In our study “Characterization of Changes in Penile Microbiome Following Pediatric Circumcision”, we aimed to investigate the changes in the microbiome and mycobiome of the penis that occurs following circumcision, with the goal of understanding any potential contributions to later pathologies such as penile cancer and lichen sclerosis.1 It is known that uncircumcised men are at higher risk for these conditions, but the specific mechanisms behind this increased risk are not fully understood. Studying the microbiome of the penis after circumcision is challenging because a variety of factors, such as infections and treatments, can influence the microbiome. Many men who undergo circumcision may have had previous infections or used ointments or antibiotics, which can alter the microbiome and make it difficult to reflect the true microbiome accurately. Despite these challenges, understanding the changes in the microbiome after circumcision may provide valuable insights into the potential contributions of the microbiome to the development of penile cancer and lichen sclerosis. We also aimed to understand how the host's mycobiome interacts with changes in the microbial composition that occur after circumcision.
We collected and analyzed 11 paired samples from the periurethral area to create profiles of the microbiome and mycobiome both before and after circumcision. One of the key findings of our study was that there was a significant decrease in the abundance of specific bacterial groups after circumcision. Particularly, we observed a considerable decrease in Clostridiales, Bacteroidales, Campylobacterales, and Enterobacteriales. Additionally, we found that certain genera, such as Prevotella and Sulfurimonas, were more prevalent in samples taken before circumcision than those taken after the procedure. Our functional analysis also identified the presence of sulfate-reducing bacteria and high levels of thiosulfate reductase and polysulfate reductase in uncircumcised boys.
We hypothesize that hydrogen sulfide production, which has been linked to inflammation from previous studies, and these sulfur-reducing bacteria in the uncircumcised state may contribute to the inflammatory and possibly oncogenic process. Unlike bacteria components, while we did highlight a decrease in the abundance of certain fungi, such as Saccharomycetales and Pleosporales post circumcision, surprisingly the fungi did not exhibit large fluctuations.
The information gained from our study sets the foundation to understand the impact of the penile microbiome and mycobiome in disease pathogenesis and may inform clinical decision-making about this procedure.
Written by: llaha Isali, MD,1 Kirtishri Misha, MD,2 & Laura Bukavina, MD, MPH3
- Case Western Reserve University, Cleveland, OH
- University Hospitals of Cleveland, Cleveland, OH
- Fox Chase Cancer Center, Philadelphia, PA
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