Instructions for Completion of the
Request Form and Sample Labelling
- Confirm the identity of the patient.
- The patient's name must be on all specimen containers
- A request form must accompany all specimens to the
The form should show clearly the patient's details including:
- Three unique patient identifiers: First name, Surname, Date of
birth, Hospital/Clinic number, Medical Record Number (MRN)
- Type of specimen and anatomical site, where appropriate (eg
- Date and Time of sample collection
- Tests required
- All relevant clinical data including: antibiotic treatment,
foreign travel, pregnancy, underlying conditions the patient may
have (eg diabetes, cystic fibrosis) and other conditions that may
affect the patient's immune system
- Risk status if applicable (legal requirement) eg high risk
- If either the request form is not completed correctly or the
sample is not adequately labelled a request may be rejected as
processing the samples may result in misidentification of the
patient constituting a clinical risk.
- Whenever possible samples should be collected before the
administration of antibiotics.
- Instrument, containers, and other equipment coming in direct
contact specimens must be sterile.
- The material to be cultured must not come in contact with
chemicals or germicides eg disinfectants for genital cleansing
prior to the collection of urine cultures.
Procedure for "High-Risk"
Specimens (Hazard Group 3)
- High risk specimens are those that could, potentially, contain
Hazard group 3 pathogens. For a list of organism categories refer
to the Advisory Committee on Dangerous Pathogens (ACDP) Approved
List of Biological Agents (http://www.hse.gov.uk/pubns/misc208.pdf)
- High-risk specimens must be labelled with the appropriate
biohazard sticker and placed in a sealed outer risk container
during transport to the laboratory.
- The accompanying request form must also carry the biohazard
label, as well as sufficient clinical data to enable laboratory
staff to know what special precautions are necessary in the
Specimen problems and Sample
Specimens arriving to the laboratory that are correctly labelled
and sealed will be dealt with promptly and without delay.
Unlabelled specimens will not normally be processed. Please ensure
that all lids are secured before transporting the specimen as
leaking samples cannot be processed and will need to be
Requesting additional examinations on
Specimens already sent
Where possible the laboratory will perform additional
investigations on specimens that have already been received.
Additional tests should be requested as soon as possible after the
specimen is sent.
Microbiology specimens do not store well. Besides, some of the
procedures used in the initial investigation may use the entire
sample or render it unsuitable for further investigations.
The types of specimen required by the laboratory are listed in the
table below. It is important that we receive the correct specimen
type in the correct container. Specimens for bacteriological
investigation should be collected into a sterile laboratory
specified container. This ensures that contaminating organisms do
not interfere with the interpretation of the test and that the
container is free of substances that may affect the culture
Key Factors That May Affect Test Performance/
- Delay in transport: This may affect the
viability of pathogens and allow overgrowth of normal flora or
contaminating organisms. The morphological appearance of cells may
also be affected.
- Excessive temperature: In general,
bacteriology samples should be kept under cool conditions. As the
temperature increases bacterial activity may also increase leading
to misleadingly high counts of pathogens or overgrowth of normal or
contaminating flora. Also, high temperatures may kill the target
organism. Some organisms do not tolerate cooling well and so there
is no substitute for rapid transport. The use of boric acid
containers should be considered whenever the transport of urines to
the laboratory is delayed.
- Inappropriate specimens, site or transport
medium: If the specimen is taken from the wrong site or it
is the wrong type of specimen (eg swab instead of pus) or it is put
in the wrong transport medium (eg viral instead of bacterial
transport medium, dry swabs) then the optimal recovery of the
target organism(s) will not be possible.
- Insufficient Clinical Data: It is essential
that the appropriate clinical information is supplied. This will
include the specific anatomical site and the sample type, history
of any foreign travel, any contact with animals and occupation if
relevant. Failure to provide relevant information may result in the
most appropriate investigation not being performed.
- Specimens should be collected into sterile, leak-proof
- The specimen should be sealed in a specimen bag and the
attached request form completed with full patient information,
clinical history and specimen details as appropriate.
- The specimen should be transported to the laboratory as soon as
possible after collection to allow the most accurate interpretation