For a study, researchers assessed whether transperineal (TP) prostate biopsy was linked to a lower level of pathogen introduction into the prostate compared to transrectal (TR) biopsy in order to understand the mechanistic basis for fewer infectious consequences in TP prostate biopsy.

Rectal and perineal skin swabs as well as two additional biopsy cores were taken from males who were scheduled for prostate biopsy for routine clinical indications. Next-generation sequencing, routine laboratory culture, and DNA extraction were all performed on the specimens. In prostate core biopsy tissue from patients who underwent TP vs. TR biopsy, microbial quantity and composition were assessed and compared.

The research included 23 men in total. In comparison to the TR group, biopsy core tissue from the TP group had fewer known pathogens (36.3 vs 104.2 normalized counts of pathogens/sample, P=.018) and had less known microbial diversity (15.0 vs 25.8 phylogenetic clades/sample, P=.0004). The perineal rather than the rectal source was more responsible for the TP group tissue core flora (P=.047). About 45% of the TR group’s cores contained viable Escherichia coli, although none of the TP group’s did (P=.014).

The risk of viable E. coli in biopsy tissue from patients who receive TP biopsy was significantly lower than that of patients who have TR biopsy. The findings provided a justification for the broad use of TP biopsy and a potential rationale for the lower infectious risk associated with TP biopsy compared to TR biopsy.