To synthesize evidence on oral and gut microbiome alterations in systemic lupus erythematosus (SLE) and primary Sjögren’s syndrome (pSS), focusing on opposing abundance patterns across anatomical sites.
Approach:
Data Synthesis: Microbial alterations were harmonized using NCBI taxonomy and synthesized descriptively, focusing on patterns without conducting meta-analysis.
Key Findings:
Thirty-three studies comprising 1,385 patients and 2,131 healthy controls were included.
Intestinal Shannon and Simpson α-diversity were frequently reduced, while oral diversity was preserved or increased.
Recurrent opposing abundance patterns were observed for specific taxa, notably involving Streptococcus and Actinomycetota in SLE and Pseudomonadota in pSS.
Certain taxa, including Veillonella and Veillonellaceae, showed parallel enrichment across both oral and gut sites.
Interpretation:
Limitations:
Causal inference is limited due to the predominance of cross-sectional studies.
Data derived primarily from relative abundances may not reflect absolute microbial counts.
