Cervicovaginal Fungi and Bacteria Associated With Cervical Intraepithelial Neoplasia and High-Risk Human Papillomavirus Infections in a Hispanic PopulationOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study examined whether cervicovaginal bacteria and fungi shift with HPV infection and cervical precancer in a high-risk Hispanic population. DNA from cervix, introitus, and anal swabs was sequenced for the bacterial 16S rRNA V4 region and the fungal ITS-2 region using Illumina technology. HPV was genotyped with the SPF10-LiPA25 assay. Diversity, taxa, and co-occurrence were compared across HPV risk categories and lesion grades.
Who was studied?
The cohort was 62 reproductive-age Puerto Rican women, aged 21 to 50, attending high-risk gynecology and colposcopy clinics in San Juan. Women with recent antibiotics, active infections, or candidiasis were excluded. Microbiota were analyzed in 58 of the 62 patients after quality filtering. HPV prevalence was 84 percent, with about 44 percent carrying high-risk types and many co-infected with up to nine HPV types.
What were the most important findings?
Bacterial diversity tracked lesion severity, not HPV risk. Shannon diversity was significantly higher in CIN3 than CIN1 lesions in both vaginal and cervical samples, at p of 0.033 and 0.031. No significant bacterial biomarkers emerged for HPV infection itself. Lactobacillus was ubiquitous, present in over 83 percent of samples. Fungal diversity instead tracked HPV risk. Cervical fungal Shannon diversity was significantly higher in high-risk HPV samples at p of 0.05. Sporidiobolaceae dominated most samples and was enriched in ASCUS and low-risk HPV, while Malassezia-type yeasts associated with high-risk HPV.
What are the greatest implications of this study?
The results suggest cervicovaginal bacteria and fungi occupy distinct roles, with bacterial diversity linked to lesion progression and fungal diversity linked to high-risk HPV. Mapping this ecosystem may aid future understanding of cervical neoplasia. The authors note the modest sample size limits detection of true biomarkers and preclude firm causal conclusions. The associations are observational and specific to a Hispanic population.