Interpretation
Mixed vaginitis refers to a vaginitis that combines two or more pathogens that cause AV, BV, VVC, and TV(2). The interaction between fungi and bacteria can mutually promote the colonization and virulence of pathogens (28). C.albicans (VVC pathogen) adhesion proteins, hyphal wall proteins, and transcriptional regulators play a crucial role in the interaction between C.albicans andStaphylococcus (AV pathogen)(29, 30). The mouse model of mixed infection of GBS and C.albicans confirmed that GBS could also promote the adhesion and colonization of C.albicans , while reducing the cellular immune response and host immune clearance rate of helper T cell 17 (Th17), ensuring the persistently chronic infection of the two(31). C.albicans can combine with a variety of streptococci and staphylococci(AV pathogen) to help them adhere and form biofilms(30). The dual-species biofilm formed can provide nutrients for pathogens to reproduce, and protect microorganisms from being eliminated by antimicrobial agents, further maintaining the pathogenic ability of pathogens(30, 32-37).The interaction between aerobic and anaerobic bacteria can promote biofilm formation and participate in the pathogenic process. In vitro experiments have confirmed thatEscherichia coli and Enterococcus faecalis (AV pathogens) coexist and interact with Gardnerella vaginalis (BV pathogen) to participate in the formation of BV biofilms (38). Therefore, the interaction between fungi and bacteria and between bacteria and bacteria is very important for the pathogenic processes of mixed vaginitis. Immunity is reduced during pregnancy. The host’s ability to suppress pathogens is reduced. Mixed vaginitis during pregnancy may be more serious and complicated. The existence of multi-species biofilms in the vagina of pregnant women is related to the occurrence of adverse outcomes. This may come from the upward spread of biofilms, but the mechanism still needs further research.