Urinalysis
Veterinary Assistant Program
Middlesex Community College
Michael Lavoie
12/17/12
Body Tube
Ocular lens
(Eyepiece)
Nosepiece
Arm
Objectives
Stage
Stage Clips
Coarse Adjustment
Diaphragm
Light
Fine Adjustment
Base
Always carry a microscope with one hand holding the arm
and one hand under the base.
What’s my power?
To calculate the power of magnification, multiply the power of the ocular lens by the
power of the objective.
What are the powers of magnification
for each of
the objectives we have on our
microscopes?
Fill in the table on
your worksheet.
Comparing Powers of Magnification
We can see better details with higher the powers of
magnification, but we cannot see as much of the image.
Which of these images would be
viewed at a higher power of
magnification?
How to make a wet-mount slide …
1 – Get a clean slide and coverslip from your teacher.
2 – Place ONE drop of water in the middle of the slide. Don’t use too much or the
water will run off the edge and make a mess!
3 – Place the edge of the cover slip on one side of the water drop.
4 - Slowly lower the cover slip on top of the drop.
Cover
Slip
Lower slowly
5 – Place the slide on the stage and view it first with the red-banded objective. Once you
see the image, you can rotate the nosepiece to view the slide with the different objectives.
Always carry with 2 hands
 Only use lens paper for cleaning
 Do not force knobs
 Always store covered
 Keep objects clear of desk and cords
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Place the Slide on the
Microscope
Use Stage Clips
Click Nosepiece to the
lowest (shortest) setting
Look into the Eyepiece
Use the Coarse Focus
Follow steps to focus using low power
 Click the nosepiece to the longest
objective
 Do NOT use the Coarse Focusing Knob
 Use the Fine Focus Knob to bring the
slide
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Visual Urine Attributes
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Volume
color
turbidity
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It is ideal to standardize the volume of urine from
which the urine sediment is prepared.
◦ In human medicine, 10 ml of urine is used as the standard
volume.

This is difficult to accomplish in many animals,
particularly small patients, hence we try and
standardize the urine volume from which the
urinalysis is performed (regardless of the volume
received) to 3 ml
Urine volume affects the results of the
urine sediment examination, because the
semi-quantitative results of the sediment
are derived from the standard urine
volume and will differ between urine
collections of different volumes.
 Observations of color and turbidity are
made on the well-mixed urine specimen.

Specific Gravity
This is a measure of the urine
concentrating ability of the animal.
 The specific gravity should be read on the
refractometer using the urine
supernatant.
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Dip Stick Anaylsis
Dipsticks consist of various pads
containing chemical ingredients which
provide a color change when a particular
analyte is present in urine.
 This color change is converted to a semiquantitative result for the analyte in
question.
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In animals, the dipstick is used to give results
for pH, protein, glucose, ketones, bilirubin
and proteins containing a heme group
(blood)
There are also dipstick pads for urine
specific gravity, nitrate, leukocytes and
urobilinogen on commercially available
dipsticks.
◦ These are either not accurate in animals or do
not provide much additional information in
animals and are seldom reported.
Sediment Examination
For this examination, the standard volume
of urine is centrifuged in a low speed
centrifuge.
 The supernatant is removed and the urine
is gently resuspended in a standard
volume (0.5 ml) of urine supernatant.
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A drop of the resuspended urine is placed
on a slide, coverslipped and examined
under a light microscope using the 10x
and 40x objectives.
 This looks for crystals, bacteria, blood etc.
 To examine do the following:
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Low Magnification
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Examine the entire coverslip using the
10x objective.
◦ At this magnification, casts, large crystals,
debris, parasitic ova are semi-quantified.
High Magnification
Specific structures identified at low
magnification (e.g. casts) and several
random fields are examined using the 40x
(high dry) objective.
 At this higher magnification, leukocytes,
erythrocytes, epithelial cells, fat droplets,
small crystals, sperm, debris and bacteria
are semi-quantified.
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for information on the performance and meaning of
the test.
Indications for Urine Collection
Diagnostic, (urinalysis, radiographic
procedures),
 Therapeutic (urethral blockage, inability
to urinate)
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Methods of Collecting Voided
Samples
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Voided: Easiest method, no special
knowledge or special skill needed.
1) Technique: The urine caught during
normal urination in mid-stream in a clean or
sterile container.
2) Problems: These samples are considered
non-sterile and are often contaminated with
bacteria and cells from the lower urinary
tract.
◦ If this method is used for an UA (urine analysis) it
should be noted on lab report.
Manual Expression of the Bladder

This method is often used in patients unable to
urinate such as neurological and spinal patients.
1) Technique: The patient can be standing, or in
lateral recumbency.
◦ One person might need to restrain patient and
another express the bladder depending upon the
patient.
◦ Locate bladder via palpation and apply gentle, steady
pressure with hand(s) to push urine out of bladder.
◦ With steady pressure resistance and inhibitory
reflexes of sphincter muscles should be overcome.
Complications
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2) Possible problems: Trauma to or rupture of
bladder
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This method also produces a "contaminated" sample,
usually unsuitable for an accurate UA.
Catheritization
1) General information:
a) This method can be used in both
sexes and most species, but is more
difficult in females and as the patient gets
smaller.
b) It is essential to maintain sterility
and avoid iatrogenic infection.
c) Catheters should be lubricated
before insertion with sterile gel.
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d) Long hair in the urethral area can be clipped
and the urethral area is cleaned with sterile water
to avoid contamination
e) The correct size catheter is important to
avoid kinking, urine leakage (too small) or causing
trauma to the urethra (too large).
f) Pre-measure (estimate) the distance to
the bladder. A catheter inserted too far into the
bladder can cause trauma and hematuria or even
turn on itself and become blocked, or tie itself
into a knot, which makes it REALLY hard to
remove!
Male Dog Catheterization
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Instruments:
◦ Sterile plastic semi-flexible catheter or soft
red rubber feeding tube and syringe or
container to collect urine.
 If the catheter is too flexible or too small it can be
difficult to place.
◦ Catheter size is expressed in "French" units
(Fr), the smaller number indicates a smaller
diameter catheter.
Technique
Two or more people may be needed depending on
patient, usually done in standing or lateral position
(unless anesthetized).
 The assistant exteriorizes the penis and it is gently
cleansed with sterile water or very mild disinfectant.
 The catheter is handled in a sterile manner (with gloved
hands or using the finger tab technique - to be
demonstrated in lab).
 The catheter tip is lubricated with sterile jelly. The
catheter tip is inserted into the penile orifice and is
threaded up the urethra into the bladder.
 The catheter may be blocked or meet resistance at 2-3
points.
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If this happens rotate it and increase pressure slightly.
Possible problems
:Trauma to urethra or lining of the
bladder.
 Infection if nonsterile catheter is used.
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Indwelling Catheters
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Depending upon the situation the catheter
may be sutured in place for a period of time
to allow the constant drainage of urine and
prevent re-blockage.
◦ Usually a UCS (Urinary Collection System) is
used
These cats should be maintained on a grate,
as they will rapidly soil blankets or towels in
their cages.
 In cats do not allow them to use a litter pan,
and litter can work its way up the catheter
into the bladder.
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Female Dog Catheterization
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It is much more difficult to catheterize
females because of the internal position
of the urethra, often cystocentesis is the
preferred method of collection of a
sterile sample for this reason.
a) Equipment: Rigid metal catheter,
semi-rigid plastic catheter, Foley catheter,
vaginal or nasal speculum, otoscope, etc.
Techniques
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The bitch is restrained in the standing
position if not under anesthesia, or the
catheter can be placed in V/D or D/V
position if under anesthesia.
The vulva is cleansed with sterile solution or
mild disinfectant and the sterile catheter is
handled with gloved hands.
There are several placement techniques:
◦ Visual: A speculum (lubricated with sterile gel)
with a light source is used to dilate the vagina and
locate the urethral orifice on the ventral surface
of the vagina.
Restraint for urine collection and
collection
http://www.youtube.com/watch?v=HHFlU
0Ry_tY&feature=player_detailpage
 http://www.youtube.com/watch?v=mrmE
QxUh4YA&feature=player_detailpage
 http://www.youtube.com/watch?v=HqRPS
XgjaAE&feature=player_detailpage
 http://www.youtube.com/watch?feature=p
layer_detailpage&v=ht150ZFT0Ss

Cow Urine Collection
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http://www.youtube.com/watch?feature=p
layer_detailpage&v=lJ__wNhbWn0
Bladder Expression
http://www.youtube.com/watch?feature=p
layer_detailpage&v=9_9PtTP3PPY
 http://www.youtube.com/watch?v=yoYWs
6OEfJI&feature=player_detailpage
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Urinary Sediments
Formed elements: epithelia, red cells,
white cells
 Crystals
 Mucus
 Renal casts
 Microorganisms
 Sternheimer-Malbin stain
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Microscopic UA
Correlate with cloudiness and other
findings
 Quality control
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Consistent volume
Centrifugation
Well mixed fresh specimen
Microscopy (wet mount, use low light)
Sternheimer-Malbin stain
Epithelia
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Squamous epithelia
◦ Large flat cell with central oval nucleus
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Transitional (bladder) epithelia
◦ Spindle shaped with large oval nucleus
◦ Maybe in sheet
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Renal tubular epithelia
◦ Small cell with large oval nucleus
◦ Most clinically significant
Squamous Epithelia
Transitional Epithelia
Renal Tubular Epithelia
Leukocytes
Pus, or pyuria
 May indicate urinary tract infection UTI if
more than 10/HPF
 Glitter cells in dilute alkaline urine
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Pyuria
Bacteriuria
Erythrocytes
Hematuria may indicate renal damage
 Menstrual contamination
 May be crenated or ghost cells
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Hematuria
Renal Casts
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Cylindruria
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Renal stasis
Acidic pH
Proteinuria
Concentrated urine
Tamm-Horsfall mucoprotein matrix
Renal Casts
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Hyaline
◦ Least significant
◦ Not refractile
Coarse and fine granular
 Cellular
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◦ Classified by cells in the cast
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Waxy
◦ End stage renal disease
Hyaline Cast
Fine Granular Casts
Coarse Granular Cast
RBC Casts
WBC Casts
Epithelial Casts
Fatty Cast
Broad Cast
Waxy Casts
Mucus
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Usually of no clinical significance
Common Crystals in Acid pH
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Amorphous urate
◦ Orange powder
◦ May clear with warming or saline
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Uric acid
◦ Brown lemon shaped or star shaped
◦ Birefringent with polarized light
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Calcium oxalate
◦ Envelope
Amorphous Urate
Uric Acid
Calcium Oxalate
Common Crystals in Alkaline pH
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Amorphous phosphate
◦ White powder
◦ May clear with saline
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Triple phosphate
◦ Coffin lid
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Ammonium biurate
◦ Thorn apple
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Calcium carbonate
◦ Effervesce with SSA
Amorphous Phosphate
Triple Phosphate
Ammonium Biurate
Calcium Carbonate
QUESTIONS?