Skip to main content
Oxford University Hospitals NHS Foundation Trust

This site is best viewed with a modern browser. You appear to be using an old version of Internet Explorer.

Microscopy and culture of deep seated samples

This test covers the bacteriological investigation of tissue, fluid and pus swabs from abscesses, deep seated sites and normally sterile fluids, to diagnose infection.

Specimen requirements

Tissue and fluids are the preferred specimen type and should be taken before commencing antimicrobial therapy.

Specimens should be sent in a sterile container. Swabs in appropriate transport media are also processed. Specimens should be transported and examined as soon as possible. However, if processing is delayed then refrigeration is recommended.

More details on the specimen requirements for certain sample types can be found in our manual:

Laboratory turnaround time

The turnaround time for these samples is two to 14 days.

Laboratory method

Non-selective and selective culture media is used to isolate organisms from the primary specimen.

In addition, the inoculation of an enrichment broth is used to isolate aerobic or anaerobic organisms which may be present in low numbers.

Differential cell counts are performed on CAPD and ascitic fluids (or when requested) to assist in the diagnosis of infection.

Gram stains are performed on most specimens and examination for crystals is performed when requested. N.B. Gram stains are no longer performed on swabs.

Where to find results of these tests

  • All results are returned electronically where possible (EPR, SunquestICE).
  • Some results may be phoned to clinicians and GPs.
  • Results are never given directly to patients by the laboratory staff.

Further information and contact details

For further information please email:

Confidential patient information should only be sent from accounts.