How should I manage an elderly male patient with a chronic perineal wound that repeatedly forms abscesses and reopens 25 years after radical prostatectomy?

Management of Chronic Perineal Wound with Recurrent Abscesses 25 Years Post-Radical Prostatectomy

Immediate Surgical Management

This chronic perineal wound requires urgent surgical debridement with complete removal of all necrotic tissue, followed by negative pressure wound therapy (NPWT), as inadequate source control is the primary driver of recurrence in chronic perineal wounds. 1

Surgical Approach

• Perform examination under anesthesia (EUA) to fully assess the wound extent, identify any occult fistulous connections to the rectum or urethra, and evaluate for undrained fluid collections that cannot be reliably assessed at bedside due to pain and chronic tissue distortion 1

• Execute aggressive debridement of all necrotic, infected, and non-viable tissue during the initial procedure, continuing debridement into healthy-appearing tissue to halt progression 2

• Plan serial surgical revisions every 12-24 hours until the wound bed is completely free of necrotic tissue, as this is the cornerstone of managing chronic infected perineal wounds 2

• Thoroughly break up any loculations within the wound cavity, as loculated collections are associated with recurrence rates up to 44% 1

Timing of Intervention

• Emergency drainage within hours is mandatory if the patient exhibits sepsis, severe sepsis, immunosuppression, diabetes, or extensive surrounding cellulitis 1

• In the absence of these high-risk features, surgical debridement should still occur within 24 hours of presentation 1

Evaluation for Fistulous Disease

Given the 25-year history and recurrent nature, there is high likelihood of an underlying fistula to the rectum or urethra that perpetuates infection.

• During EUA, carefully inspect for fistulous openings to the rectum or urethra, as approximately one-third of chronic perineal abscesses harbor occult fistulas that markedly increase recurrence risk 1

• Do NOT probe aggressively for fistulas if none are immediately apparent, as probing can cause iatrogenic injury without reducing recurrence 1

• If a fistula involving the rectum is identified, consider diverting colostomy to minimize bacterial contamination of the perineal wound, as this decreases sepsis by reducing bacterial load and helps control infection 2

• Alternatively, use a temporary fecal management system (rectal diversion tube) in combination with NPWT as an effective alternative to colostomy for fecal diversion 2

• If urethral involvement or periurethral abscess is present, place a suprapubic catheter for urinary diversion rather than relying on transurethral catheterization 2

Post-Debridement Wound Management

After complete debridement, apply negative pressure wound therapy (NPWT) to the perineal wound, as this modality has multiple beneficial effects on wound healing in chronic infected wounds.

• NPWT increases local blood supply, encourages migration of inflammatory cells, removes exudate and bacteria, and promotes granulation tissue formation 2

• Continue NPWT until the wound bed demonstrates healthy granulation tissue without signs of infection 2

• Do NOT pack the wound with traditional gauze, as current evidence suggests packing increases cost and pain without improving healing 1

Antibiotic Therapy

Administer empiric broad-spectrum intravenous antibiotics covering gram-positive (including MRSA), gram-negative, and anaerobic organisms, as chronic perineal wounds are polymicrobial.

• Use piperacillin-tazobactam 3.375g IV every 6 hours PLUS vancomycin 15-20 mg/kg IV every 8-12 hours to provide comprehensive coverage including MRSA, which is present in 19-35% of perirectal abscesses but frequently underrecognized 1

• Obtain cultures of infected fluid and tissue during initial debridement to tailor antibiotic therapy based on sensitivities 2, 1

• Continue antibiotics for 7-10 days total following operative drainage 1

• Antibiotics are mandatory in this case given the chronic nature, recurrent abscesses, and high likelihood of incomplete source control 1

Imaging and Diagnostic Workup

• Obtain pelvic MRI with contrast to evaluate for deep abscess collections, fistulous tracts, and extent of tissue involvement, as MRI has 76-100% accuracy for detecting fistulous disease 1

• Do NOT delay surgical drainage while awaiting imaging if the clinical diagnosis is clear 1

• Screen for undiagnosed or poorly controlled diabetes mellitus by checking fasting glucose, hemoglobin A1c, and urine ketones, as diabetes impairs wound healing and increases infection risk 1

• Consider endoscopic evaluation of the rectum if rectal fistula is suspected, as proctitis is a predictive factor for persistent non-healing fistula tracts 1

Definitive Reconstruction

After achieving infection control and a clean granulating wound bed, consult plastic surgery for consideration of tissue transfer techniques.

• Omental pedicle flaps, vertical rectus abdominis myocutaneous flaps, or gracilis muscle flaps can reconstruct large perineal defects and decrease complications in chronic perineal wounds 3

• Tissue transfer is particularly important in this case given the 25-year chronicity and likely radiation changes to surrounding tissue (if the patient received adjuvant radiation therapy post-prostatectomy) 3

Critical Pitfalls to Avoid

• Failing to achieve complete source control with inadequate debridement is the leading cause of recurrence 1

• Attempting to manage with antibiotics alone without surgical drainage will result in treatment failure 1

• Missing an underlying fistula to the rectum or urethra perpetuates the cycle of infection and abscess formation 1

• Inadequate MRSA coverage in recurrent cases leads to treatment failure, as this organism is significantly underrecognized in perineal infections 1

• Performing overly timid or small incisions during drainage is a leading cause of recurrence 1