Specimen management

Specimen Collection

* collected during acute phase of illness

* technique should minimise contamination

* transported to lab within 2 hours

* containers should be leak-proof, in sealed biohazard bags, with separate section for paperwork

Specimen preservation

Urine

Boric acid to maintain colony counts

Faeces (Ova Cysts Parasites)

Polyvinyl alcohol or Buffered formalin preserve OCPs

Holding/Transport Media

Stuart's or Amie's maintain viability of microorganisms

Charcoal may be added to absorb fatty acids and stabilise pH

Blood, Bone Marrow, Synovial Fluid

Anticoagulants: SPS, best at low conc;

Heparin, may inhibit Gram-pos bacteria and yeasts;

Citrate/citric acid/dextrose (ACD) and EDTA not suitable for microbial specimens

Specimen Storage

Refrigeration (4C)

Ambient Temp (22C)

Body temp (37C)

Frozen -20C or -70C)

Urine, stool, viral, sputa, swabs, foreign devices

Serum for serological study (for up to 1 week)

Tissues / specimens for long term storage

REJECT

Mislabelled

Improperly transported

Insufficient quantity

Leaking containers

Specimen is in a fixative (exc. OCPs

Anaerobic culture requested on sample known to have anaerobic normal flora

Dried

If processing would provide little medical value

Macroscopic examination

Type of specimen

If blood or mucous is present

Viscosity

Colour / Turbidity

Clots

Microscopic examination

Quality

Early indication of infection

Identify potential pathogens

Compared to direct smear

Definitive ID req for:

Blood cultures

Life-treatening infections

Antimicrobial testing