Gut Microbiota Alternation in Disease Progression of Neurosyphilis

BACKGROUND: The gut microbiota plays an important role in the development of neurological disorders such as Parkinson’s disease and Alzheimer’s disease. However, studies on the gut microbiota of patients with neurosyphilis (NS) were rarely reported. METHODS: In this study, we collected fecal samples from 62 syphilis patients, including 39 with NS and 23 with non-NS. Among the NS patients, 18 were general paresis (GP). The white blood cell counts, protein concentrations, and Venereal Disease Research Laboratory test positive rates of cerebrospinal fluid from patients in NS or GP group were significantly higher than those from patients in non-NS group. 16S ribosomal RNA sequencing results revealed that the alpha and beta diversities of the gut microbiota were similar between NS and non-NS patients or GP and non-NS patients. RESULTS: Linear discriminant analysis with effect size (LEfSe) analysis showed that some taxa, such as Coprobacter, were increased in both NS group and GP group, compared with non-NS group. Besides, the clade of Akkermansia was also overrepresented in GP Patients. Meanwhile, some taxa such as Clostridia_UCG-014 and SC-I-84 were underrepresented in NS patients. The abundances of class Bacilli and genus Alloprevotella were decreased in GP patients. Among them, the abundances of some taxa such as Coprobacter and Akkermansia have been reported to be associated with other neuropsychiatric disorders. CONCLUSION: Our findings suggest that the alternation of the gut microbiota in NS patients may contribute to the course of NS, which will deepen our understanding of NS.