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System involved

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									                                                                                                  Virological assessment of patients:-
 Visit                                                                  a brief guide for General Practitioners

                                                                                                                                                                          Sample collection
Tests for recent infection (see table on the reverse)                                               Specimen collection
                                                                                                    Please use virus PCR sample solution (VPSS) for sample transport (but not for blood-
    a. Polymerase chain reaction (PCR) for viral nucleic acid (either RNA or DNA) is our            borne viruses). To obtain this, phone lab and leave your name and address and quantity
       front-line assay to detect many viral pathogens. Preferred specimens are from the            required. VPSS has long shelf life at room temperature. It is ideal for genital herpes,
       system where you think the virus is, as early as possible. For example, in                   vesicular rash, eye swabs and respiratory swabs. Use a dry swab, squeeze the swabbed
       suspected respiratory infection please collect respiratory specimens rather than             material into VPSS and discard the swab. Do not leave the swab in VPSS. Use sterile
       blood for antibodies and in patients with a vesicular rash, collect vesicle fluid or         saline for throat gargle and NOT VPSS.
       swab rather than blood for antibodies.
    b. In non-specific illnesses such as malaise, tiredness, myalgia etc., unless there are         Urgent specimens
       localising symptoms / signs, it is not worth sending sera.                                   a) Pregnant, in recent contact with a case of chickenpox: if there is convincing evidence
    c. Sera remain useful, especially for HIV, hepatitis viruses, erythrovirus B19,                    of chickenpox in the past, no testing is necessary. Otherwise, please supply details of
       measles, rubella, EBV and Mycoplasma pneumoniae. Please do not send serum                       date of contact and type of contact (face-to-face / same room for 15 minutes / own
       for respiratory or gastrointestinal viruses. Antibody tests are insensitive and IgM             child).
       may not appear early on in illness.                                                          b) For all other urgent testing please phone the laboratory so that we can identify your
    d. Please provide brief patient clinical details with duration of illness , which allows us        patient’s specimen. Include your contact number on the request form.
       to choose appropriate tests.
    e. Suspected viral haemorrhagic fever or SARS or other exotic viruses in returning              Dispatching
       traveller: contact virus laboratory and local Infectious Diseases unit for discussion.        Routine specimens – route through local microbiology laboratories or through
       Public health may have to be involved at a very early stage.                                     alternate local arrangements or through collection van in the case of North Glasgow
                                                                                                        University Hospitals NHS Trust.
Tests for immunity                                                                                   Urgent specimens during working hours – discuss with lab first, then send by
                                                                                                        collection van or Taxi.
    a) Post-vaccine testing for immunity is NOT recommended for measles, mumps, VZV                  Urgent specimens out-of-hours - discuss with on-call virologist.
       and HAV as the assays used are not sensitive enough for vaccine induced IgG.
    b) Tell us about the dates and doses of HBV or rubella vaccines administered.                   What NOT to do ……
    c) We can test for immunity (from natural exposure) to - CMV, EBV, erythrovirus B19,            Please avoid the term ‘viral titres’ because it is confusing and obsolete.
       HAV, HBV, VZV and T. gondii.                                                                 Please avoid sending ANY unsigned request forms, especially for HIV testing. Please do
                                                                                                    not send request forms without patient’s date of birth and your telephone number. Please
                                                                                                    do not send specimens from suspected myocarditis and chronic fatigue syndrome, contact
                                                                                                    lab first for discussion.

Common/SVCservice/targeted guide/24/02/10
       Table showing diseases and specimens to be collected for virological diagnosis;  = preferred sample,  = second-choice sample
                                                                                          Lesion specimens                       Respiratory specimens (one of these is enough)           Excretory specimens      Blood
    System                                      Common pathogens in                                    Swabs in VPSS                                                         Others
                     Clinical features                                                                                                                                                                            Acute +
   involved                                         community
                                                                                                                           Throat and Mouth /          Throat                 NPA                               convalescent
                                                                             Vesicle       Eye     Conjunctival Genital                                          Sputum                    Urine    Faeces
                                                                                                                             nasal     oral            gargle               (children)
Systemic         Pyrexia                     Influenza (in the season)                                                                                                                                          
                 Lymphadenopathy             EBV (<40 years), CMV,
                                             Toxoplasma gondii                                                                                                                                                      
Gastrointestinal Hepatitis                   HAV, HBV, HCV                                                                                                                                                          
                 Gastroenteritis             Rotavirus (infants)
                                             Norovirus                                                                                                                                                
Genito-urinary Suspected HIV                                                                                                                                                                                        
(GUM)          Vaginal discharge,            C. trachomatis
               urethritis, PID                                                                                                                                                              
               Vesicles / ulcers             HSV                                                                   
Haematological Persistent anaemia            Erythrovirus B19                                                                                                                                                       
               Thrombocytopaenia             EBV                                                                                                                                                                    
               Atypical lymphocytes          EBV, CMV                                                                                                                                                               
Ophthalmic       Conjunctivitis, keratitis   Adenovirus, C. trachomatis,
                                             HSV, VZV                                        or 
Nervous          Aseptic Meningitis          Enterovirus
system           Encephalitis                HSV, VZV                                                                                             Phone lab to discuss before sampling                            
                 Febrile convulsions         Any virus                                                                                                                                                            
                 Peripheral neuropathy       Viral aetiology is rare in UK             Call the lab to discuss possibilities based on patient travel history
Respiratory      Common cold, croup,         Rhinovirus, parainfluenza
                 bronchiolitis, ‘flu’,       virus, EBV, adenovirus,                                                             or          or          or  or                                                
                 pharyngitis                 influenza virus
                 Pneumonia                   M pneumoniae, C.
                                             pneumoniae, influenza                                                              or          or          or  or                                                 
Skin and         Mouth ulcers                HSV, enterovirus                                                                              
mucosa           Maculopapular rash          Erythrovirus B19                                                                                                                                                       
                 Vesicular rash              VZV, HSV, enterovirus                                                                                                                                                
                Nodule                       Molluscum contagiosum                     Consider sending nodule biopsy
                Warts                        HPV                                       Contact lab
Musculoskeletal Myalgia                      Erythrovirus B19, M.
                Arthralgia                   pneumoniae and influenza                                                                                                                                                

Common/SVCservice/targeted guide/24/02/10

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