 Specimen must be collected in a clean dry, disposable
a wide mouth container, flat bottom to prevent
overturning and properly applied screw top lids.
 Made of clear material to allow for determination
of color and clarity.
 Capacity of the container is 50 mL, which allows 12 mL of specimen
needed for microscopic analysis, additional specimen for repeat analysis.
 Sterile containers are also suggested if more than 2 hours
elapse between specimen collection and analysis.
 Container must be properly labeled with patient name,
date, and time of collection.
 The labels should be applied to the container and not to
the lid.
Label here
Note that :
 The specimen must be delivered to the lab & must be
delivered within1 hr
 If you expect the specimen to stay for a long time, it should be
Refrigerated or have an appropriate chemical preservative
added. eg. (Toluene, thymol, formalin or boric acid).

Transformation of urea to ammonia which increase pH.









Decrease glucose due to glycolysis and bacterial utilization.
Decrease ketones because of volatilization.
Decrease bilirubin from exposure to light.
Decrease urobilinogen as it oxidized to urobilin.
Increase bacterial number.
Increase turbidity caused by bacteria & amorphous.
Increase nitrite due to bacterial reduction of nitrate.
Disintegration of RBCs casts, particularly in diluted alkaline urine.
Changes in color due to oxidation or reduction of metabolic.
1. Random specimen (at any time)
 Useful for routine screening but may

give false results due to dietary
intake or physical activity just prior to the collection of the specimen
It’s not useful for quantitative analysis.
2. First morning specimen




Valuable as it’s concentrated to reveal abnormalities and formed
elements
It’s free of dietary influences and changes due to physical activities
Prevents false negative pregnancy test
Useful in evaluation of orthostatic proteinuria.
3. 24 hr’s collection
Used for quantitative determination and for evaluation the kidney
function.
Post. Prandial sample : It taken at specified time
4.
after specific meal to know the normal excretion.
5.


6.
7.
Clear catch sample (midstream urine ):
Best for bacteriological work
it’s collected by cleaning the genitalia then the
patient takes the midstream urine which is suppose
to be the most sterile one.
Catheterized urine: Collected form pediatric or
adult that can’t give urine.
Supra - pubic samples: For bacteriological samples
and taken from pediatric mainly.
A routine urine analysis (R+M) Routine + Microscopic
includes the examination of physical & chemical
characteristics of microscopic studies of some cellular &
non-cellular elements.
1. Appearance: (color and clarity)
Normal urine color has a wide range of variation ranging
from pale yellow, straw, light yellow, yellow, dark yellow
amber due to urochrome pigment (it’s an end product of
endogen metabolism), trace of urobilin and uroerythrin.
The color is affected By :

Concentration of urine, pH, Metabolic activity, Diet
intake and Some Drugs
1. Colorless or pale yellow
2. Dark yellow, Amber, orange
 High fluid intake
 Low fluid intake.
 Reduction in perspiration.
 Using of diuretic.
 Nervousness
 Alcohol ingestion
 Diabetes Mellitus.
 Excessive sweating
 Carrots or vitamin (A)
 Dehydration (burns, fever).
 Pyridium and nitrofurantoin
(drugs).
 Diabetes Insipidus (Low level of antidiuretic hormone).
3. Brownish yellow
 Bilirubin
 Urobilin
on shaking yellow foam will appear.
on shaking the foam has no color.
4. Yellow – green
 Bilirubin
oxd. Biliverdin (greenish).
 Which give a yellow foam & (- ve) test for bilirubin
5. Blue – Green
 Pseudomonas Infection
5. Pink – Red
Due to the presence of fresh blood
or Hb, fresh blood will give smoky
color while Hb gives clear reddish
urine.
Both may be due to
 Trauma
 Calculi
 Urinary tract infection
 Menstrual contamination.
6. Dark brown
 Met hemoglobin if bloody
sample long standed, Hb
will be oxidized.
 Melanin
7. Black Urine
 Alkaptonurea, a disease of
tyrosine metabolism.
Normal urine clear or transparent, any turbidity will indicate.
WBCs (pus).
 RBCs
 Epithelial cells
 Bacteria
 Casts
 Crystals
 Lymph
 Semen.

2. Odor
 Fresh normal urine has a faint aromatic odor due to the presence of
some volatile acids.
 In some pathological conditions, certain metabolites may be produced
to give a specific odor such as:
 Fruity odor is due to
Diabetic urine acetone.
 Ammoniac odor
urine standing long time
 Offensive odor
Bacterial action of pus (UTI).
 Apple odor
Asparagus
 Mousy odor
Phenylalanine (phenyl keto urea
“PKU” ).
3. Volume
Adult urine volume = 600 – 2500 ml /24hr.
Children urine volume = 200 – 400ml /24hr. (4ml / kg / hr).
Volume of urine depends on
1.
2.
3.
4.
Water intake
External temperature.
Mental and physical state.
Intake of fluid and diuretics (Drugs, alcohol – tea).
 Oligouria:
marked decrease in urine flow < 400 ml.
 Polyuria : Marked increase in urine flow > 2500 ml.
 Anuria : complete stoppage of urine flow.
 Nocturia: excessive urination during night.
Causes of polyuria
 Increased fluid in take
(polydipsia
Polyuria).
 Increased salt intake ad protein
diet, which need more water to
excrete.
 Diuretics intake (drugs, drinks)
 Intravenous saline or
glucose.
 Diabetes Mellitus.
 Diabetes Insipidus.
 Renal disease.
 Hypoaldasteronism.
Causes of oligouria
1Water
deprivation
2-
3-
Renal
Dehydration
Ischemia
4Renal
Disease
5Obstruction
by
Prolonged
vomiting
heart failure
Calculi
Diarrhea
Hypotension
Tumor
Transfusion
Reaction
Prostatic
hyper trophy
Excessive
sweating
.
.
Causes of Anuria
No Urination
1. Sever Renal Defect and loss of urine
formation mechanism.
2. Due to the presence of stone or tumor.
3. Post transfusion hemolytic reaction.
4. Specific Gravity (spg)
 Specific
gravity measures urine density, or the ability of the
kidney to concentrate or dilute the urine over that of plasma.
 It is directly proportional to urine osmolality which measures
solute concentration
 It’s a measure of number and size of molecules
 Hence, large molecules such as urea will contribute to reading
more than the small molecules, such as Na+ and K+
 Hence, osmolality may express this function with more effectively
because it’s the number of particles / kg of substance.
Specific
gravity between 1.002 and 1.035 on a random
sample should be considered normal if kidney function
is normal.
Since the spg of the glomerular filtrate in Bowman's
space ranges from 1.007 to 1.010, any measurement
below this range indicates hydration and any
measurement above it indicates relative dehydration.

Low specific gravity
Diabetes Insipidus
Glomerulonephritis
Sever renal damage
(diminish the concentration
ability of the kidney)
Excessive water intake.
High specific gravity
Diabetes mellitus.
Nephrosis
Fever since urine is conc.
Urine preservative
substance
X ray contrast media
1. Urinometer:



Consists of a weighted float a hatched to a scale that
has been calibrated in terms of urine spg. (1.00 –
1.040)
The weighted float displaces a volume of liquid equal
to its weight and has been designed to sink to a level
of 1.000 in distilled water.
The additional mass by the dissolved substances in
urine causes the float to displace a volume of urine
smaller than of D.W. , the level to which the
urinometer sinks represent the specimen spg.
Disadvantages of urinometer:
• The minimum amount of urine to be
measured is about 15 ml.
• If the urine is so turbid it is difficult to
read the result.
2. Refractometer
Determine spg by measuring the refractive index of urine
3. Reagent strip:
Which contain polyelectrolyte, when ions increase in urine,
more acidic groups are released, the change in pH will take
place which change the color of bromothymol blue indicator.
(ions in low spg urine)
C – OO – H+
C – OO – H+
C – OO – H+
Less H+ release because less urine
ions is present so increased pH
(ions in high spg urine)
C – OO – H+
C – OO – H+
C – OO – H+
H+ replaced by urine ions &
released in urine so decreased pH
5. PH

One of the important functions of the kidneys is pH
regulation, the glomerular filtrate of blood plasma is usually
acidified by renal tubules and collecting ducts from a pH of
7.4 to about 6 in the final urine to keep blood pH about 7.4.

Urine pH must vary to compensate for diet and products of
metabolism, this function takes place in the distal convoluted
tubule with the secretion of both H+ & NH3+ and
reabsorption of bicarbonate .

In cases of alkalosis, urinary pH will be alkaline by stop H+
excretion.
Normal urine pH is (4.6 – 8.0) as average (6.0)

1. Determine the existence of metabolic acid base disorder
2. Precipitation of crystals to from stone requires specific pH
for each type. Hence, pH control may inhibit the
formation of these stones by control diet.
 High
protein will give acidic urine.
 High vegetable will give alkaline urine
 In addition to some drugs which control pH.
 Crystals found in alkaline urine: Ca carbonate, Ca phosphate, Mg
phosphate, and amorphous phosphate.
 Crystals found in acidic urine: Ca oxalate, Uric acid, Cystine, Xanthine
and amorphous urate.
3. May indicate the presence of urinary tract infection caused by
urea splitting organisms.
4. Defects in renal tubular secretions and reabsorption of acid &
base.
5. Determination of unsatisfactory specimens.
Even in abnormal conditions, urine pH mustn’t reach 9, if so or more this
will indicate that urine is stand for along time & must be rejected.
Reagent strip which has an indicator (methyl red – bromothymol
blue indicator) or other indicators.
Alkaline urine is found in:
Patient with alkalemia, UTI, diets high with citrus fruits or
vegetables.
Acidic urine is found in:
Patient with acidemia, starvation, dehydration, high diets with
meat products