Syphilis serology

Microbiology

Notes

 

  • A combined syphilis IgG/IgM test is performed on all samples requiring syphilis serology
  • An RPR test (equivalent to a VDRL test) is only performed on combined IgG/IgM positive samples as an indicator of activity status
  • All positive combined IgG/IgM positive samples are confirmed with a TPPA test
  • All positive samples and discrepant results are also referred to the regional reference laboratory for confirmation
  • In very early primary syphilis a false negative serology result may be obtained. If there is a high index of clinical suspicion send a repeat sample after one week

Sample requirements

Serum - paired samples not required

8.5ml of blood taken into a plain gel tube 

8.5mL BD Vacutainer tube

Required information

  • Relevant clinical details
  • Date of onset
  • Details of exposure to other suspected cases
  • Past history of syphilis
  • Treatment history

Storage/transport

Store at fridge temperature

Transport as soon as possible at ambient temperature

Turnaround time

Positive samples referred to a Regional Reference Centre

Negatives: up to 5 days 

Positives: up to 5 days for initial results and up to 8 days for confirmation


Page last reviewed: 25/11/2013