Microbiology

Notes

Sample requirements

30 mL sterile Universal container

Samples of pus are preferred to swabs.

Ideally, a minimum volume of 1mL of pus is required.

30ml universal container

Standard charcoal transport swab

Well soak swab in pus.

Place swab into transport medium

Black top charcoal swab

Required information

  • Relevant clinical details
  • Site of lesion
  • Nature of lesion e.g. abscess, carbuncle
  • IVDU
  • Diabetes
  • History of immune compromise/immunosuppression treatment
  • Gangrene
  • Suspected actinomycosis
  • Recent, current and intended antibiotics

Storage/transport

Pus samples - transport as soon as possible. If there is any delay pus samples should be refrigerated.

Swab samples - store and transport at room temperature. Samples should be transported to the laboratory with minimal delay.

Turnaround time

Microscopy on day of receipt (pus samples only).

A preliminary report is issued after 2 - 4 days. All cultures undergo an extended 5 day incubation for anaerobes.

Final negative: 5 - 6 days

Final positive: up to 7 days

Certain organisms such as Actinomyces spp and Mycobacterium spp require longer incubation