Cerebrospinal fluid CXCL13 concentration for diagnosis and monitoring of neurosyphilis in people with HIV

Abstract

Objectives: The study aimed to assess and compare CSF-CXCL13 levels in People Living with HIV (PLWH) with suspected neurosyphilis (NS), those with syphilis but without NS, and patients without treponema infection. Additionally, it aimed to evaluate changes in CSF-CXCL13 concentrations before and after antibiotic treatment. Design: This was a prospective cohort study involving 93 PLWH suspected of NS. All participants underwent lumbar puncture, with CSF-CXCL13 levels measured at baseline and during follow-up in patients diagnosed with NS. Methods: CSF-CXCL13 levels were quantified using ELISA. The Mann-Whitney U test was used to analyze differences between groups, while the Wilcoxon test assessed withinsubject changes. ROC curve analysis determined the diagnostic efficacy of CSFCXCL13 for NS. Results: Significantly higher CSF-CXCL13 levels were observed in patients with NS compared to those with syphilis without NS and non-syphilis patients. Post-treatment, a decline in CSF-CXCL13 levels was noted in all NS cases. A CSF-CXCL13 threshold exceeding 60.0 pg/mL, in conjunction with reactive CSF-FTA-ABS, yielded a sensitivity of 88.9% and a specificity of 97.6% for NS diagnosis. Conclusions: CSF-CXCL13 emerges as a valuable adjunctive biomarker for detecting NS in PLWH, especially in cases with non-reactive CSF-VDRL. Monitoring CSF-CXCL13 levels also appears effective in evaluating therapeutic response in PLWH undergoing NS treatment.