Scanning electron and confocal scanning laser microscopy imaging of the ultrastructure and viability of vaginal Candida albicans and non- albicans species adhered to an intrauterine contraceptive device.

Although bacterial biofilms have been studied in detail, adhesion of Candida albicans and non-albicans species to an intrauterine contraceptive device (IUD) is not clear. The objective of this study was to evaluate aspects of imaging of the ultrastructure and viability of vaginal yeasts adhered to different parts of an IUD, through scanning electron microscopy (SEM) and confocal scanning laser microscopy (CSLM). We studied yeasts isolated from different patients with vulvovaginal candidiasis: C. albicans, C. glabrata, C. guillermondii, C. parapsilosis, C. tropicalis, and Saccharomyces cerevisiae. A suspension of the each yeast was prepared and incubated with IUD parts (tail, without copper, and copper-covered). SEM and CSLM showed that all the vaginal yeasts adhered to all the parts of the IUD and demonstrated viability, including 30 days after contact for C. albicans. Possibly irregularities of IUD surface contribute to the adherence process. Although all of the IUD parts contribute to retention of yeasts in the genital tract, high concentration of yeast cells on the tail may indicate the importance of this segment in maintaining the colonization by yeast cells because the tail forms a bridge between the external environment, the vagina that is colonized by yeast cells, and the upper genital tract where there is no colonization.