2. Topics to be covered . . .
• Indications of urine examination
• Composition of urine
• Collection and Preservation of urine
• Physical examination
3. URINE ANALYSIS
One of the most commonly performed laboratory tests.
Simple, non invasive, economical.
Progression /Regression of various lesions can be monitored with
minimal distress to patient.
Systemic d/s, Endocrine/Metabolic detected through recognition of
abnormal amount of disease-specific metabolites excreted in
urine.
4. Indications Of Urine Examination
• Suspected renal diseases like glomerulonephritis, nephrotic
syndrome, pyelonephritis, and renal failure
• Urinary tract infection
• Metabolic disorders like Diabetes Mellitus
• Differential diagnosis of Jaundice
• Plasma cell dyscrasias
• Pregnancy
• Specialized tests like catecholamines/metanephrines for diagnosis of
Pheochromocytoma, screening for illegal drugs
6. COLLECTION AND PRESERVATION
a)The first voided specimen in the morning
b)The random specimen
c)Postprandial specimen
1.Time Of
Collection
SINGLE
SPECIMEN
24 hrs
SPECIMEN
7. 2. Method of collection
a) Midstream specimen
b) Clean-Catch specimen
c) Catheter specimen
d) Plastic bag specimen
e) Suprapubic aspiration
f) Three-glass specimen
8. Changes Causes
Increased ph Urea Ammonia
Crystals Precipitation of phosphates and
calcium
Decreased glucose Glycolysis and utilization by
bacteria
Loss of ketone body Volatile
Negative bilirubin test Bilirubin biliverdin
Negative urobilinogen Urobilinogen urobilin
Increased odor & decreased clarity Bacterial proliferation
9. PRESERVATION:
Preservation Concentration Uses
Refrigeration 2-8 °C Prevent bacterial
proliferation & no
interference with chemical
test
Hcl 30ml/24 hr urine VMA,Catecholamine,creatini
ne,5-hydroxyindole acetic
acid
Toluene 30ml/24hr urine Physical barrier for
bacteria, oxalate, cystine
Boric acid 10g/24 hr urine Urea, glucose, cortisol,
aldosterone,
metanephrines, uria, uric
acid
Thymol 10% in
Isopropanol
10ml/24 hr urine Cellular elements
Formalin 10% 10ml/L Urine sediment
Nitric acid 15ml/24hr urine Metal analysis
11. Volume
• Normal range - 600-2000 ml/ 24 hr.
• Abnormalities in volume
• Polyuria : >2000 ml urine/24 hours.
• e.g. Diabetes mellitus, Diabetes insipidus, chronic renal failure,
diuretic therapy
• Oliguria : <400 ml/24 hours
• e.g. shock, acute nephritis, congestive cardiac failure, dehydration
• Anuria : complete suppression of urine formation (<100 mL/24 hours)
• e.g. renal failure, acute tubular necrosis, complete urinary tract
obstruction
12. Color Condition
Pale yellow/ amber Normal
Colorless Diluted urine - DM, DI, Overhydration
Yellow Concentrated urine
Yellow green or green Biliverdin
Deep yellow with yellow foam Billirubin
Orange/ orange brown Urobillinogen, Porphobillinogen
Red Hematuria & Hemoglobinuria
Red/ orange fluorescence with UV light Porphyria
Brown Hemoglobinuria
Dark brown or black Alkaptonuria & melanoma
Milky white Chylouria
Blue green Pseudomonas infection, chorophyll
Color
13. Odor
Freshly voided urine has a typical aromatic odor due to volatile organic
acids.
• Foul : Urinary tract infection
• Fruity or sweety : Ketoacidosis, starvation
• Mousy or musty : Phenylketonuria
• Fishy : Urinary tract infection with Proteus, Tyrosinaemia.
• Ammoniacal : Urinary tract infection with Escherichia coli, old
standing urine.
• Rancid : Tyrosinemia
• Sweaty feet : Isovaleric acid
• Maple syrup or burnt sugar : Maple syrup urine disease
15. Specific Gravity
• Defined as density of solution as compared to density of
distilled water.
• Normal SG -1.003 TO 1.030
• Causes of increase in SG (Hypersthenuria) - DM, Nephrotic
syndrome, Fever, Dehydration.
• Causes of decrease in SG (Hyposthenuria) - DI, CRF,
Compulsive water drinking.
• Isosthenuria - Constant SG at 1.010
17. 1.Reagent Strip Method
• Measures the concentration of ions in urine, which correlates
with SG.
• Depending on the ionic strength of urine, a polyelectrolyte will
ionize in proportion.
• This causes a change in color of pH indicator (bromothymol
blue)
18. 2. Refractometer Method
• It measures the refractive index of the total soluble solids.
• Higher the concentration of total dissolved solids, higher the
refractive index.
• Extent of refraction of a beam of light passed through urine is a
measure of solute concentration, and thus of SG.
• Advantage - simple and requires only
1-2 drops of urine.
• Result is read from a scale or from
digital display.
19. 3. Urinometer Method
• Principle – Buoyancy.
• Accuracy of urinometer needs to be checked
with distilled water at the temperature of
calibrations
• Correction for temperature: 0.001/every 3°C
• Correction for dilution
• Correction for abnormal solute concentration
Protein – 0.003
Sugar – 0.004
20. pH :-
Measuring acidity or alkalinity
On standing alkaline.
Litmus paper test Reagent strip test
pH meter pH indicator paper
21. Acidic urine Alkaline urine
Ketosis (DM, Fever, Starvation)
UTI by E.coli
High protein diet
Old urine sample
UTI by proteus or
pseudomonas
Sever vomitting, CRF
22. Automation in Urinalysis
Definition :- Automation refers to machines with
intelligence and adaptability which reduces workload
and non stop supervision.
Principle of Automated Urine Analysis
1 2 3
Automated urine strip
reading by reflectance
photometry
Fluorescent flow
cytometry
Automated
microscopy
Types of Automated Urine Analysis
Semi Automated
Fully automated
24. ADVANTAGES :-
Enhances work flow saving laboure and time.
Standardizes some aspects of manual urine analysis.
Reduces subjective errors.
Large number of samples in short time.
Performed on UNCENTRIFUGED URINE.
25. Common errors :-
Differences in lighting conditions.
Difference in individual skill, failure to keep specified
time.
Loss of reagent reactivity due to improper storage.
Discoloration of strips by bilirubin, blood or other
constituents.
26. REFERENCES
• Henry’s Clinical diagnosis and management by laboratory
methods,(23rd ed) Pg.no:442-446
• Kawthalkar Shirish M, Essentials of Clinical Pathology,Jaypee
Brothers Medical Publishers (P)Ltd,(3rd Ed)Pg.no:16-
20,India,2023
• Susan king strasinger, Urinalysis and body fluids, 6th Ed,
Pg.no:27-35,59-66