Infection Sciences Tel: Fax: Our Ref: CH/PMF/CI. Date: 12/04/2016. To: Infection Sciences Users.

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1 Infection Sciences Tel: Fax: Our Ref: CH/PMF/CI Date: 12/04/2016 To: Infection Sciences Users Dear Colleague Communication to users I wish to inform you of updated Microbiology, Virology and Immunology specimen acceptance criteria and of changes relating to urine reporting and test repertoire. These changes have come about following a comprehensive review of our processes as the laboratory undergoes transition from Clinical Pathology Accreditation to the newer ISO standards. IS sets out internationally recognised standards of quality and competence for medical laboratories. Specimen containers and storage times The correct container for the sample is very important as it affects the sample volume and any needed additives such as preservatives or transport media to maintain viability of microorganisms. It is necessary to ensure that the specimens arrive and are processed within a time frame appropriate to the nature of the requested examinations and that protects the specimens from deterioration. Appendix 1 details specified containers and acceptable alternatives, and recommended maximum storage times between sample collection and examination commencement. Failure to use the correct container may result in the specimen being rejected. Specimens received outside of the stated maximum storage time will be considered as deviating samples and a comment will be applied to the report stating that validity of the result may be compromised. Supplies of containers can be obtained from stores CIC (ext , direct dial (01228) ) or the laboratory office WCH (ext hospital users only- community and GP users contact WCH stores utilising order form). Forms for ICE order communications may also be ordered on these numbers.

2 Urine microscopy Routine urine samples are screened using automated microscopy. In the absence of significant numbers of white cells (less than 25/µml) or bacteria samples are reported directly with "no evidence of infection" and culture is not performed. Exceptions to this rule are urine samples from paediatrics, pregnant and immunosuppressed patients when culture is performed regardless of microscopy result. When white cells are detected at significant levels the cell count is now given as a numerical value rather than a range. Test repertoire review To maintain or improve quality and reliability of results, the laboratory have reviewed and rationalised the test repertoire. Appendix 2 lists the tests which are no longer available and gives recommendations for alternative diagnostic methods where available. Additionally, tests not available in-house may be sent by the laboratory to the relevant reference centre. Referred samples will be reported as such. Laboratory staff or the Consultants in Microbiology or Immunology will be happy to discuss individual requirements and encourage consultation about the most appropriate testing strategy. Please refer to the updated pathology users handbook for further information. Yours sincerely Dr C Hamson Head of Department Consultant Microbiologist

3 Appendix 1 Specimen containers and storage time Microbiology s Specimen Type Superficial wound swab/ MRSA screen Deep seated wound swab Genital swabs Gonococcus (GC) Screen Per-nasal swab for Bordetella species (Whooping cough). Tissue Pus Bile Fluids from sterile sites Drain Fluids Cerebrospinal Fluid (CSF) CAPD Fluid Specified transport medium with charcoal transport medium with charcoal transport medium with charcoal Liquid transport swab (orange cap) Per-nasal swab (blue cap with thin wire shaft) Dialysate Bag Acceptable Alternative transport medium with charcoal (cell count only) Maximum storage time between sample collection and examination commencement 48 hrs 48 hrs* *3 hrs for culture of anaerobic organisms 48 hrs* *24 hrs for Neisseria gonorrhoeae investigations *2 hrs for Trichomonas investigation 24 hrs 24 hrs 48hrs* *3hrs for culture of anaerobic organisms 2 hrs 2 hrs Sputum/BAL 60 ml sample 24 hrs

4 Specimen Type For Cystic Fibrosis patients (only if patient cannot expectorate) Faeces Urine Samples for investigation of dermatophytes Blood Cultures Specified container (white or silver cap) with integral spoon (blue cap) 10 ml urine collection tube with boric acid. Supplied with collection cup. (red cap) 5 ml urine collection tube with boric acid (Paediatric) (red cap) Dermapak Aerobic (blue cap) and anaerobic (purple cap) blood culture bottles. Acceptable Alternative Cough swab Amies transport with charcoal with boric acid. (red cap) Paediatric (yellow cap) blood culture bottles Maximum storage time between sample collection and examination commencement 48 hrs 24 hrs* *2 hrs for Clostridium difficile investigations 96 hrs Stored dry at room temperature 96 hrs Despatch to the laboratory immediately - do not refrigerate

5 Virology/Immunology s The following containers are available for Virology/immunology samples: Blood containers o Plain bottles for serum o EDTA o Heparin. Roche COBAS transport medium for Chlamydia trachomatis and Neisseria gonorrhoea PCR. Two types: one for swabs and one for urine samples Virology swabs - Remel Microtest medium plus swab- store at room temperature Universal containers (30mL white top) SAMPLE CONTAINER Viral swab/transport media Chlamydia swabs Universal container (30mLs) Clotted blood EDTA Fluoride/Oxalate TYPE Remel Microtest. Red lid-4 ml pink fluid Roche COBAS buffer 4.3mL Yellow cap-clear fluid White cap Vacutainer red cap Vacutainer lilac cap Paediatric small pink cap Yellow cap

6 Appendix 2 Test repertoire review The following tests have been withdrawn and are no longer available: TEST COMMENT Anti-saccharo Bartonella serology Enterovirus IgM Paul Bunnell test Legionella Serology Direct immunofluorescence for respiratory viruses (adenovirus, influenza etc.) Direct immunofluorescence for RSV Complement fixation tests (CTFs) (viral and atypical bacterial antibody titres) Diagnosis is by PCR on tissue biopsy sample Diagnosis is by PCR Replaced by E.B virus serology tests Replaced by urinary antigen detection test Diagnosis is by PCR Replaced by rapid antigen detection test These tests are no longer offered as a routine screen. Alternative serological or molecular testing strategies are available depending on the clinical presentation. Please contact the laboratory to discuss a specific case if required. Note a review of clinical details on previous CFT requests indicated that for a significant proportion the patient was under investigation for tiredness or chronic fatigue. Please refer to NICE guidance for investigation of Chronic fatigue syndrome/myalgic Encephalomyelitis (NICE CG 53). Serological testing should not be carried out unless the history is indicative of an infection. Depending on the history, tests for the following infections may be appropriate: chronic bacterial infections, such as borreliosis chronic viral infections, such as HIV or hep B/C acute viral infections, such as infectious mononucleosis latent infections, such as toxoplasmosis, Epstein Barr virus or cytomegalovirus.