The Department of Microbiology is located on level 5 in Derriford Hospital, Plymouth. Microbiology provides laboratory services and the control of infection team. We are a large department employing over 50 members of staff comprising medical, scientific, ancillary and clerical grades. The department processes in excess of 500,000 specimens each year. We provide a comprehensive diagnostic microbiology, serology and molecular biology service.
Due to sample collection variables with Microbiological specimens we rely heavily on how the specimen is collected. If you receive a result that is different than what you expect clinically, consider sending a repeat specimen. Uncertainty of measurement figures are available for some tests upon request.
Factors that could affect Microbiology results
To ensure the accuracy of results please adhere to the following points of good practice;
- Take swabs carefully and follow any specific sampling guidance on the pathology test list app to ensure that the infection is sampled and not normal skin flora or other contaminating organisms
- An actual pus or tissue sample in a sterile container is often better than a swab (unless looking for Herpes Simplex Virus, a swab is preferred in this case)
- Specimens should be collected before antibiotics regimens initiated
- Specimen site/anatomical location must be included on the request form or electronic request as bacteria present on the skin would be interpreted differently from a swab of a sterile site
- Relevant clinical information should be provided for correct interpretation i.e. “dog bite wound” is better than just “wound”
- Specimens should be sent to the laboratory as soon as possible, delayed specimens may lead to misleading results, please refrigerate specimens if a delay is likely (NB Not blood cultures)
- Samples for cell counts such as CSF or sterile fluid counts must be received into the laboratory within 2 hours
Note also you may see specimen specific comments added to reports outlining any factors that may have affected results (for example if the sample was delayed in receipt to the laboratory) please use this information during clinical interpretation
Factors that could affect serology/molecular results
- Most tests are stable for 24 hours at room temperature, any longer than this the specimen can be refrigerated for a maximum of 48 hours before sending to the laboratory (except Quantiferon which must be incubated as soon as possible)
- Stool specimens-ensure specimen is not contaminated with toilet paper or water
- Serology specimens must have clinical information highlighting if
- The patient is receiving treatment/diagnosis with mouse monoclonal antibodies, Vitamin H (biotin) or immunoglobulin
- The patient is routinely exposed to animals or animal serum
- The patient is on heparin
- The patient has immunosuppression, systemic lupus erythematosus or multiple myeloma
- the patient has had a blood transfusion
Data Protection Policy:
Microbiology Department regards the lawful and correct treatment of patients’ personal information as vital to successful operations and to maintaining the confidence of users of the service. Our policy is to treat personal information lawfully and correctly and therefore we fully endorse and adhere to the principles of data protection defined in the General Data Protection Regulation
As part of University Hospitals Plymouth NHS Trust we also work to its governance and data protection policies which incorporate the General Data Protection Regulation
Patient consent is required for the use of tissues removed at surgical procedures for research (with certain exceptions), transplantation or obtaining medical information relevant to another person e.g. genetic information.
Consent is not required for the use of tissue from living patients for the following purposes; clinical audit, quality control, public health monitoring, education or training in relation to human health, although it is good practice to inform patients that their tissues may be used for these purposes via patient information literature, and should any patient specify that they do not want their samples to be kept or used for such purposes, these should be respected. These latter uses of tissue are essential to ensure the high quality of service, which all patients have the right to expect. Wherever possible, samples of tissue used in this way should be anonymised or pseudonymised.
As a department, we aim to provide you with the best possible service at all times. If you have cause to send feedback regarding the service you have received, whether a complaint or compliment, please contact one of the managers below. We will do all we can to help.
- Pathology Quality Team
Phone 01752 430097
The Quality Policy of the Department of Microbiology.
In order to ensure that the needs and requirements of users are met, the Department of Microbiology will:
Operate a quality management system to integrate the organisation, procedures, processes and resources.
Offer a range of clinical microbiological, serological and molecular services as befits the needs of the users.
At the laboratory’s Annual Management Review, set measurable quality objectives that will be reviewed regularly by management throughout the year to assess their progress, effectiveness and implementation.
Ensure that staff are familiar with the contents of the Quality Manual and all procedures relevant to their work
Ensure that all personnel are familiar with this quality policy to ensure user satisfaction.
Commit to the health, safety and welfare of all its staff. Visitors to the department will be treated with respect and due consideration will be given to their safety while on site.
Uphold professional values and commit to good professional practice and conduct.
The Department will comply with the ISO15189:2012 standard for medical laboratories and submit to assessment by the United Kingdom Accreditation Service (UKAS) to ensure:
Staff recruitment and retention, training, competency and development at all levels to provide a full and effective service to its users
The proper procurement and maintenance of such equipment and other resources as are needed for the provision of the service
The use of examination procedures that will ensure results of the highest achievable quality and value to users
Reporting results of examinations in ways which are timely, confidential, accurate and clinically useful.
Communicating with users and assessing their satisfaction with the laboratory’s service, in addition to internal audit and external quality assessment, with a view to continual quality improvement.
|Useful Telephone Numbers|
|Microbiology Results and General Enquiries||437745||37745|
|On call Consultant or named Consultant (If urgent bleep via switchboard)||437745||37745|
|Dr Jim Greig, Director of Infection and Prevention Control, Consultant Medical Microbiologist|
|Dr Robert Tilley, Joint Head of Department, Consultant Medical Microbiologist|
|Dr Rosie Fok, Consultant Medical Microbiologist & Lead for Antimicrobial Stewardship|
|Dr Lewis Jones, Joint Head of Department, Consultant Medical Microbiologist|
|Mr Allan Speirs, Laboratory Manager||433270||33270|
|Mr Neil Cooper, Lead Biomedical Scientist of Bacteriology||433603||33603|
|Mr Mark Wallis, Lead Biomedical Scientist of Virology||437750||37750|
Microbiology Opening Hours
|Monday – Friday 09.00 – 17.30||Normal Service|
|Monday – Friday 17.30 – 08.00||On call service|
|Saturday/Sunday/ Bank holidays 08.00 – 16.30||Limited service|
|Saturday/Sunday/ Bank holidays 16.30 –09.00||On call service|
Meet our Team
ALLAN SPEIRS, Microbiology Laboratory Manager
DR. L JONES, Head of Department Consultant Microbiologist
DR. R TILLEY, Head of Department Consultant Microbiologist
MARK WALLIS, Lead Biomedical Scientist - Virology
NEIL COOPER, Lead Biomedical scientist - Bacteriology
Since October 2016 the Microbiology laboratory has been accredited to the international standard ISO15189:2012, ‘Medical laboratories – Requirements for quality and competence’. Its schedule of accredited tests can be found at: www.ukas.com
Labelling of request forms and specimen containers
Where possible, samples should be requested electronically using the Hospital iCM system, or GP ICE system. This has the benefit of reduction in transcription errors, increases data legibility, saves paper and saves laboratory time in booking samples.
If paperless electronic ordering is not available then samples will be accepted if adherence to the following information is made.
The appropriate microbiological investigations that are performed on a specimen are selected on the basis of data included on the request form, and results are also interpreted in the light of this information. Consequently, in addition to the usual requirements for patient name, hospital and NHS number and date of birth, it is important to include adequate clinical information on each form. Please complete a fresh request form for each sample, as forms may be required to be sent to separate areas of the laboratory. Details to be included and the reason for their inclusion are given below:
- Patient’s address: In some cases, this is important epidemiological information (e.g. identification of clusters of infections in the community, contact tracing, etc.).
- Date of birth: Some microbiological tests performed on the specimen may be selected purely on grounds of age (e.g. examination for rotavirus in stool specimens of children)
- Nature of specimen: This must be specified. For example, straw-coloured fluid in a container could be urine, aspirate from a joint, peritoneal fluid or CSF .
- Relevant history/clinical information: The history may indicate which microbiological tests are relevant. Interpretation and appropriate further examination of the culture is often dependent on the given clinical history .
- Site, nature and duration of infection: Different parts of the body tend to have their own flora which may be commensal (harmless) at one site and pathogenic at another (e.g. Staphylococcus aureus may be carried asymptomatically in the nose but be the cause of an infected surgical wound). Please also indicate date of onset of infection and details of recent surgical operations
- Antibiotic therapy: Failure to include details of antibiotic therapy may result in a misleading report. The antibiotic may inhibit growth of the causative organism or select resistant strains which colonise the site. This information also ensures that appropriate susceptibility tests are performed on significant isolates.
- Date and Time of Collection: Different organisms survive for varying periods and some grow well at room temperature. If normal flora are present, their survival and subsequent multiplication may make results hard to interpret.
Rejection of specimens
Sample and request form information must be compatible and complete. Unlabelled specimens, specimens where information on the sample container and the request form do not match, or specimens received without an accompanying request form (unless it is an iCM or ICE sample) will not be examined. However, for unrepeatable specimens (e.g. CSFs, blood cultures), an attempt will be made to contact the sender in order to clarify the situation, and the samples may then be processed in the usual way. An entry shall be made on the report pertaining to the discrepancy.
Samples require a minimum number of 3 points of identification
The points of identification are:-
- NHS number
- Full Name
- Date of birth
- Hospital Number
If request does not contain the correct amount of details as described above the following report will be issued.
“There was insufficient information with this request to uniquely identify the patient; therefore the sample has not been examined.
“Please arrange a fully labelled repeat sample, if still clinically indicated”
Please ensure that GP/consultant name and name/bleep/telephone number of requester are stated.
These enable laboratory staff to communicate quickly with medical staff if there are any queries. The name of the consultant or GP also helps in monitoring requesting patterns and workload. The bleep number is particularly helpful for hospital inpatients.
These should be handed separately to transport staff, who will ensure that they are delivered appropriately to laboratory staff. This facility is for requests requiring results for the immediate management of the patient. Urgent requests are regularly audited.
Specimens for urgent analysis, which are delivered to the laboratory by Taxi or other transport, should be hand delivered to the appropriate laboratory and should not be left at the main reception. The IATA Dangerous Goods (DG) Regulations state that members of the public should be protected from the risks of potentially infectious substances. A code of practice for staff involved in specimen transport is available on request from the Pathology Directorate office.
If an urgent (telephoned) result is required this should be noted on the request form and the laboratory informed by telephone. The ‘red spot’ system does not apply to Microbiology samples. For urgent specimens outside normal working hours see On-Call Repertoire below.
Some specialist tests not performed by this department will be sent to approved reference laboratories. When this occurs, the initial report will state that a reference laboratory report is to follow. When the final report is issued, the reference laboratory will be identified. More information about the reference facilities used will be published on this website in due course.
Specimens associated with forensic legal investigations must be accompanied by a “Chain of Evidence” form. This form can be obtained from the Microbiology Department (Tel Ext: 43375).
On arrival at the laboratory explain the nature of the specimen and request the attendance of a senior member of staff. Out of hours contact the oncall Biomedical Scientist.
The best results are obtained when an appropriate, well taken specimen, in the proper container, is delivered to the laboratory promptly and relevant clinical information is provided on the request form.
General guidelines on specimen collection are:
• Do not send specimens in non-sterile containers
• Specimens should be obtained before antimicrobial agents have been administered
• An adequate quantity of material should be obtained for complete examination.
• Always send pus rather than a swab of the pus.
• The specimen taken should be representative of the disease process. For example material swabbed from the opening of a sinus tract is more likely to yield commensal skin flora than material obtained by curettage or biopsy of the base of the tract.
Care must be taken to avoid contamination of the specimen by micro-organisms normally found on the skin and mucus membranes. Sterile equipment and aseptic technique must be used for collecting specimens particularly for those from normally sterile sites.
For safe disposal of materials used in the collection of specimens (gloves/sharps etc) please refer to your local guidelines.
Material must be transported promptly to the laboratory. Fastidious organisms may not survive prolonged storage or may be overgrown by less fastidious organisms before culturing (ideally samples should reach the laboratory no later than 24 hrs after taking the specimen).
Please contact the laboratory if there is any doubt about the most appropriate specimen to take or concerning the availability of a test.
Patient collected samples
Self-collected samples are currently used by the chlamydia screening office for chlamydia testing. Full instructions are issued to patients with the sample packs. There is a similar arrangement for SHiP patients to self-collect blood samples for HIV and syphilis testing
Self sent samples
No self sent samples or samples from family members will be accepted for testing.
Specimen risks to laboratory staff
- All biological specimens are a potential hazard to hospital staff and should be safely contained when transported to the laboratory.
- The specimen container must describe the nature of the specimen, correct patient details, and the patient’s location.
- Each specimen must be placed in a clean specimen bag and correctly sealed.
- If a specimen is known or suspected to pose an increased risk of infection, it is the responsibility of the individual taking the sample to ensure that this information is made known to laboratory staff. This will allow laboratory staff to take additional precautions where appropriate.
- The request form MUST give sufficient clinical information to specify the suspected, or known infection
NOTE: The Health and Safety Executive has recently highlighted the lack of clinical details as resulting in samples being handled in laboratories at the wrong biological containment level, thereby placing laboratory staff at increased risk (HSE Bulletin No. HID 5-2011).
Examples of specimens which pose an increased risk of infection:
- Any specimen from a patient suspected of having TB, typhoid, anthrax or brucellosis
- Stool specimens from patients with haemorrhagic colitis (bloody diarrhoea), haemolytic uraemic syndrome, or suspected of having VTEC/STEC including E. coli 0157 infection
- Stool specimens from patients with suspected dysentery (Shigella)
- Any specimen from a patient suspected of having a spongiform encephalopathy (e.g. CJD)
- Any specimen from a patient suspected of having viral haemorrhagic fever. These must be discussed with the on-call Consultant Microbiologist prior to submission to the laboratory.
Under no circumstances should a specimen be sent in a leaking or contaminated container. The laboratory may dispose of hazardous specimens without testing them if the sample presents a risk to staff due to inadequate information or packaging.
Additional tests can be requested on samples already submitted dependent upon the age and nature of the sample as detailed below;
- Serology blood samples – If sufficient sample remains, further tests can be requested up to 12 months after submission, excluding PCR testing which will require a fresh sample.
- Sputa – Additional testing for TB can be requested up to 2 days after initial sample processing
- Additional testing (non-TB) can be requested within 24 hours of receipt of sample.
- Urine samples – Additional testing for Chlamydia can be requested up to 48 hours after sample has been processed
- Urine Samples – Additional tests (Not Chlamydia) can be requested within 24 hours of sample receipt
- Swabs – additional tests can be requested up to 48 hours after sampling, however certain fastidious organisms e.g. Neisseria gonorrhoeae may not be viable.
- Stool Samples – additional tests can be requested up to 48 hours after receipt of sample.
Reviewed June 2023
This page will be updated December 2023