3.5 General requirements for specimen processing
The following general considerations for specimen processing are relevant for all sample types processed for bacterial culture, identification and AST:
- Poor-quality specimens, or specimens that are poorly transported – for example, in a leaking container – should be rejected. A local SOP should be developed for this.
- Specimens must be labelled appropriately, with three identifying data points (such as name, date of birth and hospital number) and should match the request form. The time and date of collection should also be indicated.
- The request form should include relevant clinical information, including the suspected diagnosis, which may help the laboratory decide on sample processing, and whether any additional precautions should be taken.
- Normal flora should not be reported.
- Strict protocols are required for submission of specimens from non-sterile sites, such as pus from open wounds.
- Laboratory procedures must require appropriate volumes of specimens to maximise recovery of the pathogens. Clinicians should be aware of the optimal volumes for different samples.
- Laboratories must follow strict laboratory SOPs.
- Specimens must be collected prior to antimicrobial administration, unless taking the sample would delay administration of emergency antimicrobials. For example, if the initial attempt at lumbar puncture for suspected meningitis was unsuccessful and the patient was very unwell, it would not be appropriate to delay antimicrobials any further.
- AST should be reported for all clinically relevant isolates.
- Microbiology reports must be clinically relevant.
- The laboratory and medical staff should develop SOPs and technical policies relating to the submission of specimens.
Laboratory personnel receive a urine specimen collected 24 hours prior in a container that has leaked, leaving only a drop of urine. On the label, the patient’s name is unclear, but it is assumed that they have received initial empirical treatment. What recommendations should laboratory staff follow regarding management of this specimen?
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- A specimen of poor quality or that is poorly transported, such as in a leaking container, should be rejected.
- The specimen must be labelled appropriately and completely; if not, it must be rejected.
- Strict instructions for submission of urine specimens must be in place and followed.
- The specimen must be collected prior to antimicrobial administration, if possible.
- Urine specimens must be refrigerated if transport to the laboratory is not possible within two hours.
- The microbiology laboratory should send a report about the rejected specimen to the clinician and ask for a repeat sample if clinically indicated. For critical specimens (such as CSF samples), the clinician should be contacted immediately.
The laboratory should provide an easily accessible list of tests available to all users, including guidelines, turnaround times and other information on their relevance. Ideally this should be available in an electronic format so that it can be easily updated.
3.4 Guidance for collecting and transporting specific samples
