Urine Lab Flashcards
Clean catch
to prevent germs from the penis or vagina from getting into a urine sample
- vagina : wipes to clean before hand and spread lips apart
- start peeing then then stop peeing
- pee in the sample cup until half full
- finish peeing in toilet
- > discared start and finish of pee
Urine collection
Best to take the 1st morning pee because the most concentrated but 2-3 hours is already fine
Sample should be analyzed in the following 1h otherwise detoriates at room temperature
Label container
Label the container with
-name -day of birth -Day collecting the sample -Time of collecting
Urine test
to assess metabolic and kidney disease
Direct examination for chemical analysis
5 min centrifugation at 400g, remove top part and stain the sediment for microscope analysis
centrifuge
machine that separates the liquid in the urine from solid components that may be present, such as blood cells, mineral crystals, or microorganisms. Any solid materials are then viewed under a microscope.
Physical analysis
Color and clarity assessed
Color: should be light yellow to light amber
Dark Amber/Red/Brown : pathology
Gree/Blue/etc : associated with food
Clarity: clear to slightly cloudy
assess by putting in front of a line or printed text
Cloudy or turbid: may be pathology
Chemical Analysis
Check opening date and expiration data + reaction time
Identifies substances, done with a dip stick
RBC concentration should be very low : below detection limit of the dip sticks -> too many can indicate inflammation or damage to uretha/kidney
too many WBC -> infection, inflammation urinary tract
crystals : normal
epithelium : normal in some quantity but if many then can be indicative of infection/inflammation urinary tract
microorganism : urine should be sterile, bacteria etc indicates infection of urinary tract/vagina
Sulfosalicylic acid precipitation test
Mix urine and observe turbidity: only clear urine used. If turbid, centrifuge it. Put in tube and with a film, mix well. Check against a black background. Rate degree of turbidity, if neg wait 10 min and check again.
Protein in the urine, proteinuria, is generally confirmed using a precipitation test. Protein is denatured in the presence of many substances and precipitates out of the urine. One of the most common reagents used is sulfosalicylic acid (SSA). This is added in urine. Neg to +4 : clear to opaque white
Density (osmality) test
teststrip
The test measures the urinary ion concentration
refractometer (looks like a handle)
exact measurement with refractive index. Put a drop in slide then look with one eye in the handle to see the value, make sure it is calibrated! Reference values:1.003-1.030 g/mL (possibly higher)
Calibrate refractometer
Looks like a handle with lid in front
- lifting up the daylight plate and placing 2-3 drops of distilled water then close plate
- wait 30sec for water to get room temperature
- Place your eye and hold towards natural light source
- If don’t see well the graduation adapt focus.
- Turn screw until white and blue filled meet at 0