Urine Analysis

Urine Analysis
By:Diane C. Jette, Ph.D.
BioMedica Diagnostics Inc.


Reagent Test Strips
* Multiple test reagents on a ready to use test strip.
* Test results are read at different times after brief exposure to urine sample.
* The color on strip is compared to the reference color shown on test strip packaging.

Typical Test Strip Test
Glucose
Bilirubin
Ketone
Blood
Protein
Nitrite
Leukocytes
pH
Specific Gravity
Urobilinogen
Sensitivity_
* 4 to 7 mmol/L
* 7 to 14 mol/L
* 0.5 to 1.0 mmol/L (Acetoacetic acid)
* 150 to 620 g/L (Hemoglobin)
* 0.15 to 0.3 g/L (Albumin)
* 13 to 22 mol/L
* 5 to 15 cells/ L
* pH 5.0 to 8.5
* 1.000 to1.030
* 0.2 to 8 mol/L

Glucose
* Small amounts of glucose normally excreted by the kidney.
* Below sensitivity of the test.
* >6 mmol/L clinically significant.

Bilirubin
* Normally no Bilirubin is detected in urine.
* Even trace amounts are clinically significant.
Ketones
* Test detects acetoacetic acid in urine.
* Normal urine negative with this test.
* Detectable levels seen during physiological stress such as fasting, pregnancy, and frequent strenuous exercise.
* Large amounts with ketoacidosis due to starvation and abnormal carbohydrate or lipid metabolism.
Specific Gravity
* Range = 1.000 and 1.030
* Elevated specific gravity seen with elevated protein levels (1 to 7.5 g/L)

Blood
* Test measures hemoglobin and myoglobin.
* Trace amounts may be clinically significant.
* Often found in urine of menstruating females.
* False positives may be seen with urinary tract infections

pH
* Range from pH 5 to 8.5.
* False results may occur if excessive urine remains on the strip.

Protein
* Test sensitive to albumin.
* Negative result does not rule out the presence of hemoglobin or globulins.
* Normally no protein present in urine.
* Greater than 0.3 g/L is clinically significant.

Urobilinogen
* Normal Range in urine = 3 to 17 mol/L
* Greater than 34 mol/L transition from normal to abnormal.
* Total absence of urobilinogen cannot be determined with this test.
Nitrite
* Dependant on the conversion of dietary nitrate to nitrite by Gram Negative Bacteria.
* Positive results may indicate presence of greater than 105 cells per mL.
* Color not proportional to the number of cells.

Leukocytes
* Normally no leukocytes present in urine.
* Positive result is clinically significant.
* Some drugs interfere with the test

Urine Analysis.ppt