Abstract
Recurrent vulvovaginal candidiasis (RVVC) is a multifactorial condition in which vaginal microbiota dysbiosis plays a key role. This study aimed to characterize the vaginal microbiome of patients with RVVC using metagenomic sequencing. Vaginal scraping samples were collected from 34 women aged 20-47 years and classified into three groups: (1) 14 women with RVVC who had experienced 3-7 episodes of VVC in the previous year; (2) 9 women with severe RVVC, defined as ≥8 episodes in the last year; and (3) 11 healthy women as controls. The results revealed an increased relative abundance of bacteria associated with bacterial vaginosis-including Gardnerella vaginalis, G. swidsinskii, and Prevotella bivia-as well as higher levels of Lactobacillus iners in both RVVC groups. In contrast, healthy women showed a greater abundance of L. crispatus and L. gasseri. Diversity analyses indicated lower α-diversity in the healthy group compared to RVVC patients. Metabolic potential profiling showed a differential increase in sequences related to the phosphotransferase system, fructose/mannose metabolism, pentose phosphate pathway, and cysteine/methionine and purine metabolism in RVVC groups relative to controls; no significant differences were observed between RVVC groups, indicating that microbial profiles alone do not correlate with the degree of disease severity. These findings provide relevant insights into the taxonomic and functional characteristics of the vaginal microbiome in women with RVVC and may support the development of targeted therapeutic strategies.