Metabolic Disorders in Patients with Central Nervous System Infections: Associations with Neurosyphilis

Introduction: Recently, neurosyphilis was found to be associated with diabetes mellitus (DM). Whether the association was specific to neurosyphilis among central nervous system (CNS) infections, and whether neurosyphilis is associated with other prevalent metabolic disorders deserves further study. Methods: An in-depth cross-sectional study was conducted with 74 neurosyphilis patients and 74 sex- and age-matched patients with other CNS infections. DM-, hypertension-, and dyslipidemia-related factors were compared between patients with neurosyphilis and those with other CNS infections. Results: The prevalence rates of hypertension and hyperlipidemia in neurosyphilis patients were 45.9 and 21.4%, respectively, which were higher than those in patients with other CNS infections (45.9 vs. 28.4%, p = 0.027; 21.4 vs. 8.3%, p = 0.028). In addition, neurosyphilis patients had significantly higher systolic blood pressure (BP; median 139 mm Hg; interquartile range [IQR] 121-151 mm Hg), -diastolic BP (median 83 mm Hg; IQR 76-89 mm Hg), total cholesterol (median 4.86 mmol/L; IQR 3.80-5.51 mmol/L), low-density lipoprotein (median 3.39 mmol/L; IQR 2.52-3.95 mmol/L), and apolipoprotein A1 (apoA1; median 1.31 g/L; IQR 1.06-1.52 g/L) levels and lower apoB/A1 ratios (median 0.67; IQR 0.49-0.99) than patients with other CNS infections (p< 0.05). There were no differences in the DM-related factors between patients with neurosyphilis and those with other CNS infections (p> 0.05). Conclusion: Potential association between neurosyphilis and metabolic disorders was found among CNS infections. The results could have important implications for clinical practice, alerting more clinicians to this issue.