should we perform a glucose absorption test?
when we suspect:
- chronic bowel disease
- exocrine pancreatic deficiency
- can be used instead of IV glucose tolerance test
how do we test for acetone and acetoacetate?
by using the Ross reaction
- in the presence of ketones the test strip turns from white to purple
ratios of ketones in the milk, plasma and urine?
milk = 1mmol/l plasma= 3-5 mmol/l urine = 10mmol/l
how can we use urea analysis?
to determine the energy status of dairy cows
- high urea concentration indicated decreased carbohydrate intake
causes of hyperlipidaemia?
- 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
causes of hypolipodaemia?
- decreased intake (starvation)
- liver failure
- malabsorption, maldigestion
lipid absorption test?
- 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
Average cholesterol?
2-6 mmol/l
causes of hypocholesterolaemia?
- malnutrition
- liver failure (decreases synthesis)
- neoplastic disease
- hyperthyreosis (increased usage)
- decreased apolipoprotein syntheis
causes of hypercholesterolaemia?
- 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
