Association between systemic lupus erythematosus and disruption of gut microbiota: a meta-analysis.

Objective: Recent studies reported that SLE is characterised by altered interactions between the microbiome and immune system. We performed a meta-analysis of publications on this topic.

Methods: Case-control studies that compared patients with SLE and healthy controls (HCs) and determined the diversity of the gut microbiota and the abundance of different microbes were examined. Stata/MP V.16 was used for the meta-analysis. A Bonferroni correction for multiple tests was used to reduce the likelihood of false-positive results.

Results: We included 11 case-control studies that examined 373 patients with SLE and 1288 HCs. These studies were performed in five countries and nine cities. Compared with HCs, patients with SLE had gut microbiota with lower Shannon-Wiener diversity index (weighted mean difference=-0.22, 95% CI -0.32 to -0.13, p<0.001) and lower Chao1 richness (standardised mean difference (SMD)=-0.62, 95% CI -1.04 to -0.21, p=0.003). Patients with SLE had lower abundance of Ruminococcaceae (SMD = -0.49, 95% CI -0.84 to -0.15,p=0.005), but greater abundance of Enterobacteriaceae (SMD=0.45, 95% CI 0.01 to 0.89, p=0.045) and Enterococcaceae (SMD=0.53, 95% CI 0.05 to 1.01, p=0.03). However, only the results for Ruminococcaceae passed the Bonferroni correction (p=0.0071). The two groups had no significant differences in Lachnospiraceae and Bacteroides (both p>0.05). Patients with SLE who used high doses of glucocorticoids had altered gut microbiota based on the Chao1 species diversity estimator, and hydroxychloroquine use appeared to reduce the abundance of Enterobacteriaceae.

Conclusions: Patients with SLE have imbalanced gut microbiota, with a decrease in beneficial bacteria and an increase in harmful bacteria. Drugs used to treat SLE may also alter the gut microbiota of these patients.