2. Urine
Examination

3. Defination of urine
• Urine (from Latin Urina, ae, f.) is a
typically sterile liquid by-product of the
body secreted by the kidneys through a
process
called urination and excreted through
the urethra.

4. Possible pathogens
• BACTERIA
Gram positive Gram negative
Staphylococcus saprophyticus Escherichia coli
Hemolytic streptococci Pseudomonas aeruginosa
Klebsiella strains
Salmonella typhi
Salmonella paratyphi
Neisseria gonorrhoeae

5. Parasites
(a) wuchereria bancrofti
(b) schistosoma hematobium
(c) trichomonas viginalis
(d) enterobius vermicularis
• Bladder and urinary tract are normally sterile.
• Urethra and perineum has wide variety of
gram positive and negative organisms.
(a) (b)
(c) (d)

6. Collection of urine specimen
• The first voided morning urine (most
concentrated) - qualitative
• Random urine (routine)
• 24hrs sample- quantitative
• Mid-stream clean catch (most suitable for
urine culture)
• Post prandial sample.
• Need to be examined within 1 hour.

7. Collection and transport
• Give patient sterile,dry,wide necked leak proof container and
request 10-20 ml specimen.(clean catch specimen)
• Cleanse the area around urethral opening with clean water,dry the
area and collect urine with labia held apart.
• Wash hands before collecting specimen
(middle of urine flow)
• Label container with date & name.
• Number of patient & time of collection.
• As soon as possible, deliver specimen
with request form to laboratory.

8. Collection and transport
• Give patient a sterile,dry,leak proof container with
instructions how to collect a clean catch MSU.(mid
stream urine)
• Add measured amount of boric acid powder (0.1g/10ml
of urine) to preserve a specimen.
• Label container and send urine
with request form to reach
microbiology laboratory within
48 hours.

9. Laboratory examination of urine
• Appearance of specimen
Appearance Possible cause
Cloudy (urine has unpleasent smell and
contains WBCs)
Bacterial urinary infection
Red &cloudy (due to red cells) Urinary schistosomiasis
Bacterial infection
Brown &cloudy (due to hemoglobin) Black water fever
Intravascular hemolysis
Yellow brown or green brown
(due to bilirubin)
Acute viral hepatitis
Obstructive jaundice
Yellow orange
(due to urobillin)
Haemolysis
Hepatocellular jaundice
Milky white
(due to chyle)
Bancroftian filariasis

10. Colour and turbidity in urine
specimens

11. Microscopical examination of Urine
• Round,10-15 um in diameter.
• Report
• Few upto 10 wbcs/HPF
• Moderate:11-40/HPF
• Many:more than 40
WBCs/HPF.
• Definite outline and no
granules.
• Reported as
few,moderate,many in number
/HPF (high power field)

12. Microscopical examination of Urine
(a) A hyaline cast with a 'fluffy'
appearance due to the fibrillary
substructure of Tamm–Horsfall
glycoprotein .
(b) A hyaline–granular cast.
(c) A finely granular cast.
(d) A waxy cast

13. Microscopical examination of Urine
• Oval shape and some yeast
• Show single budding
• Yeast are reported as
few,moderate or many /
HPF(higher power field)
(a) Uric acid crystals
(b)calcium oxalate crystals.
(c) calcium phosphate
(d) Triple phosphate
crystals.

14. Biochemical test for urine
• Biochemical tests which
are helpful in
investigating UTI (Urinary
tract infection )
include
• Dipstick method is mostly
used in chemistry labs.

15. CULTURE THE SPECIMEN:
Culture is required when the urine contains
bacteria(as indicated by Gram
smear),cells,casts,proteins and nitrite.
• Normal specimens may be contain small amount
of organisms(less than 10,000/ml of urine)
• In untreated acute infections the number of bacteria
will be more than 100,000/ml.

16. METHODS OF ESTIMATING BACTERIAL
NUMBERS
1. Using quarter plates of culture media
2. Inexpensive
3. Simple to perform
4. Provides individual colonies
(
)

17. CYSTINE LACTOSE ELECTROLYTE
DEFICIENT
(CLED)
• Allows the growth of both gram
negative and gram positive
pathogens
• Electrolyte deficient to prevent
swarming of Proteus species
• Bromothymol blue indicator
• Lactose fermenting colonies
appears yellow

18. • Mix the urine by rotating the container
• Using a sterile wire loop,inoculate a loopful
of urine on plate of CLED ager
• Incubate at 35-37°C overnight

19. CULTURE IDENTIFICATION
:
(CLED agar culture)
• look for colonies that could be:
• Escherichia coli
• Proteus species
• Pseudomonas aeruginosa
• Klebsiella strains
• Staphylococcus aureus
• Staphylococcus saprophyticus
• Enterococcus faecalis

20. E.coli:
Klebsiella species:
Proteus species:
Pseudomonas aeruginosa:
Enterococcus faecalis:
Staphylococcus aureus:
Coagulase negative staphylococci:
CONTAMINATION SHOWS MIXED GROWTH

21. REPORTING BACTERIAL NUMBERS
• Estimate the number of bacteria,i.e colony
forming units(CFU) per ml of urine
• Report the bacterial count as:
Less than 10,000 organisms/ml
10,000-100,000/ml
More than 100,000/ml

22. INTERPRETATION OF BACTERIAL COUNTS
• Interpret culture count in relation to clinical
conditions.
=> urinary
infections
=> infection or contamination
(repeat specimen)
=> contamination
• UTIs with low counts in urinary obstruction.

23. ANTIMICROBIAL SUSCEPTIBILITY
TESTING
• On urines with significant bacteriuria, particularly
in recurring UTI (Urinary tract infection).

24. TESTING URINE FOR HCG
(PREGNANCY TESTING)
• First morning specimen.
• Based on detection of rapidly rising levels of
hCG in urine or serum.
• Investigation of suspected ectopic pregnancy,
threatened abortion or trophoblastic tumor.
• IC (immuno chromatographic) card and strip
tests are able to detect 50mlU/ml of hCG.