Management of Recurrent Perianal Abscess with Fistula
Direct Answer
Examination under general anesthesia with immediate drainage (Option D) is the most appropriate management step for this patient with a fluctuant perianal abscess and underlying fistula. 1, 2
Rationale and Clinical Approach
Why Immediate Surgical Drainage is Mandatory
Examination under anesthesia with drainage should not be postponed even if pelvic imaging is unavailable when a perianal abscess is clinically suspected, as the presence of fluctuation indicates a collection requiring urgent surgical drainage. 1, 2
The timing should be within 24 hours for patients without sepsis, emergent cellulitis, immunosuppression, or diabetes—this patient's recurrent presentations suggest adequate immune function but the fluctuant mass demands prompt intervention. 2
The history of recurrent presentations with spontaneous drainage strongly indicates underlying fistula-in-ano, which occurs in approximately one-third of perianal abscess cases and requires surgical assessment rather than conservative management. 1, 2, 3
Why Other Options Are Inappropriate
CT pelvis (Option A) is incorrect because imaging should not delay definitive surgical drainage when clinical examination clearly demonstrates a fluctuant abscess—guidelines explicitly state that EUA with drainage should proceed even without imaging. 1, 2
Oral antibiotics with outpatient follow-up (Option B) is incorrect because antibiotics alone cannot adequately drain a fluctuant collection and have no influence on fistula formation or recurrent abscess development after perianal abscess. 2, 4
Bedside needle aspiration (Option C) is incorrect because perianal abscesses require adequate surgical drainage with proper exploration under anesthesia, not simple aspiration which provides inadequate drainage and risks incomplete treatment. 2, 5
Critical Management Principles During EUA
Do not actively probe for the fistula during acute abscess drainage to avoid creating iatrogenic tracts and complicating future management. 2, 6
If an obvious fistula is identified without probing, place a loose draining seton rather than laying it open using low-profile, soft material to control sepsis while preserving sphincter function. 2
Never attempt fistulotomy during acute abscess drainage to minimize tissue disruption and preserve anal function—definitive fistula management requires subsequent treatment planning after acute sepsis resolves. 2, 3
Essential Additional Workup
Check serum glucose, hemoglobin A1c, and urine ketones to identify undetected diabetes mellitus, which significantly impacts healing and recurrence risk. 1, 6
Exclude underlying Crohn's disease in every patient with recurrent anorectal abscess by obtaining focused history for inflammatory bowel disease symptoms (diarrhea, weight loss, abdominal pain), as Crohn's disease occurs in approximately one-third of patients and markedly reduces surgical success rates. 1, 2, 6
Perform endoscopic evaluation of the rectum after the acute phase to determine the most appropriate long-term management strategy for the underlying fistula. 1, 2
Post-Operative Management
Routine imaging after drainage is not required unless there is recurrence, suspected inflammatory bowel disease, or evidence of non-healing wound. 2, 6
Antibiotics are not routinely needed after adequate surgical drainage unless sepsis or significant cellulitis is present, as antibiotic therapy has no influence on anal fistula or recurrent perianal abscess formation. 2, 4
Counsel the patient that definitive fistula management will require subsequent treatment planning after acute sepsis resolves, potentially including sphincter-sparing procedures to balance complete fistula treatment with continence preservation. 2, 6, 3