CXCL13 as a cerebrospinal fluid marker for neurosyphilis in HIV-infected patients with syphilis

Sex Transm Dis. 2010 May;37(5):283-7. doi: 10.1097/OLQ.0b013e3181d877a1.


Background: Asymptomatic neurosyphilis is more difficult to diagnose in human immunodeficiency virus (HIV)-infected patients because HIV itself can cause cerebrospinal fluid (CSF) pleocytosis. The proportion of CSF lymphocytes that are B cells is elevated in neurosyphilis, suggesting that the CSF concentration of the B cell chemoattractant, chemokine (C-X-C motif) ligand 13 (CXCL13) concentration may also be elevated.

Methods: CSF and blood were collected from 199 HIV-infected patients with syphilis and neurosyphilis. Serum and CSF CXCL13 concentrations were determined.

Results: Patients with neurosyphilis had higher CSF and serum CXCL13 concentrations compared to patients with syphilis but not neurosyphilis. The odds of having symptomatic neurosyphilis were increased by 2.23-fold for every log increase in CSF CXCL13 concentration and were independent of CSF white blood cell and plasma HIV RNA concentrations, peripheral blood CD4+ T cell count and use of antiretroviral medications. A cut-off of 10 pg/mL CSF CXCL13 had high sensitivity and a cut-off of 250 pg/mL or evidence of intrathecal synthesis of CXCL13 had high specificity for diagnosis of both symptomatic and asymptomatic neurosyphilis. CSF concentrations of CXCL13 declined after treatment for neurosyphilis.

Conclusions: CSF CXCL13 concentration may be particularly useful for diagnosis of neurosyphilis in HIV-infected patients because it is independent of CSF pleocytosis and markers of HIV disease.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Biomarkers / cerebrospinal fluid
  • Cardiolipins
  • Chemokine CXCL13 / cerebrospinal fluid*
  • Cholesterol
  • Cohort Studies
  • Female
  • HIV Infections / complications*
  • Humans
  • Male
  • Neurosyphilis / cerebrospinal fluid*
  • Neurosyphilis / diagnosis
  • Phosphatidylcholines
  • RNA, Viral
  • Reverse Transcriptase Polymerase Chain Reaction
  • Spinal Puncture
  • Syphilis / complications*
  • Syphilis / diagnosis
  • Treponema pallidum / immunology


  • Biomarkers
  • CXCL13 protein, human
  • Cardiolipins
  • Chemokine CXCL13
  • Phosphatidylcholines
  • RNA, Viral
  • VDRL antigen
  • Cholesterol