specimen collection.pdf

COLLECTION AND TRANSPORT
OF SPECIMENS
JITENDRA KUMAR PANDEY
MGM medical college ,mumbai
PG,MEDICAL MICROBIOLOGY 3yr

INTORDUCTION:
Specimen collection and
transportation are critical
considerations , because any results
the laboratory generates is limited by
the quality of the specimen and its
condition on arrival in the laboratory.
Specimens should be obtained to
minimize the possibility of introducing
contaminating microorganisms that
are not involved in the infectious
process.

General guidelines for
specimen collection:
 Depending on the type of infection
e.g. blood
 Aseptic precautions
 Anatomic sites and locations
 Adequate amount/volume
 Tissue or other body fluids should be
preferred over swabs, to get quality
material
 Proper timing
 Clinical laboratory form

An Ideal Request form
 Name xxxx Age Sex
 IP/ OP No xyz Time Date
 Ward xx123 Urgent / Routine
 Nature of specimen
 Investigation needed
Doctor/Staff
Contact No
1234567

 Use of transport media
 Proper handling ,labelling and
transportation
 Use of proper container
 Instruction to the patient
 Before the administration of antibiotics
 Avoid contamination of specimens

SPECIMEN TRANSPORT:
 Within 2 hours of collection
 Containers should be leak-proof
 Separate section for paperwork
 Special preservatives or holding
media
 Biohazard label

Criteria for rejection of
specimens:
Several criteria can be considered by a laboratory on
the basis of which the processing of a specimen
may not be done by the laboratory. Such a decision
must be made in light of the specific requested
investigation. Laboratory investigations of a sample
are a waste of time and resources if following
criteria are not fulfilled :
 Missing or inadequate identification
 Insufficient quantity
 Specimen collected in an inappropriate
container
 Contamination suspected
 Inappropriate transport or storage

Containers and swab for
the collection of
specimens:
Containers:
For faeces:-
• Universal container
• Spoon attached to the
inside of the screw cap

For urine:-
 Universal container for small
quantities
 For larger quantities 250 ml wide
mouthed screw-capped bottles are
convenient
For sputum:-
• Universal container should
not be used
• Squat ,wide-mouthed disposable
containers should be used

For blood:-
• Without anticoagulant for
serological examination
• With EDTA for parasitological
examination
 BLOOD CULTURE BOTTLE:
• This must be at least large
enough to hold 50ml of liquid
medium ,with which it is issued
from laboratory ,plus 5-10ml of
patient’s blood

For serous fluids:-
• Universal container
• Addition of 0.3ml of 20% solution
sodium citrate to the container prior
to autoclaving (with the cap fitted)
is recommended for collection of
fluids that may coagulate on standing
• This avoids difficulty in performing
cell counts or centrifuging procedure
with such fluids

Swabs:-
Swabs suitable for taking Specimens
of exudates from the throat, nostril ,
ear , skin, wounds and other accessible
lesions consist of a sterile pledget of
absorbent material, usually cotton-wool
or synthetic fiber, mounted on a thin wire
of stick
Swabs for special purpose:
 Baby swabs
 Pernasal swabs
 Post-nasal swabs
 Laryngeal swabs
 High vaginal and cervical swabs
 Serum coated cotton wool swab

 Containers of anaerobic
specimens:
 Syringe and needle for aspiration.
 Tube or vial contains semi-solid holding medium an
atmosphere of 5% CO2 ,a reducing agent, tube used for
putting up the swab.
 Readymade swabs in a plastic tube or jacket and
containing either Cary-Blair , Amies transporter pre-
reduced (PRAs) medium id used.
 Plastic pouch or Bio-bag (transparent) containing a CO2
generating system, palladium catalyst and an anaerobic
indicator can also be used.

EYE:
Various specimens collected are:
A. specimens:
1.Conjunctival:-
 Container:
• Aerobic swab moistened with
Stuart’s or Amie’s medium
 Collection:
• Obtained from superior and inferior tarsal conjunctiva
• Specimen of both eyes with separate swabs by rolling swab
over each conjunctiva
• If a viral culture is requested ; a second
specimen is collected
• For Chlamydia culture swabs are taken
with a dry calcium alginate swab

 Transport :
• Within 24hrs/RT
• For viral culture place in viral transport media and deliver
promptly to laboratory or refrigerated
for a short time and then transport on wet ice
• For Chlamydia place in 2-Sp transport medium
2. Corneal scrapings:
 Container:
Bedside inoculation of BA,CA,SDA,7H10,Thio
 Patient preparation:
Clinician should instill local anesthetic before collection
 Collection:
By using heat sterilized platinum spatula or calcium alginate-
tipped swab dipped in sterile trypticase soya broth
 Transport:
Immediately/RT

3. Anterior chamber and vitreous cultures:
Collection:
Aspiration is carried out with a tuberculin
syringe fitted with a
• 25-27 gauge needle for the aqueous
• 20-21 gauge needle for vitreous
aspiration
Transport:
Immediately/RT

EAR:
1. Inner ear:
 Container:
• Sterile , screw-cap tube
or anaerobic transporter
• Clean ear canal with mild
soap solution before puncture
of the ear drum
 Collection:
 Aspirate material behind drum with syringe if ear drum
is intact; use swab to collect material from ruptured
eardrum
 Transport:
• Immediately/RT

2. Outer ear:
Container:
• Aerobic swab
moistened with
Stuart's or Amie’s
medium
Patient preparation:
• Wipe away crust with
sterile saline
Collection:
• Firmly rotate swab in outer canal
Transport:
• Within 24hrs/RT

RESPIRATORY
TRACT(RT):
 Collection of specimen in the case of
RTI poses a number of problems
because , there is enormous
commensal flora that colonizes this
tract.
 Therefore, the specimen collection is
very crucial and specially in case of
viral infections of RT.
 One has to avoid contamination of the
specimens.
 RT is broadly divided into:

A . Upper RT:
Container:
• Swab moistened with Stuart’s or Amie’s medium
Collection:
1.Oral swab:
• Remove the oral secretions or debris
from the surface of lesion with swab and discard
• Using 2nd swab ,vigorously specimen the
lesion avoiding any areas of normal
tissue
2. Nasal swab:
• Use swab moistened with sterile
saline.
• Insert approx. 2cm into nares
• Rotate swab against nasal mucosa

3. Nasopharyngeal:
A. Swabs:
• To collect nasopharyngeal cells, all mucus is
removed
• Small flexible nasopharyngeal swab is inserted
along the nasal septum to the posterior pharynx
• Rotate slowly for 5 sec. against the mucosa
several times
B. Aspirate :
• Is collected with a plastic tube attached to 10 ml
syringe or suction catheter
C. Washings:
• Is obtained with a rubber suction bulb by instilling
and withdrawing 3-7 ml of sterile buffer saline

4.Laryngeal swab:
• Before use the swab is moistened with sterile
D/W
• Patient is made sit and holding the tongue
fully protruded
• with help of a piece of gauge, pass the swab
back through the mouth wire mid-line and
downwards over the epiglottis into larynx
where it should induce reflex coughing that
will expel sputum onto swab
• Withdraw the swab and replace it in its tube
for delivery to the laboratory

5. Throat swab:
• Depress the tongue with
a tongue depressor
• Introduce the swab between
the tonsillar pillars and behind
the uvula without touching the
lateral walls of the buccal cavity
• Swab back and forth across
the posterior pharynx
• Any exudates or membrane should be taken for
specimen
 Transport:
• Within 24hrs/RT

B. Lower RT:
 Container:
• Sterile screw-top container
 Collection:
1.Sputum:
Patient preparation:
Ask patient to brush teeth
and then rinse or gargle with
water before collection
• Collected early in the
morning before eating
• make collection in a
disposable wide mouthed
screw-capped sterile plastic
container of about
100ml capacity

• Instruct to wait until he/she feels material
coughed into his/her throat
• Then work it forward into mouth and spit
it directly into container
• Should be collected before starting
antimicrobial chemotherapy
2.Transtracheal aspiration(TTA):
• Obtained by inserting a small plastic
catheter into the trachea via a needle
previously inserted through the skin and
cricothyroid membrane
• This technique is rarely used any more

3.Bronchioalveolar lavage (BAL):
• 30-50 ml of physiological saliva
is injected through a fiberoptic
bronchoscope .
• the saliva is then aspirated
4.Bronchial brush:
• Is collected via a protected
catheter bronchial brush as part
of a bronchoscopy examination
5.Gastric lavage:
• In the morning before the
patient has taken anything
but after a bout of coughing
and swallowing , aspirate the
fasting stomach contents with
a Ryle’s tube
 Transport:
• Within 24hrs/RT

BODY FLUIDS:
1.Cerebrospinal fluid:
Container:
• Sterile screw-cap tube
• Disinfect skin before aspirating specimen
Collection:
• Lumbar puncture to collect the CSF for
examination to be collected by Physician
trained in procedure with aseptic
precautions to prevent introduction of
Infection.

• The trained physician
will collect only 3-5 ml
into a labeled sterile
container
• The fluid to be
collected at the rate
of 4-5 drops per second.

 The best site for puncture is inter
space between 3 and 4 lumbar
vertebrae
• The Physician should wear sterile
gloves and conduct the procedure with
sterile precautions, The site of
procedure should be disinfected and
sterile occlusive dressing applied to the
puncture site after the procedure.

Transportation to Laboratory:
 The collected specimen
of CSF to be dispatched
promptly to Laboratory ,
delay may cause death
of delicate pathogens,
e.g. Meningococci and disintegrate
leukocytes

Preservation of CSF:
 It is important when
there is delay in
transportation of
specimens to Laboratory
do not keep in
Refrigerator, which tends
to kill H. Influenza
 If delay is anticipated
 leave at Room
Temperature.

2.Pleural/Peritoneal/Pericardial/
Synovial fluid:
Container:
• Sterile screw-cap tube or anaerobic
transporter
• Disinfect skin before aspirating with 2%
iodine tincture
Collection:
• Obtained via percutaneous needle
aspiration or surgery
Transport:
• Immediately/RT

BLOOD:
Container:
• Blood culture media set(aerobic and anaerobic
bottle)
or vacutainer tube with SPS
• Disinfect venipuncture site
with 70% alcohol and
disinfectant such as betadine

Collection:
• Select the vein from which blood is
to be drawn
• Disinfect the venipuncture site
• Allow it to dry
• With precautions to avoid
touching and recontaminating the
venipuncture Site , take the
specimen of blood and put it
immediately through the hole in the cap of bottle
Volume of blood:
• In adult 5-10ml
• In children 1-5ml
Transport:
• Within 2hrs/RT

Gastrointestinal tract(GIT):
1.Stool:
 Container:
• Clean leak-proof container
 Collection:
•Pass stool directly into a sterile, wide-mouth, leak proof
container with a tight fitting lid.
•Pass stool into a clean, dry bedpan, and transfer into a
sterile leak proof container with a tight fitting lid.
 Stool for ova and parasites should be placed in preservative
immediately after collection.
 Transport:
• Within 24hrs/4 °C
• If delay is unavoidable and particularly when the weather is
warm collect the specimens in a container holding 6 ml
buffered glycerol saline transport medium

Cary-Blair All enteric organisms
Stuart All enteric organisms
Amies All enteric organisms
Buffered glycerol
saline
All enteric organisms
except
Vibrios
Campylobacter
Alkaline peptone
water
Vibrios
V-R fluid Vibrios
Transport media for stool specimens

2.Rectal swab:
Container:
• Swab placed in enteric transport
medium
Collection:
 Pass the tip of a sterile swab
approximately 1 inch beyond the anal
sphincter.
 Carefully rotate the swab to sample
the anal crypts and withdraw the
swab. Place the swab in transport
medium.
Transport:

3.Duodenal aspirates:
 Container:
• Sterile, screw-cap tube
• Collect in early AM before patient eats or gets out
of bed.
 Collection:
• Ask the patient to swallow a weighted gelatin
capsule containing a tightly wound length of string,
which is left protruding from the mouth and taped to
the cheek
• After a predetermined period , during which the
capsule reaches the duodenum and dissolves, the
string now covered with duodenal contents is
retracted .
 Transport:

URINARY TRACT INFECTION(UTI):
1.Urine:
 Container:
• Sterile, screw-cap container
Females:
• Clean area with soap and water, then rinse with
water, hold labia apart and begin voiding in
commode; after several ml have passed, collect
midstream
Males:
• Clean glans with soap and water, then rinse with
water, retract foreskin; after several ml have

Collection:
• after several ml have
passed, collect midstream
in a urine container
Transport:
• Within 24hrs/4°C
2.Catheter specimen of urine (CSU):
 Container:
• Sterile, screw-cap container
• Clean urethral area (soap and water) and rinse
(water)

Collection:
• Insert catheter into bladder
• Allow first 15ml to pass
• Then collect remainder
Transport:
• Within 24hrs/4°C
3.Suprapubic bladder aspiration:
• It is used primarily for neonates and small
children but may be safely used in adults
• A full bladder is required for this
• Overlying skin id disinfected
• Bladder is punctured above the symphysis
pubis with a 22-gauge needle on a syringe
• About 10ml of urine is aspirated

HAIR,NAILS, OR SKIN SCRAPINGS
(FOR FUNGUS CULTURE)
Container:
• Clean, screw-top tube
• Nails or skin: wipe with 70% alcohol
Collection:
• Hair: Collect hair with intact shaft
• Nails: Send clippings of affected area
• Skin: Scrape skin at leading edge of lesion
Transport:
• Within 24hrs/RT

ABSCESS:
(also lesions, wounds, pustule, ulcer)
A . Superficial:
 Container:
• Anaerobic swab
moistened with Stuart’s or
Amie’s medium
• Wipe area with sterile saline
or 70% alcohol
 Collection:
• Swab along the leading edge of wound
 Transport:
• Within 24hrs/RT

B . Deep:
 Container:
• Anaerobic transporter
• Wipe area with sterile saline or 70%
alcohol
 Collection:
• Aspirate material from wall or excise
tissue
 Transport:
• Within 24hrs/RT

Genital tract
A . Females:
1.Cervical swab:
 Container:
• Swab moistened with
Stuart’s or Amie’s medium
• Remove mucus before
• collection of specimen
 Collection:
• Swab deeply into
endocervical canal
 Transport:
• Within 24hrs/RT

2 . High vaginal swab:
Container:
• Or JEMBEC transport system
• Remove exudates
Collection:
• Swab secretions and mucous membrane of vagina
Transport:
• Within 24hrs/RT

3 . Urethral swab:
Container:
• Remove exudates from urethral opening
• Collection:
• Collect discharge by massaging
urethra against pubic symphysis
• Or insert flexible swab 2-4cm into
urethra and rotate swab for 2 sec.
• Collect at least 1 hr after patient
has urinated
Transport:
• Within 24hrs/RT

B . Males:
1.Prostrate:
Container:
• Or sterile screw-cap tube
• Clean glans with soap and water
Collection:
• Collect secretion on swab or
• In tube
Transport:
• Within 24hrs/RT for swabs
• Immediately/RT if in tubes

2 . Urethra:
Container:
• Or JEMBEC transport system
Collection:
• Insert flexible swab 2-4cm into urethra and rotate
for 2 sec.
• Or collect discharge on JEMBEC transport system
Transport:
• Within 24hrs/RT for swab
• Within 2hrs for JEMBEC transport system

REFRENCES:
 Specimen Collection In Clinical
Microbiology
Dr. V. L.Malhotra, Dr. Neelam Khandpur
 Bailey And Scott's Diagnostic Microbiology
(12th Edition)
 Koneman’s Colour Atlas Of Diagnostic
Microbiology (6th Edition)
 Textbook Of Microbiology- Ananthanarayan
And Paniker’s(8th Edition)
 Mackie And McCartney Practical
Microbiology(14th Edition)
 Internet

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