Flashcards
BIOCHEMISTRY 3 + 4 + 5
Cards in this deck (116)
- 1What are the major sources of glucose ?dDietary absorption
Liver production :
Glycogenolysis
Gluconeogenesis - 2What promotes glycogenolysis?Catecholamines
Glucagon - 3What promotes gluconeogenesis?Corticosteroids
Glucagon
Growth hormone - 4What should blood be collected in if the sample can't be analysed in clinic?Fluoride oxalate
- 5What is the normal reference interval in monogastric animals?4-6mmol/L
- 6What may cause transient hyperglycaemia ?Adrenalin release due to fear/excitment?
- 7What may hypoglycaemia be caused by?Excessive use
Reduced hepatic storage
Insufficient dietro intake
Excessive insulin or analogues
Lack of corticosteroids - 8What may cause excessive use of glucose?Sepsis
Neoplasia
Excessive physical exertion - 9What may cause reduced hepatic storage of glucose?Advanced liver disease
Sepsis - 10When might animals have an insufficient dietary intake of glucose?Neonates and small dogs
Starvation
Malabsorption and malnutrition - 11What may cause excessive insulin/ analogues?Insulinoma
Iatrogenic insulin overdose
Paraneoplastic - 12What may cause a lack of corticosteroids ?Hypoadrenocorticism
- 13What may cause hyperglycaemia?After a meal (transient)
Catehecholamines (usually transient)
Iatrogenic (exogenous glucose administration )
Insulin antagonism
Diabetes mellitus
Stress - 14What may cause insulin antagonism ?Endogenous /exogenous steroids
- 15What serum glucose concentrations can cause glucosuria?10mmol/l -Digs
16.6mmol/L cats - 16Why might we want to test persistence of glucose alterations ?To confirm persistanent hyperglycaemia and diabetes mellitus
To monitor response to treatment and tailor insulin - 17What tests can we do to test persistence of glucose alterations?Glucose curve
Glycated proteins - 18What creates glaciated proteins?Glucose reacts non-enzymicatically and irreversibly with amino groups on all proteins in a slow process to give glaciated proteins
- 19What is fructosamine?Irreversibly glycated albumin
It is high when glucose concentration is high and has been for the previous 1-3wks - 20What affects fructosamine ? What causes altered turnover of fructosamine ?Affected by albumin / protein concentration
Hyper/Hypothyroidism cause altered rate of protein turnover - 21What controls sodium concentration?Thirst
RAAS
ADH release - 22What alters sodium concentrationLoss of water
Loss of sodium and water (volume depletion) - 23What may cause hyponatraemia?Loss of Na
Water retention or fluid overload - 24How may Na be lost ?GI- vomiting, diarrhoea
Kidneys - reduced tubular function, lack of aldosterone, increased diuresis
Skin - burns, sweat
3rd space - 25What may cause water retention or fluid overload?Oedematous disorders
Innapropriate ADH secretion - 26What may cause hypernatraemia ?Water loss in excess of sodium
-Free water loss
-Hypotonic fluid loss - 27How may free water loss occur?Inadequate water intake
Lack of ADH
Fever, panting - 28How may Hypotonic fluid loss occur?GI
Kidney - osmotic diuresis - 29How does Na concentration affect Cl concentration?Na and Cl concentrations tend to follow each other i.e. if Na is high Cl is also high
If this is not the case something is very wrong! - 30When is hypochloridaemia seen without hyponatraemia?Vomiting of pure stomach contents
- 31What causes hyperkalaemia?Increased intake
Reduced renal excretion
Movement out of cells - 32What causes hypokalaemia ?Reduced intake
Renal losses
GI losses
Movement into cells - 33What regulates calcium and phosphorous levels?Parathyroid hormone (PTH)
Calcitonin
Vitamin D3 (calictriol) - 34How does PTH affect Ca and Phosphate?Increased PTH causes Hypercalcaemia and Hypophosphataemia
- 35How does vitamin D affect Ca and P?Hypevraminosis D causes hypecalcaemia and hyperphosphateaemia
- 36Is all calcium affected by PTH?No
Only the free Ca - 37What affects total calcium?Albumin
- 38What do we use urea and creatinine levels to asses?Renal function
- 39What is azotemia ?Raised levels of creatinine and urea
- 40Are urea and creatine sensitive markers of renal function?No, they are insensitive markers
Azotemia only becomes apparent when >75% of functional nephrons are lost - 41What may cause and increase in urea ?Decreased GFR due to any cause (pre renal, renal, post renal)
GI haemorrhage
High protein diet (mild)
Recent meal (mild)
Catabolism - fever - 42What may cause a decrease in Urea?Reduced production by the liver
Low protein diet
Aggressive fluid therapy
Deficiency of enzymes of the urea cycle - 43What may cause an increase of creatinine ?Decreased GFR due to any cause
High muscle mass (breed) - 44What may cause a decrease in creatinine ?Reduced muscle mass
Usually not clinically significance - 45Types of azotaemia Pre renalCaused by: Dehydration or decreased CO
Increased production
Detection: V concentrated urine
Other clinical evidence
Should respond to fluid therapy - 46Types of azotaemia RenalCaused by: Decreased functional nephrons
Detection: Inadequately concentrated urine
Doesn't resolve with fluid therapy - 47Types of azotaemia Post renalCaused by: Urine leakage (+reabsorption)
Blockage resulting in decreased excretion
Detection: Clinical evidence
Often hyperkalaemia - 48What else do we use to asses kidney function?USG
- 49What extra renal things may affect kidney function?ADH action and release- decreased sensitivity to ADH in hypercalcaemia + hypokalaemia, endotoxemia
Medullary concentration gradient
Osmotic forces (gucosuria)
Therapies
Behavioural or metabolic (PD) - 50What does can urinalysis tell us?UTI
Neoplasia
UTD
Hyperglycaemia - DM
Hypoproteinema - PLN - 51What tests do we need to do in urinalysis?Sample collection
Gross examination
USG
Dipstick (biochemistry)
Sediment examination - 52Voided/free catch sampling Where in the urine stream should you sample? When is it useful?Should be midstream
Useful if pigmenturia - 53Cather sampling When do we use Cather samplingUse as a therapeutic procedure
When you suspect bladder/urethral cancer to increase the chance of collecting cells to analyse at microscopy - 54Cystocentesis sampling BenefitsMinimises risk of contamination
Preferred method for urine culture - 55Why do we need to analyse urine rapidly ?Cells disntegrate
CO2 evaporates which raises pH
Crystals form
Bilirubin, urobilinogen and casts break down
Bacteria grow or die - 56What can colour of urine tell us?Pale yellow to amber = normal
Red to red brown = haematuria, haemoglobinuria, myoglobinuria
Dark yellow/brown/green = bilirubinuria - 57How can we differentiate haematuria from pigmenturia?Haematuria (RBCs):
Red, cloudy urine
Clears on centrifugation
Erythrocytes in sediment
Pigmenturia (Hgb/Mgb):
Red to brown urine
Doesn't clear on centrifugation of urine
No erythrocytes in sediment - 58What is myoglobin?Haemeprotein which transports and stores oxygen within muscles
Released from muscle when theres membrane damage
Readily passes into urine - 59How does the dipstick distinguish between myoglobin, free haemoglobin and RBCRBC?It can't!
- 60Myoglobinuria v Hemoglobinuria MyoglobinuriaUrine red-brown
After centrifugation ->clear plasma
Doesn't stay in circulation
Urine red but plasma clear
Elevated CK and/or AST - 61Myoglobinuria v Hemoglobinuria HaemoglobinuriaUrine red-brown
After centrifugation ->pink/red plasma
Stays in circulation
Urine red and plasma red
Decreased PCV/HCT - 62What could cloudiness of urine suggest?Increased cellular elements
Crystalluria
Bacteria
Lipids
Mucus
Casts
Sperm
Precipitation of salts - 63What may cause an overestimation in USG?USG?Marked glycosuria and marked proteinuria
- 64What does USG tell us ?Concentrating ability
- 65What is more sensitive in measuring concentrating ability of the bladder, USG or azotaemia?USG (only slightly)
- 66Appropriate USGConcentrated
>1.030 (dogs)
>1.035 (cats)
Some concentrating ability
1.015-1.030 (dogs)
1.015-1.035 (cats) - 67What is isothenuria ?Urine has the same osmolarity as plasma
1.008-1.012 - 68What is Hyposthenuira?Very low USG, suggests active effort by the kidney
<1.008 - 69What do we need to disregard for dipstick analysis?Leucocytes
Nitrite
USG - 70What may acidic urine suggest ?Meat diet
Protein catabolic state
Acidifying agents
Metabolic / respiratory acidosis
Bacterial contamination - 71What is normal pH for dogs and cats?5-7.5
- 72Alkaline urineCereal diet
UTI w urease +ve organisms
Old samples /exposed to air
Metabolic or respiratory alkalosis
Post-prandial alkaline tide - 73How much protein is normal in the urine?Small amounts of urine (up to 1+)
However must be interpreted light of USG - 74When might you get a false positive with protein dipstick?With alkaline urine
- 75When is protein increased in the urine?Inflammation or haemorrhage of LUT
If there is significant haematuria
Protein loss from kidney - 76When is glucose found in the urine?When serum glucose is above 10mmol/l (dogs) and 16.6 (cats)
Fanconi's syndrome (when serum glucose is normal- failure of resorption by tubules) - 77Are ketones normally found in the urine ?Nope
- 78When are ketones found in the urine?Result of exaggerated, incomplete oxidation of fatty acids
Diabetes mellitus
Negative energy balance - 79How good are dipsticks at detecting blood in urine?Very sensitive but don't differentiate well
Erythrocytes (Spotting)
Haemoglobin (Diffuse colour change)
Myoglobin - 80How is bilirubin conjugated in urine?Only conjugated bilirubin in urine
- 81What are the causes of bilirubinurea ?Haemolysis
Liver disease
Biliary obstruction - 82What is a normal amount of bilirubin in the urine ?Up to +2 may be normal in a dog (male esp) in concentrated urine
- 83Describe how you would perform a sediment analysisCentrifuge 1ml of urine (1000-1500 rpm for 3 mins)
Decant and re-suspend pellet
Place a drop on top of a glass slide and coverslip - 84Is RBC normal in urine sediment analysis?Occasional RBC normal - depends on method of selection
<5 per hpf - 85Is WBC normal in urine sediment analysis ?Occasional WBC normal
<5 per hpf
Increased WBC indicate inflammation in the urinary tract - 86Are epithelial cells normal in urine sediment analysis?Small numbers of squamous and transitional epithelial cells are normal
Increased in UTI, Irritation, Neoplasia - 87What are casts ? Are they a normal finding?Cyndrical moulds of tubules composed of mucoproteins +/- cells
Occasional hyaline and granular casts may be normal
Granular, cellular and waxy indicate tubular damage - 88Are crystals a normal finding in urine?Crystals detected in fresh urine likely formed in vitro
Crystals can precipitate in stored urine after collection
Crystalluria should be interpreted w USG - 89—Struvite crystals
Magnesium ammonium phosphate - 90Significance of struvite crystals ??UTI
Urolithiasis
Could be normal - 91—Amorphous
Urate - acidic pH
Phosphate - alkaline pH
No clin significance
- 92—Calcium oxalate dihydrate
Can be normal
- 93—Calcium oxalate monohydrate
- 94Clinical significance of calcium oxalate monohydrateHyperoxaluric disorders or Hypercalciuria due to ethylene glycol toxicoxis
Ingestion of oxalate rich foods - 95—Ammonium birurate / uric acid
- 96Ammonium birurate / uric acid significancePortosystemic shunts
Liver disease - 97—Cystine
- 98Cystine clinical significanceAssociated w metabolic defect in tubular reabsorption of cystine
- 99—Cholesterol
- 100—Bilirubin
- 101—Drug metabolites
- 102Significance of increased activity of enzymesCell damage
Impairment of enzyme clearance
Physiological
Induction
Artefactual - 103What do we measure when assessing enzymes ?Enzyme activity
- 104Properties of diagnostically useful enzymesHigh sensitivity
Specific for one tissue
Be readily assayed in the lab and stable in the sample
Be cleared from plasma at a rate appropriate to the diagnostic test
Show clear separation between normal and pathological values - 105What enzymes suggest muscle damageCK - Creatine Kinase
AST - Asparate aminotransferase
LDH - Lactate dehydrogenase
Leak from muscles cells due to : degeneration, necrosis, inflammation - 106What is CK?Makes ATP available for muscle contraction
Catalyses the production of high energy ATP via transfer of a phosphate bond from creatine phosphate to ADP - 107What is creatinine?A waste product made from spontaneous breakdown of creatine at a constant rate at a constant rate and eliminated via the kidneys
- 108When is creatinine increased after awn injury ? When does it return to normalIncreases rapidly post injury (6-12h)
Returns to normal (1-2d with single injury)
NB if there it is increased persistently there is ongoing damage - 109What can increased CK suggest ?Muscle injury :
Degenerative
Metabolic
Neoplasia that damages the membrane
Nutritional
Inflammatory / infectious -Myostisis
Toxic
Trauma - 110Degeneratice muscle injuryHypoxia:
Seizure
Saddle thrombus
Exertional rhabdomyolysis
Prolonged recumbancy - 111Metabolic muscle injuryHypothyroidism
- 112Nutritional muscle injuryAnorexia
Decrease in vit E/selenium - 113Toxic muscle injuryMonensin
Castor bean - 114Traumatic muscle injurySeizures
Exertion
IM injections
Restraint
Post surgery - 115What may cause a false increased CK?Haemolysis
Hyperbilirubinaemia
Lipemia - 116—
Information
- Description
- Vet Med 2 Flashcards on BIOCHEMISTRY 3 + 4 + 5, created by Alice Butterworth on 20/05/2019.
- Created by
- Alice Butterworth
- Views
- 1
- Rating