SAMPLE COLLECTION
, Sample Collection
Pre analytical Stage
Proper filling of request form
Collection of specimens,
Handling ,
Transportation and
Processing of Specimens for Microbiological
Investigations
,
,
, General concepts and rules for specimen
collection
Collect specimens –
• In the acute phase of infection
• Prior to antibiotic therapy
• From the correct anatomic sites
• Using proper techniques
• Appropriate quantity and number
• Aseptic measures
• Appropriate container
• Proper labeling
• Early transport
• Use of appropriate transport media
• Criteria for rejection of samples
, Types of samples
1. Blood/Serum
2. Pus
3. Secretions
4. Body fluids - CSF, Peritoneal, Pleural fluid, Joint
fluid
5. Tissue
6. Specialized devices- catheter tips
7. Special fluids - IV fluids, dialysis fluid, water, etc.
, Origin of samples
Collection of samples from
different sites
A. Deep closed area - Blood,
CSF, Pleural or peritoneal
fluid etc
B. Deep communicating area -
Urine, sputum
C. Superficial area - Skin,
Throat, stool,etc
, Collection of samples from closed deep abscess
– Clean the overlying skin with 70% ethanol
• Allow to dry
• Using a sterile syringe – aspirate the contents
• Transfer to a transport media - Stuart
transport
• For anaerobic culture - inoculate into an
anaerobic transport media,
• OR Expel residual air from syringe and stick
the needle into a rubber stopper.
, Collection of samples from superficial wound
• Clean the surface with 70% ethanol
• Allow to dry
• Aspirate or swab from undermined area/pockets
• Transfer to a transport media - Stuart transport
• Sample is not usually cultured for anaerobic bacteria
• IF IT IS BURN OR DECUBITUS ULCERS - TAKE MULTIPLE SAMPLES
• Collection of Urine:
• For Microscopy only- collect into a clean wide mouth container
• For culture - collect into a sterile wide mouth container
• Amount - 10-15 ml
• Storage and transport - Should be stored at 4-80C if processing is
delayed by > 2 hrs
, Transportation of Urine
If urine is transported from periphery without
refrigeration then collect in sterile container with
1% boric acid.
• Boric acid preserves the cellular morphology
and bacterial viability without multiplication