Formalin disinfection of prostate biopsy needles may reduce post-biopsy infectious complications

Abstract

Background: We sought to determine whether formalin disinfection of prostate biopsy needles between cores reduces post-biopsy urinary tract infections (UTIs).

Methods: We reviewed a single-surgeon experience of transrectal prostate biopsies from 2010 to 2014. Biopsies were performed in either an operative suite, where 10% formalin was used to disinfect the needle tip between each biopsy core, or an outpatient clinic, where formalin was not used. Our primary outcome was post-biopsy UTI rates, defined as a positive urine culture within 30 days of biopsy. Infection severity was characterized by the need for admission. Patient demographics, prostate size, prior biopsies, prior UTIs, pre-biopsy antibiotics and cultures and post-biopsy cultures were analyzed. Logistic regression was used to assess predictors of post-biopsy UTIs. Statistical significance was defined as P<0.05.

Results: A total of 756 patients were included for analysis, including 253 who received formalin disinfection and 503 who did not. Of these, 32 patients (4.2%) experienced post-biopsy UTIs, with 8 requiring admission (all without formalin use). Infection rates were more than double in the group that did not receive formalin (5.2% vs 2.3%, P=0.085). More patients in the formalin group had undergone prior biopsies (73.9% vs 31.8%, P<0.001). On multivariable analysis, prior UTI (odds ratio (OR) 3.77, P=0.006) was a significant predictor for post-biopsy infection, whereas formalin disinfection trended towards a protective effect (OR 0.41, P=0.055).

Conclusion: Infectious complications following prostate biopsy may be mitigated by the use of formalin disinfection of the biopsy needle between cores.

Conflict of interest statement

CONFLICT OF INTEREST

The authors declare no conflict of interest.