Urinalysis - The Carter Center

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Procedure:
1. Place 10 ml urine in a test tube. Allow warming to room temperature.
2. Add 1 ml Ehrlich's reagent and mix.
3. Let stand 3 to 5 minutes
4. Normal amounts of urobilinogen present in the urine sample will
change the solution to pink. Abnormally high amounts of urobilinogen
will change the solution to a Cherry red color. This must be reported
positive for urobilinogen.
Disregard any pink or light red coloration. This test is of no value in
infections of the Urinary tract because some bacteria produce nitrites,
which give false positive reaction. Formaline interferes with the test
and should not be used as a preservative.
Preparation of Ehrlich’s Reagent- see reagent number 7
B. Reagent Strip Tests for Urobilinogen- Urobilistix
The reagent strips have test areas for urobilinogen, which are based on
the Ehrlich's reaction in which p-dimethylaminobenzaldehyde reacts with
urobilinogen in a strongly acidic medium to form a colored aldehyde.
The reddish brown color that is formed varies with the amount of
urobilinogen present. After a timed interval, the color is compared with a
graded color chart. However, the test is not specific for urobilinogen and
reacts with substances know to react with Ehrlich's reagent.
Procedure:
1. Dip the reagent strip briefly into the specimen.
2. Remove excess urine by tapping the edge of the strip against the rim
of the urine Container.
3. Compare the color of the test area after 60 seconds with the color
chart supplied by the manufacturer.