Spontaneous Closure of a Post-biopsy Rectoprostatic Fistula via Dual Urinary Diversion: A Case Report and Review of Conservative Management.

Rectoprostatic fistula (RPF) is an exceedingly rare but severe complication of transrectal ultrasound (TRUS)-guided prostate biopsy. It typically represents the terminal stage of a post-biopsy prostatic abscess that perforates the Denonvilliers' fascia. We present a case of RPF successfully managed through a conservative "urinary-first" strategy. A 70-year-old male with type 2 diabetes mellitus and a glycated hemoglobin level of 8% presented eight weeks following a TRUS-guided biopsy with pathognomonic symptoms of fecaluria, pneumaturia, and urine passage per rectum. The patient had a history of recurrent Enterococcus faecalis urinary tract infections post-procedure. Digital rectal examination and multi-modal imaging (voiding cystourethrography, cystoscopy, and MRI) confirmed a Rivera class II rectourethral communication. Initial management with a transurethral Foley catheter was complicated by recurrent obstructions. A transition to a "dual-drainage" strategy, utilizing both a urethral catheter and a suprapubic tube (SPT), was implemented to ensure superior anatomical rest. After four weeks of diversion, follow-up cystoscopy and sigmoidoscopy confirmed complete spontaneous closure of the fistula. In high-risk patients, particularly those with diabetes, persistent post-biopsy symptoms should prompt immediate investigation for a prostatic abscess to prevent fistulization. This case highlights that a conservative approach using dual urinary drainage (SPT and Foley) can effectively facilitate secondary intention healing, potentially sparing patients from the morbidity of major reconstructive surgery.