Diagnostic value of CSF CXCL8 combined with total protein for neurosyphilis: a logistic regression and ROC analysis

Neurosyphilis has resurged globally, presenting a significant public health threat, yet challenges in early diagnosis persist. This study aims to evaluate the diagnostic value of C-X-C motif chemokine ligand 1 (CXCL1), C-X-C motif chemokine ligand 5(CXCL5), and C-X-C motif chemokine ligand 8 (CXCL8) in cerebrospinal fluid (CSF) for neurosyphilis.

A total of 126 patients were included in this study, comprising 44 syphilis patients and 82 diagnosed with neurosyphilis (28 asymptomatic and 54 symptomatic). We assessed CSF chemokines, CSF parameters, and lymphocyte subpopulations. Univariate and multivariate logistic regression analyses were conducted to identify predictors of neurosyphilis. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic value of individual and combined biomarkers for this condition.

CSF CXCL1 and CSF CXCL8 levels were significantly elevated in the neurosyphilis group compared to the syphilis group (P < 0.05). Additionally, CSF white cell count (CSF WBC) and CSF total protein (CSF TP) levels were increased, while CD4 levels were decreased. Binary logistic regression analysis identified CSF CXCL8 and CSF TP as independent predictors of neurosyphilis. ROC curve analysis revealed areas under the curve (AUC) for CSF CXCL8 and CSF TP distinguishing neurosyphilis from syphilis of 0.766 and 0.830, respectively. The combined assessment of CSF CXCL8 and CSF TP further improved diagnostic accuracy, with an AUC of 0.865.

The levels of CSF CXCL1 and CSF CXCL8 are valuable for diagnosing neurosyphilis and assessing treatment efficacy. The combined detection of CSF CXCL8 and CSF TP enhances diagnostic precision.