Urinalysis - The Carter Center

• If it is difficult to deliver within 2 hrs, it is better to preserve
specimen in the refrigerator at the temperature between 2-6 0 C
or use chemical preservatives.
4. Centrifugation of the urine specimen
a) Mix the urine specimen
b) Transfer about 10 ml of urine in the centrifuge tube.
Balance tubes in the centrifuge.
c) Centrifuge the specimen at a medium speed (from 1500 –
2000 rpm) for 3-5 minutes
d) Discard the supernatant by quick inversion of the tube
e) Re suspend the sediment that is at the bottom of the tube,
by tapping the tube by your fingers
f) Take the sediment by Pasteur pipette from the tube and
transfer a drop into the clean, sterilized and dry slide. If
Pasteur pipette is not available, gently incline the tube and
place drop of sediment into the clean, sterilized and dry
slide.
g) Apply cover slide on the urine sediment that is on the slide.
This will make specimen to be spread on the slide on one
cell thickness.
h) Put the slide on the stage of microscope and tie it by clips on
the stage.
i) Lower the condenser, close the diaphragm and look under
10x objective of the microscope. Casts tend to concentrate
near the edge of cover slide.
j) Then after looking through at least 20 fields of the low power
objective, change the objective in to 40x objective. Do not
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