Does Formalin Disinfection Reduce Bacterial Colonization of Biopsy Needle? A Prospective Study

To investigate the efficacy of formalin disinfection of the needle tip in transrectal prostate biopsy (TRB) procedure to reduce infectious complications. The primary aim is to assess the impact of formalin on bacterial contamination of biopsy needle tips and its association with post-biopsy infective events.

We have employed a bacterial culture-based observational cohort design in this study. Two groups, formalin disinfection and non-formalin group, both underwent systematic 12-core TRB. In the formalin group, the biopsy needle tip was immersed in 10% formalin solution after each core, while in the non-formalin group, no formalin solution immersion was used. The primary outcomes include bacterial growth on biopsy needle tips and post-biopsy infective events.

Formalin disinfection significantly reduced bacterial growth on needle tips (P <.001). The formalin group had no post-biopsy infections or sepsis, while the non-formalin group experienced a 7.5% infective event rate after TRB.

Formalin disinfection of biopsy needle tip significantly reduces bacterial growth on biopsy needle and urinary tract infectious complications developed secondary to TRB. Further multicenter randomized controlled studies with larger cohorts are warranted to validate and establish formalin disinfection as a routine practice in TRB procedures.