Point-of-care treponemal tests for neurosyphilis diagnosis

Sex Transm Dis. 2015 Jan;42(1):48-52. doi: 10.1097/OLQ.0000000000000222.


Background: The laboratory diagnosis of neurosyphilis rests upon identifying cerebrospinal fluid (CSF) abnormalities, including CSF-Venereal Disease Research Laboratory (VDRL) reactivity. The CSF-VDRL may not be available in the parts of the world where neurosyphilis is most common. Treponemal immunochromatographic strip tests (ICSTs) have been developed as point-of-care tests on blood for syphilis diagnosis in resource-limited settings.

Methods: We optimized 3 commercial ICSTs for performance on CSF and tested CSF samples from 217 patients with syphilis. The Syphicheck-WB test (Qualpro Diagnostics, Goa, India; "Syphicheck") was chosen for further study based on agreement with CSF-VDRL test results. We determined CSF-Syphicheck titers for 152 samples. We modified the CSF-Syphicheck for point-of-care testing in a US sexually transmitted diseases clinic and compared results on 102 paired centrifuged and uncentrifuged CSF samples obtained in the laboratory to the results obtained at point of care; results of samples diluted 1:4 were compared in a subset.

Results: The diagnostic sensitivity of a reactive CSF-Syphicheck (62%-64%) and the diagnostic specificity of a CSF-Syphicheck titer at or above 1:4 (79%-81%) were equivalent to the CSF-VDRL (54%-69% sensitivity, 73%-75% specificity) for laboratory and clinical neurosyphilis diagnoses. The CSF-Syphicheck normalized after neurosyphilis therapy similarly to the CSF-VDRL. The modified CSF-Syphicheck performed well at the point of care, albeit with better performance on cell-free compared with uncentrifuged CSF.

Conclusions: Cerebrospinal fluid treponemal ICSTs hold promise for point-of-care neurosyphilis diagnosis in regions where the CSF-VDRL is not available. Further study should address the performance of CSF ICSTs in resource-limited settings.

Publication types

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

MeSH terms

  • Chromatography, Affinity
  • Clinical Laboratory Techniques
  • Female
  • Humans
  • Male
  • Neurosyphilis / blood
  • Neurosyphilis / cerebrospinal fluid*
  • Neurosyphilis / diagnosis*
  • Point-of-Care Systems*
  • Sensitivity and Specificity
  • Syphilis Serodiagnosis / methods*
  • Treponema pallidum / isolation & purification*