the macroscopic exam Flashcards
what are the 4 parameters considered in a macroscopic exam?
- colour
- transparency
- odour
- specific gravity
what is normal urine color
light/plale yellow
- medium yellow
- amber or dark yellow
which pigments give urine its colour?
- urochrome (major pigment)
- urobilin
- uroerythrin
cause of pale yellow, yellow, or amber urine
- normal urochromes and urobilin
cause of deep yellow urine
- highly concentrated urine
- quinicine (Aabrine)-following acidification
- phenacetin
- nitrofurantoin
- riboflavin (large quantities)
causes of blue urine
- methylene blue
- indigo carmine and indigo blue dye
- indicans
- pseudomonas sp. infections
causes of green urine
- (mixture of blue and yellow)
- methylene blue
- dithiazinanine iodine (Dizan)
- indigo blue dye
- evans blue
- biliverdin
- riboflavin
- thymol
causes of orange-yellow urine
- highly concentrated urine
- excess urobili
- bilirubin
- pyrium
- phenazopyridine
- salicylazosulfapyridine (Azulfadine)
- fluorescein sodium
causes of red, pink, red-brown, red-orange, and orange urine
- hematuria
- hemaglobinurea
- myoglobinurea (red-brown)
- porphyrinuria
- congo red
- phenosulfonphthalein (following alkanization)
- neoprontsil
- warfrin (orange)
- rhubarb
- carbon tetrachloride
- phenazopyridine
- phenothiazines
- diphenylhydantoin
- pseudomonas
causes of brown urine
- methemoglobin
- melanon
- salicylazosufapyridine
- nitrofurantoin
- phenacetin
- sulfonamides
- bismuth
- mercury
causes of yello-brown urine
- bile pigments
causes of brown to black (brown or red) urine
- melanin
- methemoglobin
- myoglobin
- bile pigments
- thymol
- phenolic compounds
- nitrofurantoin
- naphthalene
- chlorinated hydrocarbons
- aniline dyes
- homogentisic acid
what causes dilute urine
dilute urine
causes of milky white urine
- chyle
- pus
- phosphate crystals
what food commonly alter urine colour
- food dyes
- riboflavin
- carrots
- rhubarb
- beets
if hemoglobin or myoglobin is in the urine, after centrifuging, what will happen to the colour of the supernate?
nothing
what is the most common cause of urine turbidity?
- crystals
what is the solubility of most crystals influenced by?
temperature
What can influence the solubility of crystals?
pH
describe the color and transparency of hematuria
red-brown (sometimes black)
turbid
describe the color and transparency of hemoglobinuria
red-brown (sometimes black)
transparent
what terms are used to describe urine transparency
- clear
- cloudy
- turbid
- floculent
which species normally have cloudy urine? And why?
- horses
- rabbits
- guinea pig
- goats
due to: calcium carbonate crystals
what do horses have increased amounts of in their urine resulting in more turbid urine?
mucus
what is the typical cause of flocculence?
- aggregates of WBCs
- clumps of epithelial cells
- small urinary calculi
does normal urine odor vary between species and sex?
yes
what terms are used to describe the odour of urine?
- aromatic (normal)
- strong (also normal)
- ammonia (caused by ureas-producing bacteria)
- putrid (caused by bacterial degradation of a large quantity of protein)
- fruity/acetone (an abnormal odor caused by the presence of ketones in the urine (diabetic))
what causes the ammonia odor of urine
urease producing bacteria
what causes the putrid odor of urine
bacterial degradation of a large quantity of protein
what causes the acetone/acetone odor of urine
- the presence of ketones (diabetic)
what is specific gravity a measurement of?
- the density of urine compared to pure water at the same temperature
- a weight comparison
- The specific gravity of water is 1.000
what influences specific gravity?
- number of solute particles
- molecular size of the solute
- molecular weight of the solute
- different solutes have their own characteristic effect on specific gravity
- temperature (density decreases as temperature increases)
why should specific gravity be interprited with each urinalysis?
1.- clarifies the interpretation of the urinalysis results
- provides data regarding the ratio of solutes to solvent
- urinalyses are typically runs using a small sample without regard for the rate of formation and knowing the specific gravity allows for semi-quantitative interpretation
- to assess the ability of the renal tubules to concentrate or dilute the glomerular filtrate
- depends on the quantity and weight and quantity of dissolved particles
- is the only actual test for renal function in a routine urinalysis
- to assess the ability of the renal tubules to concentrate or dilute the glomerular filtrate
normally a pale urine sample will have a ____________ specific gravity
low
normally a dark urine sample will have a ____________ specific gravity
high
after 12h fast, normal canine specific gravity is __________
> 1.025
after 12h fast, normal canine cat specific gravity is __________
> 1.035
what is specific gravity not affected by?
suspended particles
