Color Chart. This is a specially prepared multitest
strip that is simply dipped into the urine specimen
and then compared with the color values for the
various tests on the accompanying chart. The
color chart indicates pH values, and the numerical
value should be reported.
The specific gravity of the specimen is the
weight of the specimen as compared to an equal
volume of distilled water. The specific gravity
varies directly with the amount of solids dissolved
in the urine and normally is from 1.015 to 1.030
during a 24-hour period.
The first morning specimen of urine is more
concentrated and will have a higher specific grav-
ity than a specimen passed during the day. A high
fluid intake may reduce the specific gravity to
below 1.010. In disease the specific gravity of a
24-hour specimen may vary from as low as 1.001
to as high as 1.060.
The specific gravity may be measured with the
urinometer or the index refractometer, available
as standard equipment at most duty stations. The
refractometer may be held manually (fig. 6-11)
or mounted on a stand like a microscope. The
specific gravity is determined by the index of light
refraction through solid material.
Measurement with Urinometer
Pour urine into the cylinder until it reaches
a point approximately 1 1/2 inches below
the top of the cylinder. Insert the
urinometer, making sure that it is floating
freely. The cylinder should not overflow
when the urinometer is immersed. Read the
bottom of the meniscus.
If the specimen is cloudy, the urine should
be centrifuged before specific gravity
readings are taken. Cloudy urine tends to
show low (and invalid) specific gravity.
Measurement with Index Refractometer
Hold the index refractometer in one hand,
and with the other hand and two applicator
sticks, place a drop of urine on the glass
section beneath the coverglass.
Hold the refractometer so that the light
reflects on the glass section and look into
the ocular end. Read the number that ap-
pears where the light and dark lines meet.
This is the specific gratity.
Glucosuria is the presence of an abnormal
amount of glucose in the urine. Traces of sugar
are often found in normal urine, but are not
enough to react to any of the routine tests for
glucose. However, different sugars in the urine
are of various clinical significance. When per-
forming routine urinalysis, we can test for glucose,
and any trace of glucose in the test suggests that
something is wrong with the patients car-
Methods for Measuring Glucose
1. Test Strip, Glucose and Blood. This test is
specific for glucose. Other sugars do not
Remove strip from container.
Dip into specimen. Remove and wait 30
Immediately compare the test strip
against the color chart.
Record results. Normal urine is negative
If there is a positive reaction for
glucose, a Clinitest is done for both con-
firmation and quantitation.
2. Urine-Sugar Test Tablets (Clinitest Tablets)
Figure 6-11.Index refractometer.
Place 5 drops of urine in a large test
Add 10 drops of water and mix well.
Add one Clinitest tablet.
Put the tube in a rack. Let stand until
the reaction is completed (foaming ac-
tion has stopped).
Compare the color with the color chart
and record the results.
If an orange color appears and then
disappears, run the test again, diluted
Be careful not to touch the end of the
tube as it is extremely hot.