NORMAL URINE COLOR
Clear/Colorless, Straw, Light/Pale Yellow, Yellow, Dark Yellow, Amber
Urochrome
pigment that causes the yellow color of urine
Uroerythrin
small quantity pink pigment contributes little to the color of normal, fresh urine
Urobilin
oxidation product of urobilinogen
Produces an orange-brown color in a urine that is NOT fresh
ABNORMAL URINE COLOR
Dark Yellow, Amber, Orange, Red, Pink, Blue, Green, Brown, Black
Yellow foam?
Indicates bilirubin
White foam?
indicates protein
Yellow- orange urine
Photo-oxidation (light) of large amounts of urobilinogen to urobilin
Yellow foam does NOT appear when shaken
Yellow- green urine color
Photo-oxidation of bilirubin
Red/Pink/Brown
Usually signifies presence of blood - range of pink to brown due to pH of urine, amount of blood, & length of contact
Hematuria
red & cloudy urine
Hemoglobinuria
red/clear urine with hemolyzed red plasma
Myoglobinuria
red/clear urine with clear plasma
Porphyrins
red appearing urine or often purple/port wine due to oxidation of porphobilinogen
Brown/Black urine color
oxidation of hemoglobin to methemoglobin
Fresh brown urine containing blood may indicate glomerular bleeding
Blue/green
Typically, from a UTI caused by Pseudomonas species (aeruginosa)
Clarity
Normal = Clear (0), Hazy (1+),
Slightly Cloudy (2+), Cloudy (3+), Turbid (4+)
Specific Gravity
The density of a solution compared with the density of a similar volume of distilled H2O at a similar temperature
Specific gravity of urine is a measure of the density of the dissolved chemicals in the specimen
Normal = 1.002 – 1.035
Osmolality
Measured with an Osmometer
Osmolarity is a more representative of renal concentrating ability
Refractometer
Refractometry – determines the concentration of dissolved particles in a specimen by measuring the refractive index
