Insights Into Treatment Alternatives for Neurosyphilis: Systematic Literature Review and Meta-Analysis

We conducted a systematic literature review and meta-analysis to assess the efficacy of alternative treatments for neurosyphilis. We searched MEDLINE, Cumulative Index to Nursing and Allied Health Literature, Embase, Cochrane, Scopus, and Web of Science from database inception to September 2023, for studies in neurosyphilis that compared penicillin monotherapy with other treatments. We focused on the impact of these therapies on treatment response, but also assessed data regarding reinfection and adverse drug events. Random-effect models were used to obtain pooled mean differences. Of 3415 screened studies, 6 met the inclusion criteria for the systematic literature review. Three studies provided quantitative data that allowed for inclusion in the meta-analysis. Our analysis revealed that the efficacy of intravenous (IV) ceftriaxone 2 g daily for 10 days (51 patients) did not appear statistically different compared with IV penicillin G 18 to 24 million units daily for 10 days (185 patients) for neurosyphilis (pooled odds ratio, 2.85; 95% confidence interval, 0.41-19.56; I 2 = 49%). No statistical difference between ceftriaxone and penicillin was identified in people living with human immunodeficiency virus (HIV) (pooled odds ratio, 4.51; 95% confidence interval, 0.50-40.49; I 2 = 34%). We concluded that alternative therapy with IV ceftriaxone appears similar to penicillin, potentially expanding treatment options for neurosyphilis. Other treatment options including doxycycline warrant further study.