1Identify the parameters read at 30 seconds, their principles, and positive colors:
Glucose: Double sequential enzyme reaction, Green to brown (KI chromogen, Bilirubin: Diazo reaction, Tan or pink to violet.
2Identify the parameter read at 40 seconds, its principle, and positive color:
Ketones: Sodium nitroprusside reaction, Purple.
3Identify the parameter read at 45 seconds, its principle, and positive color:
Specific gravity: pKa change of polyelectrolyte, Blue (1.000) to yellow (1.030).
4Identify the parameter read at 120 seconds, its principle, and positive color:
Leukocytes: Leukocyte esterase, Purple.
5Identify the parameters read at 60 seconds, their principles, and positive colors:
Protein: Protein error of indicators, Blue-green, pH: Double indicator system, Orange (pH 5.0) to blue (pH 9.0), Blood: Pseudoperoxidase activity of hemoglobin, Uniform greenlue (Hgb/Mb), Speckled/spotted (intact RBCs), Urobilinogen: Ehrlich reaction, Red, Nitrite: Greiss reaction, Uniform pink.
6Identify the sequential steps of the Reagent Strip Technique:
Dip the reagent strip briefly (no longer than 1 second) into a well-mixed uncentrifuged urine specimen at room temperature, remove excess urine by touching the edge of the strip to the container as it is withdrawn, blot the edge of the strip on a disposable absorbent pad, wait the specified amount of time for the reaction to occur, and compare the color reaction of the strip pads to the manufacturer's color chart in good lighting.
7What is the principle of Automated Reagent Strip Readers?
Reflectance Photometry.
8Explain the mechanism of Reflectance Photometry:
Light reflection from the test pads decreases in proportion to the intensity of color produced by the concentration of the test substance; the darker the color of the reagent pad, the lesser the light reflection (and vice versa)
9Define Specific Gravity:
A measure of the amount of dissolved substances in a solution, comparing the density of a solution with the density of an equal volume of distilled water at a similar temperature (influenced by both the number and size of particles in a solution).
10Identify the standard reference ranges for Specific Gravity
11What is the significance of a Specific Gravity reading of <1.003?
Not a urine specimen (except in Diabetes Insipidus). Note: 1.001 represents pure water.
12What is the significance of a Specific Gravity reading of >1.040?
Radiographic dye is present in the specimen.
13SG of Isosthenuria
Fixed Specific Gravity equal to 1.010.
14SG of Hyposthenuria
Specific Gravity <1.010.
15SG of Hypersthenuria
Specific Gravity >1.010.
16What is the standard calibration temperature for a Urinometer?
20 degree celsius
17State the rules for Urinometer Temperature Correction:
-0.001 for every 3 degree celsius that the specimen temperature is below the calibration temperature, and add 0.001 for every 3 degree celsius that the specimen temperature is above the calibration temperature.
18State the rules for Urinometer Solute Correction (Glucose and Protein):
-0.004 for every 1 g/dL of Glucose present, and -0.003 for every 1 g/dL of Protein present.
19What is the volume of urine required for Urinometry?
10 to 15 mL.
20Describe the Calibration of a Urinometer:
Uses Potassium sulfate (K_2SO_4) solution (20.29 g K_2SO_4 to 1 LH_2O), with an expected S.G. reading of 1.015.
21Describe the proper technique for taking a Urinometer reading:
Pour an adequate amount of urine into a proper-sized container, add the urinometer with a spinning motion, and take the scale reading at the bottom of the urine meniscus.