Ling Z. et al. record a more pronounced vaginal dysbiosis, in contrast to that found in the examination of fecal matter in the case of patients with SLE, characterized by a different predominance of frequently encountered species, but also by an intense association between the vaginal microbiome of the patients and the immunological picture of the disease (negative correlation between the C4 fraction of complement and Bacteroides, Escherichia and Shigella) [55]. This evidence concerns the gene C4A and systemic lupus erythematosus.