C5: Specimen Collection and Handling

aspirates and tissues

• must be collected using sterile techniques

• samples must be protected from drying

swabs

• from the upper respiratory system

• last resort for wound specimens

aspirates

Which is more preferable: swabs or aspirates?

unopened

Which is more preferable: aspirates from unopened or opened wounds?

urine

• perianal region must be washed

• mid-stream

sputum/lower respiratory spns

• expectorate deeply

• first morning specimen is best

• aspiration may be necessary

stool

• kits/containers should be provided

• contamination should be avoided

• use of sterile containers may or may not be necessary

boric acid

preservative used for urine

phosphate buffered saline

preservative used for stool

sodium polyanethol sulfonate

most common anticoagulant used

heparin

anticoagulant used for viral cultures

citrate and EDTA

two anticoagulants that must not be used for bacteriology

keeps the organisms viable and inhibits replication

What is the purpose of holding and transport media?

• Carey-Blair

• Modified Stuart transport media

• Amies

most commonly used holding/transport media

4 °C

refrigeration temperature

37 °C

incubator temperature

25 °C

room temperature

-20 or -70 °C

freezing temperature

unprotected specimens

must be processed without delay

refrigeration

for urine, viral blood spns, catheters, swabs

incubator

for CSF, bacterial blood spn, cultures on agar plates

room temperature

spns for the isolation of fungus

freezing

temp for if processing will be delayed for more than 4 days