Genito-Urinary Samples

General Information

  • STI check for Chlamydia and Gonorrhoea, (and Trichomoniasis in symptomatic females), is done by NAAT testing. (Aptima sample). Annual STI check is recommended for all 18-25 year olds.
  • For the investigation of abnormal vaginal discharge, laboratory testing is often unnecessary. Primary investigation should include clinical observations, and testing the vaginal pH - (PHE July 2013).
    Vaginal Discharge chart
  • LTHT Microbiology do NOT offer diagnostic testing for Bacterial Vaginosis (BV). This diagnosis is made on the basis of clinical observations and vaginal pH. Leeds Sexual Health offer consultancy and a referral service for patients with apparent recurrent or refractory BV. http://leedssexualhealth.com
  • When requesting laboratory GUS culture tests on Order Comms, the result for vaginal pH will determine the relevant investigations to be undertaken.
  • Routine” culture of High Vaginal Swabs (HVS) in asymptomatic patients is of no value.
  • Culture for N gonorrhoeae is only available if there is strong suspicion of gonorrhoea, and treatment is planned. Swabs should be processed within 6 hours. Referral to LSH is recommended in such cases.
  • For detection of group B streptococci (GBS) in pregnancy, a high vaginal swab may be sent. Note that a positive MSSU with GBS during pregnancy warrants peripartum antibiotic prophylaxis irrespective of GBS status on HVS culture – therefore, sending an HVS for screening for GBS is unwarranted in this case.
  • Intrauterine devices should NOT be routinely sent to the laboratory after their removal. IUCDs are only investigated if there are clinical indications of PID or other inflammatory conditions.

STI screening (Chlamydia, Gonorrhoea, Trichomoniasis) - send Aptima sample

High Vaginal Swab for culture (NB, investigation does NOT include STI screening)

Specimen types you should send:

  • High vaginal swab (HVS). Indications for HVS are: -

    Symptoms consistent with recurrent thrush, vaginal pH < 4.5

    Abnormal discharge NOT consistent with BV or TV, vaginal pH > 4.5

    Abnormal discharge in a patient who is > 60 years old or who has dyspareunia or dysuria Group B streptococcal screening in pregnancy

How to collect the sample

  • Remove all excessive amount of secretions or discharge.
  • Obtain samples from the mucosal membrane of the vaginal vault. Use a speculum if available.

Which container does it go in?

  • HVS for culture: Liquid e-Swab (NB these are not investigated for STIs)

Transport

  • Swabs should be transported to the laboratory as soon as possible.

Other GUS tests

IUCD - If Actinomyces is suspected or shown in the endocervical smear, separate prolonged culture techniques are required and the clinical information must be clearly stated on the request form.

Pregnancy - Group B Strep may cause neonatal invasive disease. Send an HVS for screening. Women known to be carriers of group B strep at onset of labour are offered parenteral prophylaxis.

Children- Vulval and penile swabs from children are investigated for skin/soft tissue pathogens including Staph aureus and Group A haemolytic streptococcus.

Suspected sexual abuse – refer urgently to Consultant Paediatrician. Documented procedure for clinical examination and testing, and chain of custody documentation, is mandatory.

Culture for N gonorrhoeae - only when GC treatment is planned

Referral to LSH is recommended for investigation/treatment of gonorrhoea

(This will permit rapid laboratory processing and will facilitate contact tracing and expert support)


    Page Reviewed: 13/06/17 | Updated by: Kevin Roberts