NCT06152393

Value of an Intrathecal Synthesis Index of Specific Antitreponema IgG for Neurosyphilis Diagnosis

Retro-prospective Multicentric Study Aiming to Evaluate the Benefit of Measuring an Intrathecal Synthesis Index of Specific Antitreponema IgG for Patients Suspected of Neurosyphilis

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 181 (actual)
• Sponsor: University Hospital, Geneva · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

A retro-prospective case-control Swiss study was conducted to evaluate the diagnostic performance of measuring an antibody index (AI) for intrathecal synthesis of specific anti-Treponema pallidum (T. pallidum) IgG for the diagnosis of neurosyphilis.

Detailed description

The diagnosis of neurosyphilis (NS) lacks a true "gold standard" which makes the diagnosis challenging while consequences of a misdiagnosis are potentially severe. The aim of this study was to evaluate the diagnostic performance of measuring an antibody index (AI) for intrathecal synthesis of specific anti-Treponema pallidum (T. pallidum) IgG for the diagnosis of NS. CSF parameters were analysed and specific anti-T. pallidum IgG were measured simultaneously on paired cerebrospinal fluid (CSF)-serum samples collected between 2007 and 2022 from patients suspected of NS, in Switzerland. An AI was calculated to consider blood-brain barrier integrity. Two NS definitions were used: NS1 included patients with suspicion of NS presenting neurological symptoms and/or acute neuro-sensory signs and positive TPHA/TPPA serology and CSF-TPHA/TPPA≥320, and either CSF-leucocytes \>5cells/mm3 and/or CSF-protein \>0,45g/l and/or a reactive CSF-VDRL/RPR test. NS2 included patients with NS suspicion presenting acute ocular and/or otologic symptoms, and positive TPHA/TPPA serology, and a favourable response to NS treatment. Controls were patients diagnosed with any other CNS pathologies and with positive TPHA/TPPA serology.

Conditions

• Neurosyphilis

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Measure of an antibody index for intrathecal synthesis of specific anti-Treponema pallidum IgG by ELISA.	Paired CSF/serum samples from all patients were blind tested for anti-T. pallidum IgG with an ELISA containing recombinant T. pallidum proteins (Euroimmun). The AI was calculated conforming to Reiber's method (PMID 11239944) and as previously described in Alberto et al. (PMID 35138118).

Timeline

• Start date: 2019-03-01
• Primary completion: 2022-12-31
• Completion: 2022-12-31
• First posted: 2023-11-30
• Last updated: 2023-11-30

Locations

1 site across 1 country: Switzerland