Transcript Collecting Processing and Testing Urine Specimens

FACULTY OF ALLIED MEDICAL
SCIENCES
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Clinical chemistry
(MLCC-203)
Dr Eman El-Attar
MLCC 203
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ILOs
1- To understand the different types of urine samples
2- To be able to perform different tests of urine analysis
3- To be able to find abnormal findings in urine
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COMPLETE URINE ANALYSIS
Simple, non-invasive diagnostic test
that provides a window to the
patient’s health (kidney diseases,
DM,UTI…...)
1st thing: you should learn about various types of
urine specimens and how to properly instruct
patients about sample collection .
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SPECIMENS TYPES
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Random
First morning
Midstream
Timed/ 24 hours
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SPECIMENS TYPES
(CONT.)
Random – most common, taken anytime of day
First morning – higher concentration of
substances, taken in morning
Midstream – genitalia is cleaned, urine is tested
for microorganisms & presence of infection
Timed/ 24 hour – used for quantitative analysis
of substances (Instructions??)
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SPECIMEN
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COLLECTION
The specimen must be collected in a clean dry,
disposable container.
The container must be properly labeled with the
patient name, date, and time of collection. The labels
should be applied to the container and not to the lid.
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URINE CONTAINERS
The container should be labeled with:
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the patient name, date, and time of collection

The specimen must be delivered to the laboratory
on time and tested within 1hr,
OR

it should be refrigerated or have an appropriate
chemical preservative added.
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CHANGES OCCUR IN NON
PRESERVED SPECIMEN
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Increase bacterial number.
Increase crystals deposition (amorphous)
Increase turbidity caused by bacteria & amorphous
Decrease glucose due to glycolysis and bacterial utilization.
Decrease ketones because of volatilization.
Decrease bilirubin from exposure to light.
Breakdown of RBCs
Transformation of urea to ammonia which increase pH.
Changes in color due to oxidation or reduction of metabolic
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URINE ANALYSIS
Three types of testing should be
learned:
Physical
Chemical
Microscopic
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PHYSICAL EXAMINATION OF
URINE
Visual examination:
Volume
Color
Aspect
pH (reagent strips, Acidic/Alkaline)
Specific gravity (1015-1025)
 The refractometer or a reagent
strip is used to measure specific
gravity
Refractometer
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Reagent Strips
Color:
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Normal: Amber Yellow
Colorless
Diluted urine
Deep Yellow
Concentrated Urine
Deep Yellow-Green
Bilirubin
Red
Blood (hematuria) / Hb (Hemoglobinuria)
Green
Pseudomonas infection
Brownish-black
Alkaptonuria, Melaninuria
Diet (beet) , drugs (rifampicin)
Aspect:
- Normal aspect: Clear
−
−
Turbidity indicates cells ,crystals , bacteria, yeast.
Microscopic examination will determine which is present.
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CHEMICAL EXAMINATION OF URINE
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Proteins
Glucose
Ketone bodies
Bilirubin
Urobilinogen
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CHEMICAL EXAMINATION OF URINE (CONT.)
Proteins:
Normal urine contains small quantity of proteins
usually less than 20 mg/dL (150 mg/day).

*Qualitative detection:
Heat and acetic acid test.
Urine reagent strips.

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HEAT AND ACETIC ACID
Boil the upper 1/3 of a test tube containing clear urine.
 If turbidity occurs, add few drops of 33% acetic acid.
 If turbidity disappears, it was phosphates.
 If turbidity persists, it was due to proteins
(Trace,+,++,+++,++++).

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URINE REAGENTS STRIPS
Strips impregnated with
indicator that changes its colour
in presence of proteins.
(Nil,Trace,+,++,+++,++++).
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CHEMICAL EXAMINATION OF
URINE (CONT.)
 Glucose – reagent strip
Present in DM, renal glucosuria
 Ketone bodies (acetone) –reagent strip
Present in DKA/ starvation/vomiting
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 Bilirubin:
Seen in obstructive jauindice, liver diseases
Detection:
.
Urine reagent strips
 Iodine test.
- Carefully, layer diluted iodine in absolute ethanol on
urine.
- A green ring is formed at the interphase due to oxidation
of bilirubin to biliverdin.

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 Urobilinogen
Normally, there is a normal
urobilinogen.
Increased in hemolytic anemia
*Detection:

Urine reagent strips.

Erlich test.
trace
of
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MICROSCOPIC EXAMINATION
OF URINE
 Microscopic examination used to view elements not
visible without microscope
 Centrifuge spins urine to cause heavier substances to
settle to the bottom
•Cells
•Bacteria
•Crystals
•Yeast
•Casts
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MICROSCOPIC EXAMINATION
OF URINE (CONT.)
Cells:

RBCs : (0-5/ HPF)
Double
wall,
homogeneous,nonnucleated, 33%AA?

Pus cells: (0-5/ HPF)
Larger,
grainy,colourless
nucleated.
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and
Epithelial cells:
Larger, nucleated
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Crystals: According to urine pH
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In acidic urine:
• Amorphous
urates:
granular
dust
powder(Pink).
• Uric acid: ellipses, triangles or rectangles.
• Ca oxalate: small envelops or octahedral.
In alkaline urine:
• Amorphous phosphates: granular dust powder
(white).
•
•
Triple phosphate: colourless prisms (coffin lid
type).
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Ca oxalate : small envelops or octahedral.
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Casts:
They are moulds of renal tubular endothelial
lining which dislodge, and pass into the urine and
indicate kidney disease.
They form via precipitation of Tamm-Horsfall
mucoprotein which is secreted by renal tubule cells.
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Significance:Kidney damage
Types:
Hyaline casts.
Blood and leucocyte casts.
Epithelial casts.
Granular casts.
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STUDY QUESTIONS
What is iodine test?
 What is the findings in a urine sample of a
diabetic patient ?

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ASSIGNMENT
Describe in full details how to perform blood
sampling on a female patient who wants to do the
following tests:
 CBC
 PT, PTT
 SGOT, SGPt
 Urea, Creatinine

By:
Aysha khedr
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IT’S TIME FOR PRACTICAL
APPLICATION!
END OF
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