Screening for prevalence and abundance of Capnocytophaga spp by analyzing NGS data. A scoping review.

BACKGROUND Capnocytophaga spp. are commensal bacteria of the oral cavity and constitute a genus of the core microbiome. OBJECTIVE This genus is responsible for many local and systemic conditions in both the immunocompetent and immunocompromised, but its beneficial or deleterious role in the microbiota has been little explored. DESIGN Online databases were used to identify papers published from 1999 to 2019 based on next-generation sequencing (NGS) data to study comparative trials. Work using other identification methods, case reports, reviews, and non-comparative clinical trials were excluded. RESULTS AND CONCLUSION We selected 42 papers from among 668 publications. They showed a link between the abundance of Capnocytophaga spp. in the oral microbiota and various local pathologies (higher for gingivitis and halitosis; lower in active smokers, etc.) or systemic diseases (higher for cancer and carcinomas, IgA nephropathy, etc.). After discussing the limits inherent to the NGS techniques, we present several technical and biological hypotheses to explain the diversity of results observed between studies, as well as the links between the higher or lower abundance of Capnocytophaga spp and the appearance of local or systemic conditions and diseases.