The document provides information about urine analysis, including its importance, the examination process, and various tests. It discusses: - Urine analysis involves macroscopic, chemical, and microscopic examination to diagnose conditions. - Tests include assessment of physical characteristics like volume, color, and specific gravity as well as chemical tests for proteins, sugars, ketones, blood, and bile. - Proper collection and preservation methods are outlined to transport urine samples to the laboratory for analysis within 2 hours to avoid deterioration. - Common chemical tests described are Benedict's test for sugars, Rothera's test for ketones, and heat and acetic acid test for proteins.

1. URINE ANALYSIS

2. • Examination of urine is important for
diagnosis of many conditions
• Routine examination of urine is divided into 3
parts

3. Routine urinalysis
(1) Macroscopic analysis - assessment – physical
characteristics
(2) Chemical analysis
(3) Microscopic analysis - formed elements.
 Important & cost effective lab test
 screening test, used most frequently -
 helps in assessment of kidney dysfunctions
 monitoring response to treatment
 to note progression of a disease

4. Urine collection
• Collected in a clean container
• Labelled with Name, age, sex, identity number, date
and time of collection
• 3 ways
Spontaneous voiding ---- simplest and best method
Urethral catheterisation
Suprapubic bladder puncture.
A clean catch urine sample should be obtained.
Midstream collection, in females reduces
contamination by vaginal elements

5. Transport to laboratory & analysis
• Best - immediate, analysis within 2 hours
• Beyond 2 hours:
 physical and chemical composition changes
 formed elements deteriorate.
• If urine cannot be analysed immediately, appropriate
preservation will slow deterioration of urine
• refrigeration(2-8 degree)
• There is no good substitute for immediate examination.

6. METHODS OF PRESERVATION
• Should be examined fresh or within one hour of
voiding
1. Refrigeration at 4 degree C
2. Toluene
3. Formalin
4. Thymol
5. Hydrochloric acid
6. Sulphuric acid
7. Boric acid

7. • universal preservative
• 1 ml per 50 ml of urine
• Forms a surface layer and preserves the
chemical constituents of urine
Toluene

8. • Formalin
6 - 8 drops of 40% formalin per 100 ml of
urine
Preserves RBCs and pus cells
Disadvantage: False positive test for sugar
• Thymol – 1% of solution used
• Disadvantage – False positive test for protein

9. PHYSICAL EXAMINATION
1. Volume
2. Colour
3. Odour
4. Reaction/pH
5. Specific gravity

10. VOLUME
• NORMAL: 500 – 2500 ml in 24 hours
• Average – 1200 ml
• Polyuria: more than 2500 ml in 24 hours
Physiological- Excess water intake, Winter
Pathological - Diabetes Insipidus, Diabetes
Mellitus
• Nocturia:
more than 500 ml during night
RENAL FAILURE

12. VOLUME
• Oliguria: less than 500 ml in 24 hours
 Less Water Intake
 Dehydration, Renal Ischaemia
• Anuria: less than 150 ml in 24 hours
 Renal Stone
 Tumours
 Renal Ischaemia
 Obstruction in urinary tract

13. COLOUR
• Normally is clear, pale to straw coloured due
to pigment UROCHROME
1. Colourless: DM, DI, Excess intake of water
2. Deep amber colour: Muscular exercise
High grade fever

14. COLOUR….
3. Orange colour
• Increased Urobilinogen
• Concentrated Urine
4. Smoky
• Small amount of blood
• Vitamin B12
• Aniline Dye

15. COLOUR ….
5. Red – Haematuria, Haemoglobinuria
6. Brown – Bile
7. Milky – Pus , Fat
8. Green – Putrefied Sample, Phenol poisoning

17. Odour
• Normally - FAINT AROMATIC
1. Pungent – AMMONIA PRODUCED BY
BACTERIAL CONTAMINATION
2. Putrid – UTI
3. Fruity – KETOACIDOSIS
4. Mousy - PHENYLKETONURIA

19. pH
• Reflects ability of kidney to maintain H+ion
concentration in extracellular fluid and plasma
• Measured by
1. pH indicator paper
2. Electronic pH meter
• Normal urine is slightly acidic 4.6 – 7
• Average - 6

20. ACIDIC URINE
• Conditions
1. High protein intake- meat
2. Acidic fruits
3. Respiratory acidosis, Metabolic acidosis
4. Urinary tract infection E coli

21. ALKALINE URINE
• Conditions
1. Citric Fruits
2. Vegetables
3. Respiratory Alkalosis, Metabolic Alkalosis
4. UTI by Proteus, Pseudomonas

23. SPECIFIC GRAVITY
• Ratio of weight of 1 ml volume of urine to that of
weight of 1 ml of distilled water
• Depends on concentration of particles/solutes in
the urine
• Used to measure the concentrating and diluting
power of kidney

24. SPECIFIC GRAVITY …
• Measured by
1. URINOMETER
2. REFRACTOMETER
3. REAGENT STRIP METHOD

30. REAGENT STRIP METHOD
• Depending on the product being used, Urine
Reagent Strips provide tests for Glucose,
Bilirubin, Ketone (Acetoacetic acid), Specific
Gravity, Blood, pH, Protein, Urobilinogen,
Nitrite, Leukocytes, and Ascorbic Acid
in Urine.
• The entire reagent strip is disposable.

35. TEST PRINCIPLE
• Glucose: This test is based on a double sequential
enzyme reaction. One enzyme, glucose oxidase,
catalyzes the formation of gluconic acid and
hydrogen peroxide from the oxidation of glucose.
• A second enzyme, peroxidase, catalyzes the
reaction of hydrogen peroxide with potassium
iodide chromogen to oxidize the chromogen to
colors ranging from blue-green to greenish-brown
through brown and dark brown.

36. Contd..
• Bilirubin: This test is based on the coupling of
bilirubin with a diazotized dichloroaniline in a
strongly acid medium.
• The colors range from light tan to reddish-
brown.
• Ketone: This test is based on the reaction of
acetoacetic acid with sodium nitroprusside in
a strongly basic medium.
• The colors range from beige or buff-pink color
for a “Negative” reading to pink and pink-
purple for a “Positive” reading.

37. Contd..
• Specific Gravity: This test is based on the apparent
pKa change of certain pretreated polyelectrolytes in
relation to the ionic concentration.
• In the presence of an indicator, the colors range
from dark blue or blue-green in urine of low ionic
concentration to green and yellow-green in urine of
higher ionic concentration.

38. Contd..
• Blood: This test is based on the pseudoperoxidase
action of hemoglobin and erythrocytes which
catalyzes the reaction of 3,3’, 5, 5’-tetramethyl-
benzidine and buffered organic peroxide.
• The resulting colors range from orange to yellow-
green and dark green.
• Very high blood concentration may cause the color
development to continue to dark blue

39. Contd..
• pH: This test is based on the well known double pH
indicator method, where bromothymol blue and
methyl red give distinguishable colors over the pH
range of 5-9.
• The colors range from red-orange to yellow and
yellow-green to blue-green.
• Urobilinogen: This test is based on a modified
Ehrlich reaction in which p-
diethylaminobenzaldehyde reacts with urobilinogen
in a strongly acid medium.
• Colors range from light pink to bright magenta

40. Contd..
• Protein: This test is based on the protein error-
of-indicator principle.
• At a constant pH, the development of any
green color is due to the presence of protein.
Colors range from yellow for a “Negative”
reaction to yellow-green and green to blue-
green for a “Positive” reaction.

41. Contd..
• Nitrite: This test depends on the conversion of
nitrate to nitrite by the action of Gram-
negative bacteria in the urine.
• The nitrite reacts with p-arsanilic acid to from a
diazonium compound in an acid medium.
• The diazonium compound in turn couples with
1,2,3,4- tetrahydrobenzo(h) quinolin to
produce a pink color.

42. Contd…
• Leukocytes: This test is based on the action of
esterase present in leukocytes, which catalyzes
the hydrolysis of an indoxyl ester derivative.
• The indoxyl ester liberated reacts with a
diazonium salt to produce a beige-pink to
purple color.

43. Contd…
• Ascorbic Acid: This test is based on the action
of a complex chelating agent with a polyvalent
metal ion in its higher state and an indicator
dye that can react with the metal ion in its
lower state to produce a color change from
blue-green to yellow.

44. TEST PROCEDURE
• Remove from the bottle only enough strips for
immediate use and replace cap tightly.
• Completely immerse reagent areas of the strip in
fresh, well- mixed urine.
• Remove the strip immediately to avoid dissolving
out the reagent areas.
• While removing, touch the side of the strip
against the rim of the urine container to remove
excess urine.

45. Contd…
• Blot the lengthwise edge of the strip on an
absorbent paper towel to further remove excess
urine and avoid running over (contamination
from adjacent reagent pads.)
• Compare each reagent area to its corresponding
color blocks on the color chart and read at the
times specified. Proper read time is critical for
optimal results.
• Obtain results by direct color chart comparison

48. All reagent areas except Leukocytes may be read between 1-
2 minutes for screening positive urine from negative urine.
Changes in color after 2 minutes are of no diagnostic value

51. URINE EXAMINATION - II
CHEMICAL TESTS FOR URINE

52. Chemical Tests
• Proteins - Heat and Acetic acid Test
• Sugars - Benedict’s Test
• Ketones – Rothera’s Test
• Blood – Benzidine Test
• Bile Pigments – Fouchet’s Test
• Bile Salts – Hay’s sulphur Test

53. PROTEINS

54. Heat and Acetic acid test
Principle:
• When a solution containing protein is boiled,
denaturation takes place resulting in formation of
insoluble coagulum which is precipitated at pH of
their isoelectric point

55. Heat and Acetic acid test for proteins
Fill 2/3 rd of test
tube with urine
sample and heat
top column
(lower column
acts as control) to
boiling.
Add 3 drops of
1% acetic acid.
Heat.
Degree of
cloudiness
persistent in
upper column of
tube.
Albumin and
Globulin

56. Sulfosalicylic Acid
Principle:
• Addition of acid to protein neutralizes the
+vely charged proteins by –vely charged acids
resulting in precipitation of proteins

57. Sulfosalicylic Acid
2 ml of
urine+
equal amt.
of Exton’s
Reagent
(5%
Sulfosalicy
lic acid in
a solution
of sodium
sulfate)
Grading for cloudiness----
-ve-no cloudiness
Trace-cloudiness is just
perceptible against a black
background
1+-- cloudiness is distinct but not
granular
2+-- cloudiness is distinct and
granular
3+-- cloudiness is heavy with
distinct clumping
4+-- cloudiness is dense with large
clumps that may solidify
Albumin
and
Globulin

59. CARBOHYDRATES

60. Benedict’s Semi quantitative Test for
Sugars
5 ml of
Benedict’s + 0.5
ml (8 drops)of
urine boil for 2
min & cool.
% of sugars
Green: 0.5%
Green ppt: 0.5-1%
Green to yellow:1-
1.5%
Yellow to red: 1.5-2%
Brick red: >2%
Reducing
sugars

63. Sugars detected by Benedict’s test
 Glucose
 Galactose
 Lactose
 Fructose
 Maltose
 Pentose
• False +
 Ascorbic acid, Creatinine, Uric acid
 Salicylates
 X-ray contrast