Table 1

Case definitions used for diagnosis of neurosyphilis and tertiary syphilis (Adapted from Ref. 17)

Syphilis stageDefinition
Tertiary syphilisReactive treponemal serology together with characteristic late abnormalities of the cardiovascular system, bone, skin or other structures, in the absence of other known causes of these abnormalities and no clinical or laboratory evidence of neurosyphilis
Early neurosyphilis
(<1 year after infection)
Asymptomatic
Laboratory confirmation of primary, second or early latent syphilis and
(i) reactive CSF-VDRL in non-bloody CSF
AND/OR
(ii) elevated CSF leucocytes (>5/10E6/L) and/or elevated CSF protein (>0.45 g/L) in the absence of other known causes
AND
NO signs or symptoms of neurosyphilis
Early neurosyphilis
(<1 year after infection)
Symptomatic
Laboratory confirmation of primary, second or early latent syphilis and
(i) reactive CSF-VDRL in non-bloody CSF
AND/OR
(ii) elevated CSF leucocytes (>5/10E6/L) and/or elevated CSF protein (>0.45 g/L) in the absence of other known causes
AND clinical signs or symptoms of neurosyphilis*
Late neurosyphilis
(>1 year after infection)
Asymptomatic
Reactive treponemal serology (not staged as primary, secondary or early latent syphilis) and
(i) reactive CSF-VDRL in non-bloody CSF
AND/OR
(ii) elevated CSF leucocytes (>5/10E6/L) and/or elevated CSF protein (>0.45 g/L) in the absence of other known causes
AND
NO clinical signs or symptoms of neurosyphilis
Late neurosyphilis
(>1 year after infection)
Symptomatic
Reactive treponemal serology (not staged as primary, secondary or early latent syphilis) and
(iii) reactive CSF-VDRL in non-bloody CSF
AND/OR
(iv) elevated CSF leucocytes (>5/10E6/L) and/or elevated CSF protein (>0.45 g/L) in the absence of other known causes
AND clinical signs or symptoms of neurosyphilis*
  • *If ocular or otic signs or symptoms present with a normal CSF examination, patient was classified as symptomatic neurosyphilis (early or late).

  • CSF, cerebrospinal fluid; LLS, late latent syphilis; STI, sexually transmitted infection; VDRL, Venereal Disease Research Laboratory.